summaryrefslogtreecommitdiffstats
path: root/fs/smb/client/connect.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /fs/smb/client/connect.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/smb/client/connect.c')
-rw-r--r--fs/smb/client/connect.c4835
1 files changed, 4835 insertions, 0 deletions
diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c
new file mode 100644
index 000000000..49fdc6dfd
--- /dev/null
+++ b/fs/smb/client/connect.c
@@ -0,0 +1,4835 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ *
+ * Copyright (C) International Business Machines Corp., 2002,2011
+ * Author(s): Steve French (sfrench@us.ibm.com)
+ *
+ */
+#include <linux/fs.h>
+#include <linux/net.h>
+#include <linux/string.h>
+#include <linux/sched/mm.h>
+#include <linux/sched/signal.h>
+#include <linux/list.h>
+#include <linux/wait.h>
+#include <linux/slab.h>
+#include <linux/pagemap.h>
+#include <linux/ctype.h>
+#include <linux/utsname.h>
+#include <linux/mempool.h>
+#include <linux/delay.h>
+#include <linux/completion.h>
+#include <linux/kthread.h>
+#include <linux/pagevec.h>
+#include <linux/freezer.h>
+#include <linux/namei.h>
+#include <linux/uuid.h>
+#include <linux/uaccess.h>
+#include <asm/processor.h>
+#include <linux/inet.h>
+#include <linux/module.h>
+#include <keys/user-type.h>
+#include <net/ipv6.h>
+#include <linux/parser.h>
+#include <linux/bvec.h>
+#include "cifspdu.h"
+#include "cifsglob.h"
+#include "cifsproto.h"
+#include "cifs_unicode.h"
+#include "cifs_debug.h"
+#include "cifs_fs_sb.h"
+#include "ntlmssp.h"
+#include "nterr.h"
+#include "rfc1002pdu.h"
+#include "fscache.h"
+#include "smb2proto.h"
+#include "smbdirect.h"
+#include "dns_resolve.h"
+#ifdef CONFIG_CIFS_DFS_UPCALL
+#include "dfs_cache.h"
+#endif
+#include "fs_context.h"
+#include "cifs_swn.h"
+
+extern mempool_t *cifs_req_poolp;
+extern bool disable_legacy_dialects;
+
+/* FIXME: should these be tunable? */
+#define TLINK_ERROR_EXPIRE (1 * HZ)
+#define TLINK_IDLE_EXPIRE (600 * HZ)
+
+/* Drop the connection to not overload the server */
+#define MAX_STATUS_IO_TIMEOUT 5
+
+struct mount_ctx {
+ struct cifs_sb_info *cifs_sb;
+ struct smb3_fs_context *fs_ctx;
+ unsigned int xid;
+ struct TCP_Server_Info *server;
+ struct cifs_ses *ses;
+ struct cifs_tcon *tcon;
+#ifdef CONFIG_CIFS_DFS_UPCALL
+ struct cifs_ses *root_ses;
+ uuid_t mount_id;
+ char *origin_fullpath, *leaf_fullpath;
+#endif
+};
+
+static int ip_connect(struct TCP_Server_Info *server);
+static int generic_ip_connect(struct TCP_Server_Info *server);
+static void tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink);
+static void cifs_prune_tlinks(struct work_struct *work);
+
+/*
+ * Resolve hostname and set ip addr in tcp ses. Useful for hostnames that may
+ * get their ip addresses changed at some point.
+ *
+ * This should be called with server->srv_mutex held.
+ */
+static int reconn_set_ipaddr_from_hostname(struct TCP_Server_Info *server)
+{
+ int rc;
+ int len;
+ char *unc, *ipaddr = NULL;
+ time64_t expiry, now;
+ unsigned long ttl = SMB_DNS_RESOLVE_INTERVAL_DEFAULT;
+
+ if (!server->hostname)
+ return -EINVAL;
+
+ /* if server hostname isn't populated, there's nothing to do here */
+ if (server->hostname[0] == '\0')
+ return 0;
+
+ len = strlen(server->hostname) + 3;
+
+ unc = kmalloc(len, GFP_KERNEL);
+ if (!unc) {
+ cifs_dbg(FYI, "%s: failed to create UNC path\n", __func__);
+ return -ENOMEM;
+ }
+ scnprintf(unc, len, "\\\\%s", server->hostname);
+
+ rc = dns_resolve_server_name_to_ip(unc, &ipaddr, &expiry);
+ kfree(unc);
+
+ if (rc < 0) {
+ cifs_dbg(FYI, "%s: failed to resolve server part of %s to IP: %d\n",
+ __func__, server->hostname, rc);
+ goto requeue_resolve;
+ }
+
+ spin_lock(&server->srv_lock);
+ rc = cifs_convert_address((struct sockaddr *)&server->dstaddr, ipaddr,
+ strlen(ipaddr));
+ spin_unlock(&server->srv_lock);
+ kfree(ipaddr);
+
+ /* rc == 1 means success here */
+ if (rc) {
+ now = ktime_get_real_seconds();
+ if (expiry && expiry > now)
+ /*
+ * To make sure we don't use the cached entry, retry 1s
+ * after expiry.
+ */
+ ttl = max_t(unsigned long, expiry - now, SMB_DNS_RESOLVE_INTERVAL_MIN) + 1;
+ }
+ rc = !rc ? -1 : 0;
+
+requeue_resolve:
+ cifs_dbg(FYI, "%s: next dns resolution scheduled for %lu seconds in the future\n",
+ __func__, ttl);
+ mod_delayed_work(cifsiod_wq, &server->resolve, (ttl * HZ));
+
+ return rc;
+}
+
+static void smb2_query_server_interfaces(struct work_struct *work)
+{
+ int rc;
+ struct cifs_tcon *tcon = container_of(work,
+ struct cifs_tcon,
+ query_interfaces.work);
+
+ /*
+ * query server network interfaces, in case they change
+ */
+ rc = SMB3_request_interfaces(0, tcon, false);
+ if (rc) {
+ cifs_dbg(FYI, "%s: failed to query server interfaces: %d\n",
+ __func__, rc);
+ }
+
+ queue_delayed_work(cifsiod_wq, &tcon->query_interfaces,
+ (SMB_INTERFACE_POLL_INTERVAL * HZ));
+}
+
+static void cifs_resolve_server(struct work_struct *work)
+{
+ int rc;
+ struct TCP_Server_Info *server = container_of(work,
+ struct TCP_Server_Info, resolve.work);
+
+ cifs_server_lock(server);
+
+ /*
+ * Resolve the hostname again to make sure that IP address is up-to-date.
+ */
+ rc = reconn_set_ipaddr_from_hostname(server);
+ if (rc) {
+ cifs_dbg(FYI, "%s: failed to resolve hostname: %d\n",
+ __func__, rc);
+ }
+
+ cifs_server_unlock(server);
+}
+
+/*
+ * Update the tcpStatus for the server.
+ * This is used to signal the cifsd thread to call cifs_reconnect
+ * ONLY cifsd thread should call cifs_reconnect. For any other
+ * thread, use this function
+ *
+ * @server: the tcp ses for which reconnect is needed
+ * @all_channels: if this needs to be done for all channels
+ */
+void
+cifs_signal_cifsd_for_reconnect(struct TCP_Server_Info *server,
+ bool all_channels)
+{
+ struct TCP_Server_Info *pserver;
+ struct cifs_ses *ses;
+ int i;
+
+ /* If server is a channel, select the primary channel */
+ pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
+
+ /* if we need to signal just this channel */
+ if (!all_channels) {
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus != CifsExiting)
+ server->tcpStatus = CifsNeedReconnect;
+ spin_unlock(&server->srv_lock);
+ return;
+ }
+
+ spin_lock(&cifs_tcp_ses_lock);
+ list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
+ spin_lock(&ses->chan_lock);
+ for (i = 0; i < ses->chan_count; i++) {
+ spin_lock(&ses->chans[i].server->srv_lock);
+ ses->chans[i].server->tcpStatus = CifsNeedReconnect;
+ spin_unlock(&ses->chans[i].server->srv_lock);
+ }
+ spin_unlock(&ses->chan_lock);
+ }
+ spin_unlock(&cifs_tcp_ses_lock);
+}
+
+/*
+ * Mark all sessions and tcons for reconnect.
+ * IMPORTANT: make sure that this gets called only from
+ * cifsd thread. For any other thread, use
+ * cifs_signal_cifsd_for_reconnect
+ *
+ * @server: the tcp ses for which reconnect is needed
+ * @server needs to be previously set to CifsNeedReconnect.
+ * @mark_smb_session: whether even sessions need to be marked
+ */
+void
+cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info *server,
+ bool mark_smb_session)
+{
+ struct TCP_Server_Info *pserver;
+ struct cifs_ses *ses, *nses;
+ struct cifs_tcon *tcon;
+
+ /*
+ * before reconnecting the tcp session, mark the smb session (uid) and the tid bad so they
+ * are not used until reconnected.
+ */
+ cifs_dbg(FYI, "%s: marking necessary sessions and tcons for reconnect\n", __func__);
+
+ /* If server is a channel, select the primary channel */
+ pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
+
+
+ spin_lock(&cifs_tcp_ses_lock);
+ list_for_each_entry_safe(ses, nses, &pserver->smb_ses_list, smb_ses_list) {
+ /* check if iface is still active */
+ spin_lock(&ses->chan_lock);
+ if (!cifs_chan_is_iface_active(ses, server)) {
+ spin_unlock(&ses->chan_lock);
+ cifs_chan_update_iface(ses, server);
+ spin_lock(&ses->chan_lock);
+ }
+
+ if (!mark_smb_session && cifs_chan_needs_reconnect(ses, server)) {
+ spin_unlock(&ses->chan_lock);
+ continue;
+ }
+
+ if (mark_smb_session)
+ CIFS_SET_ALL_CHANS_NEED_RECONNECT(ses);
+ else
+ cifs_chan_set_need_reconnect(ses, server);
+
+ cifs_dbg(FYI, "%s: channel connect bitmap: 0x%lx\n",
+ __func__, ses->chans_need_reconnect);
+
+ /* If all channels need reconnect, then tcon needs reconnect */
+ if (!mark_smb_session && !CIFS_ALL_CHANS_NEED_RECONNECT(ses)) {
+ spin_unlock(&ses->chan_lock);
+ continue;
+ }
+ spin_unlock(&ses->chan_lock);
+
+ spin_lock(&ses->ses_lock);
+ ses->ses_status = SES_NEED_RECON;
+ spin_unlock(&ses->ses_lock);
+
+ list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
+ tcon->need_reconnect = true;
+ spin_lock(&tcon->tc_lock);
+ tcon->status = TID_NEED_RECON;
+ spin_unlock(&tcon->tc_lock);
+ }
+ if (ses->tcon_ipc) {
+ ses->tcon_ipc->need_reconnect = true;
+ spin_lock(&ses->tcon_ipc->tc_lock);
+ ses->tcon_ipc->status = TID_NEED_RECON;
+ spin_unlock(&ses->tcon_ipc->tc_lock);
+ }
+ }
+ spin_unlock(&cifs_tcp_ses_lock);
+}
+
+static void
+cifs_abort_connection(struct TCP_Server_Info *server)
+{
+ struct mid_q_entry *mid, *nmid;
+ struct list_head retry_list;
+
+ server->maxBuf = 0;
+ server->max_read = 0;
+
+ /* do not want to be sending data on a socket we are freeing */
+ cifs_dbg(FYI, "%s: tearing down socket\n", __func__);
+ cifs_server_lock(server);
+ if (server->ssocket) {
+ cifs_dbg(FYI, "State: 0x%x Flags: 0x%lx\n", server->ssocket->state,
+ server->ssocket->flags);
+ kernel_sock_shutdown(server->ssocket, SHUT_WR);
+ cifs_dbg(FYI, "Post shutdown state: 0x%x Flags: 0x%lx\n", server->ssocket->state,
+ server->ssocket->flags);
+ sock_release(server->ssocket);
+ server->ssocket = NULL;
+ }
+ server->sequence_number = 0;
+ server->session_estab = false;
+ kfree_sensitive(server->session_key.response);
+ server->session_key.response = NULL;
+ server->session_key.len = 0;
+ server->lstrp = jiffies;
+
+ /* mark submitted MIDs for retry and issue callback */
+ INIT_LIST_HEAD(&retry_list);
+ cifs_dbg(FYI, "%s: moving mids to private list\n", __func__);
+ spin_lock(&server->mid_lock);
+ list_for_each_entry_safe(mid, nmid, &server->pending_mid_q, qhead) {
+ kref_get(&mid->refcount);
+ if (mid->mid_state == MID_REQUEST_SUBMITTED)
+ mid->mid_state = MID_RETRY_NEEDED;
+ list_move(&mid->qhead, &retry_list);
+ mid->mid_flags |= MID_DELETED;
+ }
+ spin_unlock(&server->mid_lock);
+ cifs_server_unlock(server);
+
+ cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__);
+ list_for_each_entry_safe(mid, nmid, &retry_list, qhead) {
+ list_del_init(&mid->qhead);
+ mid->callback(mid);
+ release_mid(mid);
+ }
+
+ if (cifs_rdma_enabled(server)) {
+ cifs_server_lock(server);
+ smbd_destroy(server);
+ cifs_server_unlock(server);
+ }
+}
+
+static bool cifs_tcp_ses_needs_reconnect(struct TCP_Server_Info *server, int num_targets)
+{
+ spin_lock(&server->srv_lock);
+ server->nr_targets = num_targets;
+ if (server->tcpStatus == CifsExiting) {
+ /* the demux thread will exit normally next time through the loop */
+ spin_unlock(&server->srv_lock);
+ wake_up(&server->response_q);
+ return false;
+ }
+
+ cifs_dbg(FYI, "Mark tcp session as need reconnect\n");
+ trace_smb3_reconnect(server->CurrentMid, server->conn_id,
+ server->hostname);
+ server->tcpStatus = CifsNeedReconnect;
+
+ spin_unlock(&server->srv_lock);
+ return true;
+}
+
+/*
+ * cifs tcp session reconnection
+ *
+ * mark tcp session as reconnecting so temporarily locked
+ * mark all smb sessions as reconnecting for tcp session
+ * reconnect tcp session
+ * wake up waiters on reconnection? - (not needed currently)
+ *
+ * if mark_smb_session is passed as true, unconditionally mark
+ * the smb session (and tcon) for reconnect as well. This value
+ * doesn't really matter for non-multichannel scenario.
+ *
+ */
+static int __cifs_reconnect(struct TCP_Server_Info *server,
+ bool mark_smb_session)
+{
+ int rc = 0;
+
+ if (!cifs_tcp_ses_needs_reconnect(server, 1))
+ return 0;
+
+ cifs_mark_tcp_ses_conns_for_reconnect(server, mark_smb_session);
+
+ cifs_abort_connection(server);
+
+ do {
+ try_to_freeze();
+ cifs_server_lock(server);
+
+ if (!cifs_swn_set_server_dstaddr(server)) {
+ /* resolve the hostname again to make sure that IP address is up-to-date */
+ rc = reconn_set_ipaddr_from_hostname(server);
+ cifs_dbg(FYI, "%s: reconn_set_ipaddr_from_hostname: rc=%d\n", __func__, rc);
+ }
+
+ if (cifs_rdma_enabled(server))
+ rc = smbd_reconnect(server);
+ else
+ rc = generic_ip_connect(server);
+ if (rc) {
+ cifs_server_unlock(server);
+ cifs_dbg(FYI, "%s: reconnect error %d\n", __func__, rc);
+ msleep(3000);
+ } else {
+ atomic_inc(&tcpSesReconnectCount);
+ set_credits(server, 1);
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus != CifsExiting)
+ server->tcpStatus = CifsNeedNegotiate;
+ spin_unlock(&server->srv_lock);
+ cifs_swn_reset_server_dstaddr(server);
+ cifs_server_unlock(server);
+ mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
+ }
+ } while (server->tcpStatus == CifsNeedReconnect);
+
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus == CifsNeedNegotiate)
+ mod_delayed_work(cifsiod_wq, &server->echo, 0);
+ spin_unlock(&server->srv_lock);
+
+ wake_up(&server->response_q);
+ return rc;
+}
+
+#ifdef CONFIG_CIFS_DFS_UPCALL
+static int __reconnect_target_unlocked(struct TCP_Server_Info *server, const char *target)
+{
+ int rc;
+ char *hostname;
+
+ if (!cifs_swn_set_server_dstaddr(server)) {
+ if (server->hostname != target) {
+ hostname = extract_hostname(target);
+ if (!IS_ERR(hostname)) {
+ spin_lock(&server->srv_lock);
+ kfree(server->hostname);
+ server->hostname = hostname;
+ spin_unlock(&server->srv_lock);
+ } else {
+ cifs_dbg(FYI, "%s: couldn't extract hostname or address from dfs target: %ld\n",
+ __func__, PTR_ERR(hostname));
+ cifs_dbg(FYI, "%s: default to last target server: %s\n", __func__,
+ server->hostname);
+ }
+ }
+ /* resolve the hostname again to make sure that IP address is up-to-date. */
+ rc = reconn_set_ipaddr_from_hostname(server);
+ cifs_dbg(FYI, "%s: reconn_set_ipaddr_from_hostname: rc=%d\n", __func__, rc);
+ }
+ /* Reconnect the socket */
+ if (cifs_rdma_enabled(server))
+ rc = smbd_reconnect(server);
+ else
+ rc = generic_ip_connect(server);
+
+ return rc;
+}
+
+static int reconnect_target_unlocked(struct TCP_Server_Info *server, struct dfs_cache_tgt_list *tl,
+ struct dfs_cache_tgt_iterator **target_hint)
+{
+ int rc;
+ struct dfs_cache_tgt_iterator *tit;
+
+ *target_hint = NULL;
+
+ /* If dfs target list is empty, then reconnect to last server */
+ tit = dfs_cache_get_tgt_iterator(tl);
+ if (!tit)
+ return __reconnect_target_unlocked(server, server->hostname);
+
+ /* Otherwise, try every dfs target in @tl */
+ for (; tit; tit = dfs_cache_get_next_tgt(tl, tit)) {
+ rc = __reconnect_target_unlocked(server, dfs_cache_get_tgt_name(tit));
+ if (!rc) {
+ *target_hint = tit;
+ break;
+ }
+ }
+ return rc;
+}
+
+static int reconnect_dfs_server(struct TCP_Server_Info *server)
+{
+ int rc = 0;
+ const char *refpath = server->current_fullpath + 1;
+ struct dfs_cache_tgt_list tl = DFS_CACHE_TGT_LIST_INIT(tl);
+ struct dfs_cache_tgt_iterator *target_hint = NULL;
+ int num_targets = 0;
+
+ /*
+ * Determine the number of dfs targets the referral path in @cifs_sb resolves to.
+ *
+ * smb2_reconnect() needs to know how long it should wait based upon the number of dfs
+ * targets (server->nr_targets). It's also possible that the cached referral was cleared
+ * through /proc/fs/cifs/dfscache or the target list is empty due to server settings after
+ * refreshing the referral, so, in this case, default it to 1.
+ */
+ if (!dfs_cache_noreq_find(refpath, NULL, &tl))
+ num_targets = dfs_cache_get_nr_tgts(&tl);
+ if (!num_targets)
+ num_targets = 1;
+
+ if (!cifs_tcp_ses_needs_reconnect(server, num_targets))
+ return 0;
+
+ /*
+ * Unconditionally mark all sessions & tcons for reconnect as we might be connecting to a
+ * different server or share during failover. It could be improved by adding some logic to
+ * only do that in case it connects to a different server or share, though.
+ */
+ cifs_mark_tcp_ses_conns_for_reconnect(server, true);
+
+ cifs_abort_connection(server);
+
+ do {
+ try_to_freeze();
+ cifs_server_lock(server);
+
+ rc = reconnect_target_unlocked(server, &tl, &target_hint);
+ if (rc) {
+ /* Failed to reconnect socket */
+ cifs_server_unlock(server);
+ cifs_dbg(FYI, "%s: reconnect error %d\n", __func__, rc);
+ msleep(3000);
+ continue;
+ }
+ /*
+ * Socket was created. Update tcp session status to CifsNeedNegotiate so that a
+ * process waiting for reconnect will know it needs to re-establish session and tcon
+ * through the reconnected target server.
+ */
+ atomic_inc(&tcpSesReconnectCount);
+ set_credits(server, 1);
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus != CifsExiting)
+ server->tcpStatus = CifsNeedNegotiate;
+ spin_unlock(&server->srv_lock);
+ cifs_swn_reset_server_dstaddr(server);
+ cifs_server_unlock(server);
+ mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
+ } while (server->tcpStatus == CifsNeedReconnect);
+
+ if (target_hint)
+ dfs_cache_noreq_update_tgthint(refpath, target_hint);
+
+ dfs_cache_free_tgts(&tl);
+
+ /* Need to set up echo worker again once connection has been established */
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus == CifsNeedNegotiate)
+ mod_delayed_work(cifsiod_wq, &server->echo, 0);
+ spin_unlock(&server->srv_lock);
+
+ wake_up(&server->response_q);
+ return rc;
+}
+
+int cifs_reconnect(struct TCP_Server_Info *server, bool mark_smb_session)
+{
+ /* If tcp session is not an dfs connection, then reconnect to last target server */
+ spin_lock(&server->srv_lock);
+ if (!server->is_dfs_conn) {
+ spin_unlock(&server->srv_lock);
+ return __cifs_reconnect(server, mark_smb_session);
+ }
+ spin_unlock(&server->srv_lock);
+
+ mutex_lock(&server->refpath_lock);
+ if (!server->origin_fullpath || !server->leaf_fullpath) {
+ mutex_unlock(&server->refpath_lock);
+ return __cifs_reconnect(server, mark_smb_session);
+ }
+ mutex_unlock(&server->refpath_lock);
+
+ return reconnect_dfs_server(server);
+}
+#else
+int cifs_reconnect(struct TCP_Server_Info *server, bool mark_smb_session)
+{
+ return __cifs_reconnect(server, mark_smb_session);
+}
+#endif
+
+static void
+cifs_echo_request(struct work_struct *work)
+{
+ int rc;
+ struct TCP_Server_Info *server = container_of(work,
+ struct TCP_Server_Info, echo.work);
+
+ /*
+ * We cannot send an echo if it is disabled.
+ * Also, no need to ping if we got a response recently.
+ */
+
+ if (server->tcpStatus == CifsNeedReconnect ||
+ server->tcpStatus == CifsExiting ||
+ server->tcpStatus == CifsNew ||
+ (server->ops->can_echo && !server->ops->can_echo(server)) ||
+ time_before(jiffies, server->lstrp + server->echo_interval - HZ))
+ goto requeue_echo;
+
+ rc = server->ops->echo ? server->ops->echo(server) : -ENOSYS;
+ cifs_server_dbg(FYI, "send echo request: rc = %d\n", rc);
+
+ /* Check witness registrations */
+ cifs_swn_check();
+
+requeue_echo:
+ queue_delayed_work(cifsiod_wq, &server->echo, server->echo_interval);
+}
+
+static bool
+allocate_buffers(struct TCP_Server_Info *server)
+{
+ if (!server->bigbuf) {
+ server->bigbuf = (char *)cifs_buf_get();
+ if (!server->bigbuf) {
+ cifs_server_dbg(VFS, "No memory for large SMB response\n");
+ msleep(3000);
+ /* retry will check if exiting */
+ return false;
+ }
+ } else if (server->large_buf) {
+ /* we are reusing a dirty large buf, clear its start */
+ memset(server->bigbuf, 0, HEADER_SIZE(server));
+ }
+
+ if (!server->smallbuf) {
+ server->smallbuf = (char *)cifs_small_buf_get();
+ if (!server->smallbuf) {
+ cifs_server_dbg(VFS, "No memory for SMB response\n");
+ msleep(1000);
+ /* retry will check if exiting */
+ return false;
+ }
+ /* beginning of smb buffer is cleared in our buf_get */
+ } else {
+ /* if existing small buf clear beginning */
+ memset(server->smallbuf, 0, HEADER_SIZE(server));
+ }
+
+ return true;
+}
+
+static bool
+server_unresponsive(struct TCP_Server_Info *server)
+{
+ /*
+ * We need to wait 3 echo intervals to make sure we handle such
+ * situations right:
+ * 1s client sends a normal SMB request
+ * 2s client gets a response
+ * 30s echo workqueue job pops, and decides we got a response recently
+ * and don't need to send another
+ * ...
+ * 65s kernel_recvmsg times out, and we see that we haven't gotten
+ * a response in >60s.
+ */
+ spin_lock(&server->srv_lock);
+ if ((server->tcpStatus == CifsGood ||
+ server->tcpStatus == CifsNeedNegotiate) &&
+ (!server->ops->can_echo || server->ops->can_echo(server)) &&
+ time_after(jiffies, server->lstrp + 3 * server->echo_interval)) {
+ spin_unlock(&server->srv_lock);
+ cifs_server_dbg(VFS, "has not responded in %lu seconds. Reconnecting...\n",
+ (3 * server->echo_interval) / HZ);
+ cifs_reconnect(server, false);
+ return true;
+ }
+ spin_unlock(&server->srv_lock);
+
+ return false;
+}
+
+static inline bool
+zero_credits(struct TCP_Server_Info *server)
+{
+ int val;
+
+ spin_lock(&server->req_lock);
+ val = server->credits + server->echo_credits + server->oplock_credits;
+ if (server->in_flight == 0 && val == 0) {
+ spin_unlock(&server->req_lock);
+ return true;
+ }
+ spin_unlock(&server->req_lock);
+ return false;
+}
+
+static int
+cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg)
+{
+ int length = 0;
+ int total_read;
+
+ for (total_read = 0; msg_data_left(smb_msg); total_read += length) {
+ try_to_freeze();
+
+ /* reconnect if no credits and no requests in flight */
+ if (zero_credits(server)) {
+ cifs_reconnect(server, false);
+ return -ECONNABORTED;
+ }
+
+ if (server_unresponsive(server))
+ return -ECONNABORTED;
+ if (cifs_rdma_enabled(server) && server->smbd_conn)
+ length = smbd_recv(server->smbd_conn, smb_msg);
+ else
+ length = sock_recvmsg(server->ssocket, smb_msg, 0);
+
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus == CifsExiting) {
+ spin_unlock(&server->srv_lock);
+ return -ESHUTDOWN;
+ }
+
+ if (server->tcpStatus == CifsNeedReconnect) {
+ spin_unlock(&server->srv_lock);
+ cifs_reconnect(server, false);
+ return -ECONNABORTED;
+ }
+ spin_unlock(&server->srv_lock);
+
+ if (length == -ERESTARTSYS ||
+ length == -EAGAIN ||
+ length == -EINTR) {
+ /*
+ * Minimum sleep to prevent looping, allowing socket
+ * to clear and app threads to set tcpStatus
+ * CifsNeedReconnect if server hung.
+ */
+ usleep_range(1000, 2000);
+ length = 0;
+ continue;
+ }
+
+ if (length <= 0) {
+ cifs_dbg(FYI, "Received no data or error: %d\n", length);
+ cifs_reconnect(server, false);
+ return -ECONNABORTED;
+ }
+ }
+ return total_read;
+}
+
+int
+cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
+ unsigned int to_read)
+{
+ struct msghdr smb_msg = {};
+ struct kvec iov = {.iov_base = buf, .iov_len = to_read};
+ iov_iter_kvec(&smb_msg.msg_iter, ITER_DEST, &iov, 1, to_read);
+
+ return cifs_readv_from_socket(server, &smb_msg);
+}
+
+ssize_t
+cifs_discard_from_socket(struct TCP_Server_Info *server, size_t to_read)
+{
+ struct msghdr smb_msg = {};
+
+ /*
+ * iov_iter_discard already sets smb_msg.type and count and iov_offset
+ * and cifs_readv_from_socket sets msg_control and msg_controllen
+ * so little to initialize in struct msghdr
+ */
+ iov_iter_discard(&smb_msg.msg_iter, ITER_DEST, to_read);
+
+ return cifs_readv_from_socket(server, &smb_msg);
+}
+
+int
+cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
+ unsigned int page_offset, unsigned int to_read)
+{
+ struct msghdr smb_msg = {};
+ struct bio_vec bv = {
+ .bv_page = page, .bv_len = to_read, .bv_offset = page_offset};
+ iov_iter_bvec(&smb_msg.msg_iter, ITER_DEST, &bv, 1, to_read);
+ return cifs_readv_from_socket(server, &smb_msg);
+}
+
+static bool
+is_smb_response(struct TCP_Server_Info *server, unsigned char type)
+{
+ /*
+ * The first byte big endian of the length field,
+ * is actually not part of the length but the type
+ * with the most common, zero, as regular data.
+ */
+ switch (type) {
+ case RFC1002_SESSION_MESSAGE:
+ /* Regular SMB response */
+ return true;
+ case RFC1002_SESSION_KEEP_ALIVE:
+ cifs_dbg(FYI, "RFC 1002 session keep alive\n");
+ break;
+ case RFC1002_POSITIVE_SESSION_RESPONSE:
+ cifs_dbg(FYI, "RFC 1002 positive session response\n");
+ break;
+ case RFC1002_NEGATIVE_SESSION_RESPONSE:
+ /*
+ * We get this from Windows 98 instead of an error on
+ * SMB negprot response.
+ */
+ cifs_dbg(FYI, "RFC 1002 negative session response\n");
+ /* give server a second to clean up */
+ msleep(1000);
+ /*
+ * Always try 445 first on reconnect since we get NACK
+ * on some if we ever connected to port 139 (the NACK
+ * is since we do not begin with RFC1001 session
+ * initialize frame).
+ */
+ cifs_set_port((struct sockaddr *)&server->dstaddr, CIFS_PORT);
+ cifs_reconnect(server, true);
+ break;
+ default:
+ cifs_server_dbg(VFS, "RFC 1002 unknown response type 0x%x\n", type);
+ cifs_reconnect(server, true);
+ }
+
+ return false;
+}
+
+void
+dequeue_mid(struct mid_q_entry *mid, bool malformed)
+{
+#ifdef CONFIG_CIFS_STATS2
+ mid->when_received = jiffies;
+#endif
+ spin_lock(&mid->server->mid_lock);
+ if (!malformed)
+ mid->mid_state = MID_RESPONSE_RECEIVED;
+ else
+ mid->mid_state = MID_RESPONSE_MALFORMED;
+ /*
+ * Trying to handle/dequeue a mid after the send_recv()
+ * function has finished processing it is a bug.
+ */
+ if (mid->mid_flags & MID_DELETED) {
+ spin_unlock(&mid->server->mid_lock);
+ pr_warn_once("trying to dequeue a deleted mid\n");
+ } else {
+ list_del_init(&mid->qhead);
+ mid->mid_flags |= MID_DELETED;
+ spin_unlock(&mid->server->mid_lock);
+ }
+}
+
+static unsigned int
+smb2_get_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
+{
+ struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
+
+ /*
+ * SMB1 does not use credits.
+ */
+ if (is_smb1(server))
+ return 0;
+
+ return le16_to_cpu(shdr->CreditRequest);
+}
+
+static void
+handle_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server,
+ char *buf, int malformed)
+{
+ if (server->ops->check_trans2 &&
+ server->ops->check_trans2(mid, server, buf, malformed))
+ return;
+ mid->credits_received = smb2_get_credits_from_hdr(buf, server);
+ mid->resp_buf = buf;
+ mid->large_buf = server->large_buf;
+ /* Was previous buf put in mpx struct for multi-rsp? */
+ if (!mid->multiRsp) {
+ /* smb buffer will be freed by user thread */
+ if (server->large_buf)
+ server->bigbuf = NULL;
+ else
+ server->smallbuf = NULL;
+ }
+ dequeue_mid(mid, malformed);
+}
+
+int
+cifs_enable_signing(struct TCP_Server_Info *server, bool mnt_sign_required)
+{
+ bool srv_sign_required = server->sec_mode & server->vals->signing_required;
+ bool srv_sign_enabled = server->sec_mode & server->vals->signing_enabled;
+ bool mnt_sign_enabled;
+
+ /*
+ * Is signing required by mnt options? If not then check
+ * global_secflags to see if it is there.
+ */
+ if (!mnt_sign_required)
+ mnt_sign_required = ((global_secflags & CIFSSEC_MUST_SIGN) ==
+ CIFSSEC_MUST_SIGN);
+
+ /*
+ * If signing is required then it's automatically enabled too,
+ * otherwise, check to see if the secflags allow it.
+ */
+ mnt_sign_enabled = mnt_sign_required ? mnt_sign_required :
+ (global_secflags & CIFSSEC_MAY_SIGN);
+
+ /* If server requires signing, does client allow it? */
+ if (srv_sign_required) {
+ if (!mnt_sign_enabled) {
+ cifs_dbg(VFS, "Server requires signing, but it's disabled in SecurityFlags!\n");
+ return -EOPNOTSUPP;
+ }
+ server->sign = true;
+ }
+
+ /* If client requires signing, does server allow it? */
+ if (mnt_sign_required) {
+ if (!srv_sign_enabled) {
+ cifs_dbg(VFS, "Server does not support signing!\n");
+ return -EOPNOTSUPP;
+ }
+ server->sign = true;
+ }
+
+ if (cifs_rdma_enabled(server) && server->sign)
+ cifs_dbg(VFS, "Signing is enabled, and RDMA read/write will be disabled\n");
+
+ return 0;
+}
+
+
+static void clean_demultiplex_info(struct TCP_Server_Info *server)
+{
+ int length;
+
+ /* take it off the list, if it's not already */
+ spin_lock(&server->srv_lock);
+ list_del_init(&server->tcp_ses_list);
+ spin_unlock(&server->srv_lock);
+
+ cancel_delayed_work_sync(&server->echo);
+ cancel_delayed_work_sync(&server->resolve);
+
+ spin_lock(&server->srv_lock);
+ server->tcpStatus = CifsExiting;
+ spin_unlock(&server->srv_lock);
+ wake_up_all(&server->response_q);
+
+ /* check if we have blocked requests that need to free */
+ spin_lock(&server->req_lock);
+ if (server->credits <= 0)
+ server->credits = 1;
+ spin_unlock(&server->req_lock);
+ /*
+ * Although there should not be any requests blocked on this queue it
+ * can not hurt to be paranoid and try to wake up requests that may
+ * haven been blocked when more than 50 at time were on the wire to the
+ * same server - they now will see the session is in exit state and get
+ * out of SendReceive.
+ */
+ wake_up_all(&server->request_q);
+ /* give those requests time to exit */
+ msleep(125);
+ if (cifs_rdma_enabled(server))
+ smbd_destroy(server);
+ if (server->ssocket) {
+ sock_release(server->ssocket);
+ server->ssocket = NULL;
+ }
+
+ if (!list_empty(&server->pending_mid_q)) {
+ struct list_head dispose_list;
+ struct mid_q_entry *mid_entry;
+ struct list_head *tmp, *tmp2;
+
+ INIT_LIST_HEAD(&dispose_list);
+ spin_lock(&server->mid_lock);
+ list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
+ mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
+ cifs_dbg(FYI, "Clearing mid %llu\n", mid_entry->mid);
+ kref_get(&mid_entry->refcount);
+ mid_entry->mid_state = MID_SHUTDOWN;
+ list_move(&mid_entry->qhead, &dispose_list);
+ mid_entry->mid_flags |= MID_DELETED;
+ }
+ spin_unlock(&server->mid_lock);
+
+ /* now walk dispose list and issue callbacks */
+ list_for_each_safe(tmp, tmp2, &dispose_list) {
+ mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
+ cifs_dbg(FYI, "Callback mid %llu\n", mid_entry->mid);
+ list_del_init(&mid_entry->qhead);
+ mid_entry->callback(mid_entry);
+ release_mid(mid_entry);
+ }
+ /* 1/8th of sec is more than enough time for them to exit */
+ msleep(125);
+ }
+
+ if (!list_empty(&server->pending_mid_q)) {
+ /*
+ * mpx threads have not exited yet give them at least the smb
+ * send timeout time for long ops.
+ *
+ * Due to delays on oplock break requests, we need to wait at
+ * least 45 seconds before giving up on a request getting a
+ * response and going ahead and killing cifsd.
+ */
+ cifs_dbg(FYI, "Wait for exit from demultiplex thread\n");
+ msleep(46000);
+ /*
+ * If threads still have not exited they are probably never
+ * coming home not much else we can do but free the memory.
+ */
+ }
+
+#ifdef CONFIG_CIFS_DFS_UPCALL
+ kfree(server->origin_fullpath);
+ kfree(server->leaf_fullpath);
+#endif
+ kfree(server);
+
+ length = atomic_dec_return(&tcpSesAllocCount);
+ if (length > 0)
+ mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
+}
+
+static int
+standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
+{
+ int length;
+ char *buf = server->smallbuf;
+ unsigned int pdu_length = server->pdu_size;
+
+ /* make sure this will fit in a large buffer */
+ if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) -
+ HEADER_PREAMBLE_SIZE(server)) {
+ cifs_server_dbg(VFS, "SMB response too long (%u bytes)\n", pdu_length);
+ cifs_reconnect(server, true);
+ return -ECONNABORTED;
+ }
+
+ /* switch to large buffer if too big for a small one */
+ if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {
+ server->large_buf = true;
+ memcpy(server->bigbuf, buf, server->total_read);
+ buf = server->bigbuf;
+ }
+
+ /* now read the rest */
+ length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
+ pdu_length - MID_HEADER_SIZE(server));
+
+ if (length < 0)
+ return length;
+ server->total_read += length;
+
+ dump_smb(buf, server->total_read);
+
+ return cifs_handle_standard(server, mid);
+}
+
+int
+cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
+{
+ char *buf = server->large_buf ? server->bigbuf : server->smallbuf;
+ int rc;
+
+ /*
+ * We know that we received enough to get to the MID as we
+ * checked the pdu_length earlier. Now check to see
+ * if the rest of the header is OK.
+ *
+ * 48 bytes is enough to display the header and a little bit
+ * into the payload for debugging purposes.
+ */
+ rc = server->ops->check_message(buf, server->total_read, server);
+ if (rc)
+ cifs_dump_mem("Bad SMB: ", buf,
+ min_t(unsigned int, server->total_read, 48));
+
+ if (server->ops->is_session_expired &&
+ server->ops->is_session_expired(buf)) {
+ cifs_reconnect(server, true);
+ return -1;
+ }
+
+ if (server->ops->is_status_pending &&
+ server->ops->is_status_pending(buf, server))
+ return -1;
+
+ if (!mid)
+ return rc;
+
+ handle_mid(mid, server, buf, rc);
+ return 0;
+}
+
+static void
+smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
+{
+ struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
+ int scredits, in_flight;
+
+ /*
+ * SMB1 does not use credits.
+ */
+ if (is_smb1(server))
+ return;
+
+ if (shdr->CreditRequest) {
+ spin_lock(&server->req_lock);
+ server->credits += le16_to_cpu(shdr->CreditRequest);
+ scredits = server->credits;
+ in_flight = server->in_flight;
+ spin_unlock(&server->req_lock);
+ wake_up(&server->request_q);
+
+ trace_smb3_hdr_credits(server->CurrentMid,
+ server->conn_id, server->hostname, scredits,
+ le16_to_cpu(shdr->CreditRequest), in_flight);
+ cifs_server_dbg(FYI, "%s: added %u credits total=%d\n",
+ __func__, le16_to_cpu(shdr->CreditRequest),
+ scredits);
+ }
+}
+
+
+static int
+cifs_demultiplex_thread(void *p)
+{
+ int i, num_mids, length;
+ struct TCP_Server_Info *server = p;
+ unsigned int pdu_length;
+ unsigned int next_offset;
+ char *buf = NULL;
+ struct task_struct *task_to_wake = NULL;
+ struct mid_q_entry *mids[MAX_COMPOUND];
+ char *bufs[MAX_COMPOUND];
+ unsigned int noreclaim_flag, num_io_timeout = 0;
+ bool pending_reconnect = false;
+
+ noreclaim_flag = memalloc_noreclaim_save();
+ cifs_dbg(FYI, "Demultiplex PID: %d\n", task_pid_nr(current));
+
+ length = atomic_inc_return(&tcpSesAllocCount);
+ if (length > 1)
+ mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
+
+ set_freezable();
+ allow_kernel_signal(SIGKILL);
+ while (server->tcpStatus != CifsExiting) {
+ if (try_to_freeze())
+ continue;
+
+ if (!allocate_buffers(server))
+ continue;
+
+ server->large_buf = false;
+ buf = server->smallbuf;
+ pdu_length = 4; /* enough to get RFC1001 header */
+
+ length = cifs_read_from_socket(server, buf, pdu_length);
+ if (length < 0)
+ continue;
+
+ if (is_smb1(server))
+ server->total_read = length;
+ else
+ server->total_read = 0;
+
+ /*
+ * The right amount was read from socket - 4 bytes,
+ * so we can now interpret the length field.
+ */
+ pdu_length = get_rfc1002_length(buf);
+
+ cifs_dbg(FYI, "RFC1002 header 0x%x\n", pdu_length);
+ if (!is_smb_response(server, buf[0]))
+ continue;
+
+ pending_reconnect = false;
+next_pdu:
+ server->pdu_size = pdu_length;
+
+ /* make sure we have enough to get to the MID */
+ if (server->pdu_size < MID_HEADER_SIZE(server)) {
+ cifs_server_dbg(VFS, "SMB response too short (%u bytes)\n",
+ server->pdu_size);
+ cifs_reconnect(server, true);
+ continue;
+ }
+
+ /* read down to the MID */
+ length = cifs_read_from_socket(server,
+ buf + HEADER_PREAMBLE_SIZE(server),
+ MID_HEADER_SIZE(server));
+ if (length < 0)
+ continue;
+ server->total_read += length;
+
+ if (server->ops->next_header) {
+ if (server->ops->next_header(server, buf, &next_offset)) {
+ cifs_dbg(VFS, "%s: malformed response (next_offset=%u)\n",
+ __func__, next_offset);
+ cifs_reconnect(server, true);
+ continue;
+ }
+ if (next_offset)
+ server->pdu_size = next_offset;
+ }
+
+ memset(mids, 0, sizeof(mids));
+ memset(bufs, 0, sizeof(bufs));
+ num_mids = 0;
+
+ if (server->ops->is_transform_hdr &&
+ server->ops->receive_transform &&
+ server->ops->is_transform_hdr(buf)) {
+ length = server->ops->receive_transform(server,
+ mids,
+ bufs,
+ &num_mids);
+ } else {
+ mids[0] = server->ops->find_mid(server, buf);
+ bufs[0] = buf;
+ num_mids = 1;
+
+ if (!mids[0] || !mids[0]->receive)
+ length = standard_receive3(server, mids[0]);
+ else
+ length = mids[0]->receive(server, mids[0]);
+ }
+
+ if (length < 0) {
+ for (i = 0; i < num_mids; i++)
+ if (mids[i])
+ release_mid(mids[i]);
+ continue;
+ }
+
+ if (server->ops->is_status_io_timeout &&
+ server->ops->is_status_io_timeout(buf)) {
+ num_io_timeout++;
+ if (num_io_timeout > MAX_STATUS_IO_TIMEOUT) {
+ cifs_server_dbg(VFS,
+ "Number of request timeouts exceeded %d. Reconnecting",
+ MAX_STATUS_IO_TIMEOUT);
+
+ pending_reconnect = true;
+ num_io_timeout = 0;
+ }
+ }
+
+ server->lstrp = jiffies;
+
+ for (i = 0; i < num_mids; i++) {
+ if (mids[i] != NULL) {
+ mids[i]->resp_buf_size = server->pdu_size;
+
+ if (bufs[i] && server->ops->is_network_name_deleted)
+ server->ops->is_network_name_deleted(bufs[i],
+ server);
+
+ if (!mids[i]->multiRsp || mids[i]->multiEnd)
+ mids[i]->callback(mids[i]);
+
+ release_mid(mids[i]);
+ } else if (server->ops->is_oplock_break &&
+ server->ops->is_oplock_break(bufs[i],
+ server)) {
+ smb2_add_credits_from_hdr(bufs[i], server);
+ cifs_dbg(FYI, "Received oplock break\n");
+ } else {
+ cifs_server_dbg(VFS, "No task to wake, unknown frame received! NumMids %d\n",
+ atomic_read(&mid_count));
+ cifs_dump_mem("Received Data is: ", bufs[i],
+ HEADER_SIZE(server));
+ smb2_add_credits_from_hdr(bufs[i], server);
+#ifdef CONFIG_CIFS_DEBUG2
+ if (server->ops->dump_detail)
+ server->ops->dump_detail(bufs[i],
+ server);
+ cifs_dump_mids(server);
+#endif /* CIFS_DEBUG2 */
+ }
+ }
+
+ if (pdu_length > server->pdu_size) {
+ if (!allocate_buffers(server))
+ continue;
+ pdu_length -= server->pdu_size;
+ server->total_read = 0;
+ server->large_buf = false;
+ buf = server->smallbuf;
+ goto next_pdu;
+ }
+
+ /* do this reconnect at the very end after processing all MIDs */
+ if (pending_reconnect)
+ cifs_reconnect(server, true);
+
+ } /* end while !EXITING */
+
+ /* buffer usually freed in free_mid - need to free it here on exit */
+ cifs_buf_release(server->bigbuf);
+ if (server->smallbuf) /* no sense logging a debug message if NULL */
+ cifs_small_buf_release(server->smallbuf);
+
+ task_to_wake = xchg(&server->tsk, NULL);
+ clean_demultiplex_info(server);
+
+ /* if server->tsk was NULL then wait for a signal before exiting */
+ if (!task_to_wake) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ while (!signal_pending(current)) {
+ schedule();
+ set_current_state(TASK_INTERRUPTIBLE);
+ }
+ set_current_state(TASK_RUNNING);
+ }
+
+ memalloc_noreclaim_restore(noreclaim_flag);
+ module_put_and_kthread_exit(0);
+}
+
+int
+cifs_ipaddr_cmp(struct sockaddr *srcaddr, struct sockaddr *rhs)
+{
+ struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
+ struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
+ struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
+ struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
+
+ switch (srcaddr->sa_family) {
+ case AF_UNSPEC:
+ switch (rhs->sa_family) {
+ case AF_UNSPEC:
+ return 0;
+ case AF_INET:
+ case AF_INET6:
+ return 1;
+ default:
+ return -1;
+ }
+ case AF_INET: {
+ switch (rhs->sa_family) {
+ case AF_UNSPEC:
+ return -1;
+ case AF_INET:
+ return memcmp(saddr4, vaddr4,
+ sizeof(struct sockaddr_in));
+ case AF_INET6:
+ return 1;
+ default:
+ return -1;
+ }
+ }
+ case AF_INET6: {
+ switch (rhs->sa_family) {
+ case AF_UNSPEC:
+ case AF_INET:
+ return -1;
+ case AF_INET6:
+ return memcmp(saddr6,
+ vaddr6,
+ sizeof(struct sockaddr_in6));
+ default:
+ return -1;
+ }
+ }
+ default:
+ return -1; /* don't expect to be here */
+ }
+}
+
+/*
+ * Returns true if srcaddr isn't specified and rhs isn't specified, or
+ * if srcaddr is specified and matches the IP address of the rhs argument
+ */
+bool
+cifs_match_ipaddr(struct sockaddr *srcaddr, struct sockaddr *rhs)
+{
+ switch (srcaddr->sa_family) {
+ case AF_UNSPEC:
+ return (rhs->sa_family == AF_UNSPEC);
+ case AF_INET: {
+ struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
+ struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
+ return (saddr4->sin_addr.s_addr == vaddr4->sin_addr.s_addr);
+ }
+ case AF_INET6: {
+ struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
+ struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
+ return ipv6_addr_equal(&saddr6->sin6_addr, &vaddr6->sin6_addr);
+ }
+ default:
+ WARN_ON(1);
+ return false; /* don't expect to be here */
+ }
+}
+
+/*
+ * If no port is specified in addr structure, we try to match with 445 port
+ * and if it fails - with 139 ports. It should be called only if address
+ * families of server and addr are equal.
+ */
+static bool
+match_port(struct TCP_Server_Info *server, struct sockaddr *addr)
+{
+ __be16 port, *sport;
+
+ /* SMBDirect manages its own ports, don't match it here */
+ if (server->rdma)
+ return true;
+
+ switch (addr->sa_family) {
+ case AF_INET:
+ sport = &((struct sockaddr_in *) &server->dstaddr)->sin_port;
+ port = ((struct sockaddr_in *) addr)->sin_port;
+ break;
+ case AF_INET6:
+ sport = &((struct sockaddr_in6 *) &server->dstaddr)->sin6_port;
+ port = ((struct sockaddr_in6 *) addr)->sin6_port;
+ break;
+ default:
+ WARN_ON(1);
+ return false;
+ }
+
+ if (!port) {
+ port = htons(CIFS_PORT);
+ if (port == *sport)
+ return true;
+
+ port = htons(RFC1001_PORT);
+ }
+
+ return port == *sport;
+}
+
+static bool
+match_address(struct TCP_Server_Info *server, struct sockaddr *addr,
+ struct sockaddr *srcaddr)
+{
+ switch (addr->sa_family) {
+ case AF_INET: {
+ struct sockaddr_in *addr4 = (struct sockaddr_in *)addr;
+ struct sockaddr_in *srv_addr4 =
+ (struct sockaddr_in *)&server->dstaddr;
+
+ if (addr4->sin_addr.s_addr != srv_addr4->sin_addr.s_addr)
+ return false;
+ break;
+ }
+ case AF_INET6: {
+ struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
+ struct sockaddr_in6 *srv_addr6 =
+ (struct sockaddr_in6 *)&server->dstaddr;
+
+ if (!ipv6_addr_equal(&addr6->sin6_addr,
+ &srv_addr6->sin6_addr))
+ return false;
+ if (addr6->sin6_scope_id != srv_addr6->sin6_scope_id)
+ return false;
+ break;
+ }
+ default:
+ WARN_ON(1);
+ return false; /* don't expect to be here */
+ }
+
+ if (!cifs_match_ipaddr(srcaddr, (struct sockaddr *)&server->srcaddr))
+ return false;
+
+ return true;
+}
+
+static bool
+match_security(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
+{
+ /*
+ * The select_sectype function should either return the ctx->sectype
+ * that was specified, or "Unspecified" if that sectype was not
+ * compatible with the given NEGOTIATE request.
+ */
+ if (server->ops->select_sectype(server, ctx->sectype)
+ == Unspecified)
+ return false;
+
+ /*
+ * Now check if signing mode is acceptable. No need to check
+ * global_secflags at this point since if MUST_SIGN is set then
+ * the server->sign had better be too.
+ */
+ if (ctx->sign && !server->sign)
+ return false;
+
+ return true;
+}
+
+/* this function must be called with srv_lock held */
+static int match_server(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
+{
+ struct sockaddr *addr = (struct sockaddr *)&ctx->dstaddr;
+
+ lockdep_assert_held(&server->srv_lock);
+
+ if (ctx->nosharesock)
+ return 0;
+
+ /* this server does not share socket */
+ if (server->nosharesock)
+ return 0;
+
+ /* If multidialect negotiation see if existing sessions match one */
+ if (strcmp(ctx->vals->version_string, SMB3ANY_VERSION_STRING) == 0) {
+ if (server->vals->protocol_id < SMB30_PROT_ID)
+ return 0;
+ } else if (strcmp(ctx->vals->version_string,
+ SMBDEFAULT_VERSION_STRING) == 0) {
+ if (server->vals->protocol_id < SMB21_PROT_ID)
+ return 0;
+ } else if ((server->vals != ctx->vals) || (server->ops != ctx->ops))
+ return 0;
+
+ if (!net_eq(cifs_net_ns(server), current->nsproxy->net_ns))
+ return 0;
+
+ if (strcasecmp(server->hostname, ctx->server_hostname))
+ return 0;
+
+ if (!match_address(server, addr,
+ (struct sockaddr *)&ctx->srcaddr))
+ return 0;
+
+ if (!match_port(server, addr))
+ return 0;
+
+ if (!match_security(server, ctx))
+ return 0;
+
+ if (server->echo_interval != ctx->echo_interval * HZ)
+ return 0;
+
+ if (server->rdma != ctx->rdma)
+ return 0;
+
+ if (server->ignore_signature != ctx->ignore_signature)
+ return 0;
+
+ if (server->min_offload != ctx->min_offload)
+ return 0;
+
+ return 1;
+}
+
+struct TCP_Server_Info *
+cifs_find_tcp_session(struct smb3_fs_context *ctx)
+{
+ struct TCP_Server_Info *server;
+
+ spin_lock(&cifs_tcp_ses_lock);
+ list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
+ spin_lock(&server->srv_lock);
+#ifdef CONFIG_CIFS_DFS_UPCALL
+ /*
+ * DFS failover implementation in cifs_reconnect() requires unique tcp sessions for
+ * DFS connections to do failover properly, so avoid sharing them with regular
+ * shares or even links that may connect to same server but having completely
+ * different failover targets.
+ */
+ if (server->is_dfs_conn) {
+ spin_unlock(&server->srv_lock);
+ continue;
+ }
+#endif
+ /*
+ * Skip ses channels since they're only handled in lower layers
+ * (e.g. cifs_send_recv).
+ */
+ if (CIFS_SERVER_IS_CHAN(server) || !match_server(server, ctx)) {
+ spin_unlock(&server->srv_lock);
+ continue;
+ }
+ spin_unlock(&server->srv_lock);
+
+ ++server->srv_count;
+ spin_unlock(&cifs_tcp_ses_lock);
+ cifs_dbg(FYI, "Existing tcp session with server found\n");
+ return server;
+ }
+ spin_unlock(&cifs_tcp_ses_lock);
+ return NULL;
+}
+
+void
+cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
+{
+ struct task_struct *task;
+
+ spin_lock(&cifs_tcp_ses_lock);
+ if (--server->srv_count > 0) {
+ spin_unlock(&cifs_tcp_ses_lock);
+ return;
+ }
+
+ /* srv_count can never go negative */
+ WARN_ON(server->srv_count < 0);
+
+ put_net(cifs_net_ns(server));
+
+ list_del_init(&server->tcp_ses_list);
+ spin_unlock(&cifs_tcp_ses_lock);
+
+ /* For secondary channels, we pick up ref-count on the primary server */
+ if (CIFS_SERVER_IS_CHAN(server))
+ cifs_put_tcp_session(server->primary_server, from_reconnect);
+
+ cancel_delayed_work_sync(&server->echo);
+ cancel_delayed_work_sync(&server->resolve);
+
+ if (from_reconnect)
+ /*
+ * Avoid deadlock here: reconnect work calls
+ * cifs_put_tcp_session() at its end. Need to be sure
+ * that reconnect work does nothing with server pointer after
+ * that step.
+ */
+ cancel_delayed_work(&server->reconnect);
+ else
+ cancel_delayed_work_sync(&server->reconnect);
+
+ spin_lock(&server->srv_lock);
+ server->tcpStatus = CifsExiting;
+ spin_unlock(&server->srv_lock);
+
+ cifs_crypto_secmech_release(server);
+
+ kfree_sensitive(server->session_key.response);
+ server->session_key.response = NULL;
+ server->session_key.len = 0;
+ kfree(server->hostname);
+ server->hostname = NULL;
+
+ task = xchg(&server->tsk, NULL);
+ if (task)
+ send_sig(SIGKILL, task, 1);
+}
+
+struct TCP_Server_Info *
+cifs_get_tcp_session(struct smb3_fs_context *ctx,
+ struct TCP_Server_Info *primary_server)
+{
+ struct TCP_Server_Info *tcp_ses = NULL;
+ int rc;
+
+ cifs_dbg(FYI, "UNC: %s\n", ctx->UNC);
+
+ /* see if we already have a matching tcp_ses */
+ tcp_ses = cifs_find_tcp_session(ctx);
+ if (tcp_ses)
+ return tcp_ses;
+
+ tcp_ses = kzalloc(sizeof(struct TCP_Server_Info), GFP_KERNEL);
+ if (!tcp_ses) {
+ rc = -ENOMEM;
+ goto out_err;
+ }
+
+ tcp_ses->hostname = kstrdup(ctx->server_hostname, GFP_KERNEL);
+ if (!tcp_ses->hostname) {
+ rc = -ENOMEM;
+ goto out_err;
+ }
+
+ if (ctx->nosharesock)
+ tcp_ses->nosharesock = true;
+
+ tcp_ses->ops = ctx->ops;
+ tcp_ses->vals = ctx->vals;
+ cifs_set_net_ns(tcp_ses, get_net(current->nsproxy->net_ns));
+
+ tcp_ses->conn_id = atomic_inc_return(&tcpSesNextId);
+ tcp_ses->noblockcnt = ctx->rootfs;
+ tcp_ses->noblocksnd = ctx->noblocksnd || ctx->rootfs;
+ tcp_ses->noautotune = ctx->noautotune;
+ tcp_ses->tcp_nodelay = ctx->sockopt_tcp_nodelay;
+ tcp_ses->rdma = ctx->rdma;
+ tcp_ses->in_flight = 0;
+ tcp_ses->max_in_flight = 0;
+ tcp_ses->credits = 1;
+ if (primary_server) {
+ spin_lock(&cifs_tcp_ses_lock);
+ ++primary_server->srv_count;
+ spin_unlock(&cifs_tcp_ses_lock);
+ tcp_ses->primary_server = primary_server;
+ }
+ init_waitqueue_head(&tcp_ses->response_q);
+ init_waitqueue_head(&tcp_ses->request_q);
+ INIT_LIST_HEAD(&tcp_ses->pending_mid_q);
+ mutex_init(&tcp_ses->_srv_mutex);
+ memcpy(tcp_ses->workstation_RFC1001_name,
+ ctx->source_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
+ memcpy(tcp_ses->server_RFC1001_name,
+ ctx->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
+ tcp_ses->session_estab = false;
+ tcp_ses->sequence_number = 0;
+ tcp_ses->channel_sequence_num = 0; /* only tracked for primary channel */
+ tcp_ses->reconnect_instance = 1;
+ tcp_ses->lstrp = jiffies;
+ tcp_ses->compress_algorithm = cpu_to_le16(ctx->compression);
+ spin_lock_init(&tcp_ses->req_lock);
+ spin_lock_init(&tcp_ses->srv_lock);
+ spin_lock_init(&tcp_ses->mid_lock);
+ INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
+ INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
+ INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
+ INIT_DELAYED_WORK(&tcp_ses->resolve, cifs_resolve_server);
+ INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
+ mutex_init(&tcp_ses->reconnect_mutex);
+#ifdef CONFIG_CIFS_DFS_UPCALL
+ mutex_init(&tcp_ses->refpath_lock);
+#endif
+ memcpy(&tcp_ses->srcaddr, &ctx->srcaddr,
+ sizeof(tcp_ses->srcaddr));
+ memcpy(&tcp_ses->dstaddr, &ctx->dstaddr,
+ sizeof(tcp_ses->dstaddr));
+ if (ctx->use_client_guid)
+ memcpy(tcp_ses->client_guid, ctx->client_guid,
+ SMB2_CLIENT_GUID_SIZE);
+ else
+ generate_random_uuid(tcp_ses->client_guid);
+ /*
+ * at this point we are the only ones with the pointer
+ * to the struct since the kernel thread not created yet
+ * no need to spinlock this init of tcpStatus or srv_count
+ */
+ tcp_ses->tcpStatus = CifsNew;
+ ++tcp_ses->srv_count;
+
+ if (ctx->echo_interval >= SMB_ECHO_INTERVAL_MIN &&
+ ctx->echo_interval <= SMB_ECHO_INTERVAL_MAX)
+ tcp_ses->echo_interval = ctx->echo_interval * HZ;
+ else
+ tcp_ses->echo_interval = SMB_ECHO_INTERVAL_DEFAULT * HZ;
+ if (tcp_ses->rdma) {
+#ifndef CONFIG_CIFS_SMB_DIRECT
+ cifs_dbg(VFS, "CONFIG_CIFS_SMB_DIRECT is not enabled\n");
+ rc = -ENOENT;
+ goto out_err_crypto_release;
+#endif
+ tcp_ses->smbd_conn = smbd_get_connection(
+ tcp_ses, (struct sockaddr *)&ctx->dstaddr);
+ if (tcp_ses->smbd_conn) {
+ cifs_dbg(VFS, "RDMA transport established\n");
+ rc = 0;
+ goto smbd_connected;
+ } else {
+ rc = -ENOENT;
+ goto out_err_crypto_release;
+ }
+ }
+ rc = ip_connect(tcp_ses);
+ if (rc < 0) {
+ cifs_dbg(VFS, "Error connecting to socket. Aborting operation.\n");
+ goto out_err_crypto_release;
+ }
+smbd_connected:
+ /*
+ * since we're in a cifs function already, we know that
+ * this will succeed. No need for try_module_get().
+ */
+ __module_get(THIS_MODULE);
+ tcp_ses->tsk = kthread_run(cifs_demultiplex_thread,
+ tcp_ses, "cifsd");
+ if (IS_ERR(tcp_ses->tsk)) {
+ rc = PTR_ERR(tcp_ses->tsk);
+ cifs_dbg(VFS, "error %d create cifsd thread\n", rc);
+ module_put(THIS_MODULE);
+ goto out_err_crypto_release;
+ }
+ tcp_ses->min_offload = ctx->min_offload;
+ /*
+ * at this point we are the only ones with the pointer
+ * to the struct since the kernel thread not created yet
+ * no need to spinlock this update of tcpStatus
+ */
+ spin_lock(&tcp_ses->srv_lock);
+ tcp_ses->tcpStatus = CifsNeedNegotiate;
+ spin_unlock(&tcp_ses->srv_lock);
+
+ if ((ctx->max_credits < 20) || (ctx->max_credits > 60000))
+ tcp_ses->max_credits = SMB2_MAX_CREDITS_AVAILABLE;
+ else
+ tcp_ses->max_credits = ctx->max_credits;
+
+ tcp_ses->nr_targets = 1;
+ tcp_ses->ignore_signature = ctx->ignore_signature;
+ /* thread spawned, put it on the list */
+ spin_lock(&cifs_tcp_ses_lock);
+ list_add(&tcp_ses->tcp_ses_list, &cifs_tcp_ses_list);
+ spin_unlock(&cifs_tcp_ses_lock);
+
+ /* queue echo request delayed work */
+ queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval);
+
+ /* queue dns resolution delayed work */
+ cifs_dbg(FYI, "%s: next dns resolution scheduled for %d seconds in the future\n",
+ __func__, SMB_DNS_RESOLVE_INTERVAL_DEFAULT);
+
+ queue_delayed_work(cifsiod_wq, &tcp_ses->resolve, (SMB_DNS_RESOLVE_INTERVAL_DEFAULT * HZ));
+
+ return tcp_ses;
+
+out_err_crypto_release:
+ cifs_crypto_secmech_release(tcp_ses);
+
+ put_net(cifs_net_ns(tcp_ses));
+
+out_err:
+ if (tcp_ses) {
+ if (CIFS_SERVER_IS_CHAN(tcp_ses))
+ cifs_put_tcp_session(tcp_ses->primary_server, false);
+ kfree(tcp_ses->hostname);
+ if (tcp_ses->ssocket)
+ sock_release(tcp_ses->ssocket);
+ kfree(tcp_ses);
+ }
+ return ERR_PTR(rc);
+}
+
+/* this function must be called with ses_lock and chan_lock held */
+static int match_session(struct cifs_ses *ses, struct smb3_fs_context *ctx)
+{
+ if (ctx->sectype != Unspecified &&
+ ctx->sectype != ses->sectype)
+ return 0;
+
+ /*
+ * If an existing session is limited to less channels than
+ * requested, it should not be reused
+ */
+ if (ses->chan_max < ctx->max_channels)
+ return 0;
+
+ switch (ses->sectype) {
+ case Kerberos:
+ if (!uid_eq(ctx->cred_uid, ses->cred_uid))
+ return 0;
+ break;
+ default:
+ /* NULL username means anonymous session */
+ if (ses->user_name == NULL) {
+ if (!ctx->nullauth)
+ return 0;
+ break;
+ }
+
+ /* anything else takes username/password */
+ if (strncmp(ses->user_name,
+ ctx->username ? ctx->username : "",
+ CIFS_MAX_USERNAME_LEN))
+ return 0;
+ if ((ctx->username && strlen(ctx->username) != 0) &&
+ ses->password != NULL &&
+ strncmp(ses->password,
+ ctx->password ? ctx->password : "",
+ CIFS_MAX_PASSWORD_LEN))
+ return 0;
+ }
+ return 1;
+}
+
+/**
+ * cifs_setup_ipc - helper to setup the IPC tcon for the session
+ * @ses: smb session to issue the request on
+ * @ctx: the superblock configuration context to use for building the
+ * new tree connection for the IPC (interprocess communication RPC)
+ *
+ * A new IPC connection is made and stored in the session
+ * tcon_ipc. The IPC tcon has the same lifetime as the session.
+ */
+static int
+cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
+{
+ int rc = 0, xid;
+ struct cifs_tcon *tcon;
+ char unc[SERVER_NAME_LENGTH + sizeof("//x/IPC$")] = {0};
+ bool seal = false;
+ struct TCP_Server_Info *server = ses->server;
+
+ /*
+ * If the mount request that resulted in the creation of the
+ * session requires encryption, force IPC to be encrypted too.
+ */
+ if (ctx->seal) {
+ if (server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION)
+ seal = true;
+ else {
+ cifs_server_dbg(VFS,
+ "IPC: server doesn't support encryption\n");
+ return -EOPNOTSUPP;
+ }
+ }
+
+ tcon = tconInfoAlloc();
+ if (tcon == NULL)
+ return -ENOMEM;
+
+ spin_lock(&server->srv_lock);
+ scnprintf(unc, sizeof(unc), "\\\\%s\\IPC$", server->hostname);
+ spin_unlock(&server->srv_lock);
+
+ xid = get_xid();
+ tcon->ses = ses;
+ tcon->ipc = true;
+ tcon->seal = seal;
+ rc = server->ops->tree_connect(xid, ses, unc, tcon, ctx->local_nls);
+ free_xid(xid);
+
+ if (rc) {
+ cifs_server_dbg(VFS, "failed to connect to IPC (rc=%d)\n", rc);
+ tconInfoFree(tcon);
+ goto out;
+ }
+
+ cifs_dbg(FYI, "IPC tcon rc=%d ipc tid=0x%x\n", rc, tcon->tid);
+
+ spin_lock(&tcon->tc_lock);
+ tcon->status = TID_GOOD;
+ spin_unlock(&tcon->tc_lock);
+ ses->tcon_ipc = tcon;
+out:
+ return rc;
+}
+
+/**
+ * cifs_free_ipc - helper to release the session IPC tcon
+ * @ses: smb session to unmount the IPC from
+ *
+ * Needs to be called everytime a session is destroyed.
+ *
+ * On session close, the IPC is closed and the server must release all tcons of the session.
+ * No need to send a tree disconnect here.
+ *
+ * Besides, it will make the server to not close durable and resilient files on session close, as
+ * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
+ */
+static int
+cifs_free_ipc(struct cifs_ses *ses)
+{
+ struct cifs_tcon *tcon = ses->tcon_ipc;
+
+ if (tcon == NULL)
+ return 0;
+
+ tconInfoFree(tcon);
+ ses->tcon_ipc = NULL;
+ return 0;
+}
+
+static struct cifs_ses *
+cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
+{
+ struct cifs_ses *ses;
+
+ spin_lock(&cifs_tcp_ses_lock);
+ list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
+ spin_lock(&ses->ses_lock);
+ if (ses->ses_status == SES_EXITING) {
+ spin_unlock(&ses->ses_lock);
+ continue;
+ }
+ spin_lock(&ses->chan_lock);
+ if (!match_session(ses, ctx)) {
+ spin_unlock(&ses->chan_lock);
+ spin_unlock(&ses->ses_lock);
+ continue;
+ }
+ spin_unlock(&ses->chan_lock);
+ spin_unlock(&ses->ses_lock);
+
+ ++ses->ses_count;
+ spin_unlock(&cifs_tcp_ses_lock);
+ return ses;
+ }
+ spin_unlock(&cifs_tcp_ses_lock);
+ return NULL;
+}
+
+void cifs_put_smb_ses(struct cifs_ses *ses)
+{
+ unsigned int rc, xid;
+ unsigned int chan_count;
+ struct TCP_Server_Info *server = ses->server;
+
+ spin_lock(&ses->ses_lock);
+ if (ses->ses_status == SES_EXITING) {
+ spin_unlock(&ses->ses_lock);
+ return;
+ }
+ spin_unlock(&ses->ses_lock);
+
+ cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
+ cifs_dbg(FYI,
+ "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->tree_name : "NONE");
+
+ spin_lock(&cifs_tcp_ses_lock);
+ if (--ses->ses_count > 0) {
+ spin_unlock(&cifs_tcp_ses_lock);
+ return;
+ }
+ spin_unlock(&cifs_tcp_ses_lock);
+
+ /* ses_count can never go negative */
+ WARN_ON(ses->ses_count < 0);
+
+ if (ses->ses_status == SES_GOOD)
+ ses->ses_status = SES_EXITING;
+
+ cifs_free_ipc(ses);
+
+ if (ses->ses_status == SES_EXITING && server->ops->logoff) {
+ xid = get_xid();
+ rc = server->ops->logoff(xid, ses);
+ if (rc)
+ cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
+ __func__, rc);
+ _free_xid(xid);
+ }
+
+ spin_lock(&cifs_tcp_ses_lock);
+ list_del_init(&ses->smb_ses_list);
+ spin_unlock(&cifs_tcp_ses_lock);
+
+ chan_count = ses->chan_count;
+
+ /* close any extra channels */
+ if (chan_count > 1) {
+ int i;
+
+ for (i = 1; i < chan_count; i++) {
+ if (ses->chans[i].iface) {
+ kref_put(&ses->chans[i].iface->refcount, release_iface);
+ ses->chans[i].iface = NULL;
+ }
+ cifs_put_tcp_session(ses->chans[i].server, 0);
+ ses->chans[i].server = NULL;
+ }
+ }
+
+ /* we now account for primary channel in iface->refcount */
+ if (ses->chans[0].iface) {
+ kref_put(&ses->chans[0].iface->refcount, release_iface);
+ ses->chans[0].server = NULL;
+ }
+
+ sesInfoFree(ses);
+ cifs_put_tcp_session(server, 0);
+}
+
+#ifdef CONFIG_KEYS
+
+/* strlen("cifs:a:") + CIFS_MAX_DOMAINNAME_LEN + 1 */
+#define CIFSCREDS_DESC_SIZE (7 + CIFS_MAX_DOMAINNAME_LEN + 1)
+
+/* Populate username and pw fields from keyring if possible */
+static int
+cifs_set_cifscreds(struct smb3_fs_context *ctx, struct cifs_ses *ses)
+{
+ int rc = 0;
+ int is_domain = 0;
+ const char *delim, *payload;
+ char *desc;
+ ssize_t len;
+ struct key *key;
+ struct TCP_Server_Info *server = ses->server;
+ struct sockaddr_in *sa;
+ struct sockaddr_in6 *sa6;
+ const struct user_key_payload *upayload;
+
+ desc = kmalloc(CIFSCREDS_DESC_SIZE, GFP_KERNEL);
+ if (!desc)
+ return -ENOMEM;
+
+ /* try to find an address key first */
+ switch (server->dstaddr.ss_family) {
+ case AF_INET:
+ sa = (struct sockaddr_in *)&server->dstaddr;
+ sprintf(desc, "cifs:a:%pI4", &sa->sin_addr.s_addr);
+ break;
+ case AF_INET6:
+ sa6 = (struct sockaddr_in6 *)&server->dstaddr;
+ sprintf(desc, "cifs:a:%pI6c", &sa6->sin6_addr.s6_addr);
+ break;
+ default:
+ cifs_dbg(FYI, "Bad ss_family (%hu)\n",
+ server->dstaddr.ss_family);
+ rc = -EINVAL;
+ goto out_err;
+ }
+
+ cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
+ key = request_key(&key_type_logon, desc, "");
+ if (IS_ERR(key)) {
+ if (!ses->domainName) {
+ cifs_dbg(FYI, "domainName is NULL\n");
+ rc = PTR_ERR(key);
+ goto out_err;
+ }
+
+ /* didn't work, try to find a domain key */
+ sprintf(desc, "cifs:d:%s", ses->domainName);
+ cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
+ key = request_key(&key_type_logon, desc, "");
+ if (IS_ERR(key)) {
+ rc = PTR_ERR(key);
+ goto out_err;
+ }
+ is_domain = 1;
+ }
+
+ down_read(&key->sem);
+ upayload = user_key_payload_locked(key);
+ if (IS_ERR_OR_NULL(upayload)) {
+ rc = upayload ? PTR_ERR(upayload) : -EINVAL;
+ goto out_key_put;
+ }
+
+ /* find first : in payload */
+ payload = upayload->data;
+ delim = strnchr(payload, upayload->datalen, ':');
+ cifs_dbg(FYI, "payload=%s\n", payload);
+ if (!delim) {
+ cifs_dbg(FYI, "Unable to find ':' in payload (datalen=%d)\n",
+ upayload->datalen);
+ rc = -EINVAL;
+ goto out_key_put;
+ }
+
+ len = delim - payload;
+ if (len > CIFS_MAX_USERNAME_LEN || len <= 0) {
+ cifs_dbg(FYI, "Bad value from username search (len=%zd)\n",
+ len);
+ rc = -EINVAL;
+ goto out_key_put;
+ }
+
+ ctx->username = kstrndup(payload, len, GFP_KERNEL);
+ if (!ctx->username) {
+ cifs_dbg(FYI, "Unable to allocate %zd bytes for username\n",
+ len);
+ rc = -ENOMEM;
+ goto out_key_put;
+ }
+ cifs_dbg(FYI, "%s: username=%s\n", __func__, ctx->username);
+
+ len = key->datalen - (len + 1);
+ if (len > CIFS_MAX_PASSWORD_LEN || len <= 0) {
+ cifs_dbg(FYI, "Bad len for password search (len=%zd)\n", len);
+ rc = -EINVAL;
+ kfree(ctx->username);
+ ctx->username = NULL;
+ goto out_key_put;
+ }
+
+ ++delim;
+ ctx->password = kstrndup(delim, len, GFP_KERNEL);
+ if (!ctx->password) {
+ cifs_dbg(FYI, "Unable to allocate %zd bytes for password\n",
+ len);
+ rc = -ENOMEM;
+ kfree(ctx->username);
+ ctx->username = NULL;
+ goto out_key_put;
+ }
+
+ /*
+ * If we have a domain key then we must set the domainName in the
+ * for the request.
+ */
+ if (is_domain && ses->domainName) {
+ ctx->domainname = kstrdup(ses->domainName, GFP_KERNEL);
+ if (!ctx->domainname) {
+ cifs_dbg(FYI, "Unable to allocate %zd bytes for domain\n",
+ len);
+ rc = -ENOMEM;
+ kfree(ctx->username);
+ ctx->username = NULL;
+ kfree_sensitive(ctx->password);
+ ctx->password = NULL;
+ goto out_key_put;
+ }
+ }
+
+ strscpy(ctx->workstation_name, ses->workstation_name, sizeof(ctx->workstation_name));
+
+out_key_put:
+ up_read(&key->sem);
+ key_put(key);
+out_err:
+ kfree(desc);
+ cifs_dbg(FYI, "%s: returning %d\n", __func__, rc);
+ return rc;
+}
+#else /* ! CONFIG_KEYS */
+static inline int
+cifs_set_cifscreds(struct smb3_fs_context *ctx __attribute__((unused)),
+ struct cifs_ses *ses __attribute__((unused)))
+{
+ return -ENOSYS;
+}
+#endif /* CONFIG_KEYS */
+
+/**
+ * cifs_get_smb_ses - get a session matching @ctx data from @server
+ * @server: server to setup the session to
+ * @ctx: superblock configuration context to use to setup the session
+ *
+ * This function assumes it is being called from cifs_mount() where we
+ * already got a server reference (server refcount +1). See
+ * cifs_get_tcon() for refcount explanations.
+ */
+struct cifs_ses *
+cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
+{
+ int rc = 0;
+ unsigned int xid;
+ struct cifs_ses *ses;
+ struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
+ struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
+
+ xid = get_xid();
+
+ ses = cifs_find_smb_ses(server, ctx);
+ if (ses) {
+ cifs_dbg(FYI, "Existing smb sess found (status=%d)\n",
+ ses->ses_status);
+
+ spin_lock(&ses->chan_lock);
+ if (cifs_chan_needs_reconnect(ses, server)) {
+ spin_unlock(&ses->chan_lock);
+ cifs_dbg(FYI, "Session needs reconnect\n");
+
+ mutex_lock(&ses->session_mutex);
+ rc = cifs_negotiate_protocol(xid, ses, server);
+ if (rc) {
+ mutex_unlock(&ses->session_mutex);
+ /* problem -- put our ses reference */
+ cifs_put_smb_ses(ses);
+ free_xid(xid);
+ return ERR_PTR(rc);
+ }
+
+ rc = cifs_setup_session(xid, ses, server,
+ ctx->local_nls);
+ if (rc) {
+ mutex_unlock(&ses->session_mutex);
+ /* problem -- put our reference */
+ cifs_put_smb_ses(ses);
+ free_xid(xid);
+ return ERR_PTR(rc);
+ }
+ mutex_unlock(&ses->session_mutex);
+
+ spin_lock(&ses->chan_lock);
+ }
+ spin_unlock(&ses->chan_lock);
+
+ /* existing SMB ses has a server reference already */
+ cifs_put_tcp_session(server, 0);
+ free_xid(xid);
+ return ses;
+ }
+
+ rc = -ENOMEM;
+
+ cifs_dbg(FYI, "Existing smb sess not found\n");
+ ses = sesInfoAlloc();
+ if (ses == NULL)
+ goto get_ses_fail;
+
+ /* new SMB session uses our server ref */
+ ses->server = server;
+ if (server->dstaddr.ss_family == AF_INET6)
+ sprintf(ses->ip_addr, "%pI6", &addr6->sin6_addr);
+ else
+ sprintf(ses->ip_addr, "%pI4", &addr->sin_addr);
+
+ if (ctx->username) {
+ ses->user_name = kstrdup(ctx->username, GFP_KERNEL);
+ if (!ses->user_name)
+ goto get_ses_fail;
+ }
+
+ /* ctx->password freed at unmount */
+ if (ctx->password) {
+ ses->password = kstrdup(ctx->password, GFP_KERNEL);
+ if (!ses->password)
+ goto get_ses_fail;
+ }
+ if (ctx->domainname) {
+ ses->domainName = kstrdup(ctx->domainname, GFP_KERNEL);
+ if (!ses->domainName)
+ goto get_ses_fail;
+ }
+
+ strscpy(ses->workstation_name, ctx->workstation_name, sizeof(ses->workstation_name));
+
+ if (ctx->domainauto)
+ ses->domainAuto = ctx->domainauto;
+ ses->cred_uid = ctx->cred_uid;
+ ses->linux_uid = ctx->linux_uid;
+
+ ses->sectype = ctx->sectype;
+ ses->sign = ctx->sign;
+
+ /* add server as first channel */
+ spin_lock(&ses->chan_lock);
+ ses->chans[0].server = server;
+ ses->chan_count = 1;
+ ses->chan_max = ctx->multichannel ? ctx->max_channels:1;
+ ses->chans_need_reconnect = 1;
+ spin_unlock(&ses->chan_lock);
+
+ mutex_lock(&ses->session_mutex);
+ rc = cifs_negotiate_protocol(xid, ses, server);
+ if (!rc)
+ rc = cifs_setup_session(xid, ses, server, ctx->local_nls);
+ mutex_unlock(&ses->session_mutex);
+
+ /* each channel uses a different signing key */
+ spin_lock(&ses->chan_lock);
+ memcpy(ses->chans[0].signkey, ses->smb3signingkey,
+ sizeof(ses->smb3signingkey));
+ spin_unlock(&ses->chan_lock);
+
+ if (rc)
+ goto get_ses_fail;
+
+ /*
+ * success, put it on the list and add it as first channel
+ * note: the session becomes active soon after this. So you'll
+ * need to lock before changing something in the session.
+ */
+ spin_lock(&cifs_tcp_ses_lock);
+ list_add(&ses->smb_ses_list, &server->smb_ses_list);
+ spin_unlock(&cifs_tcp_ses_lock);
+
+ cifs_setup_ipc(ses, ctx);
+
+ free_xid(xid);
+
+ return ses;
+
+get_ses_fail:
+ sesInfoFree(ses);
+ free_xid(xid);
+ return ERR_PTR(rc);
+}
+
+/* this function must be called with tc_lock held */
+static int match_tcon(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
+{
+ if (tcon->status == TID_EXITING)
+ return 0;
+ if (strncmp(tcon->tree_name, ctx->UNC, MAX_TREE_SIZE))
+ return 0;
+ if (tcon->seal != ctx->seal)
+ return 0;
+ if (tcon->snapshot_time != ctx->snapshot_time)
+ return 0;
+ if (tcon->handle_timeout != ctx->handle_timeout)
+ return 0;
+ if (tcon->no_lease != ctx->no_lease)
+ return 0;
+ if (tcon->nodelete != ctx->nodelete)
+ return 0;
+ return 1;
+}
+
+static struct cifs_tcon *
+cifs_find_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
+{
+ struct cifs_tcon *tcon;
+
+ spin_lock(&cifs_tcp_ses_lock);
+ list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
+ spin_lock(&tcon->tc_lock);
+ if (!match_tcon(tcon, ctx)) {
+ spin_unlock(&tcon->tc_lock);
+ continue;
+ }
+ ++tcon->tc_count;
+ spin_unlock(&tcon->tc_lock);
+ spin_unlock(&cifs_tcp_ses_lock);
+ return tcon;
+ }
+ spin_unlock(&cifs_tcp_ses_lock);
+ return NULL;
+}
+
+void
+cifs_put_tcon(struct cifs_tcon *tcon)
+{
+ unsigned int xid;
+ struct cifs_ses *ses;
+
+ /*
+ * IPC tcon share the lifetime of their session and are
+ * destroyed in the session put function
+ */
+ if (tcon == NULL || tcon->ipc)
+ return;
+
+ ses = tcon->ses;
+ cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
+ spin_lock(&cifs_tcp_ses_lock);
+ spin_lock(&tcon->tc_lock);
+ if (--tcon->tc_count > 0) {
+ spin_unlock(&tcon->tc_lock);
+ spin_unlock(&cifs_tcp_ses_lock);
+ return;
+ }
+
+ /* tc_count can never go negative */
+ WARN_ON(tcon->tc_count < 0);
+
+ list_del_init(&tcon->tcon_list);
+ tcon->status = TID_EXITING;
+ spin_unlock(&tcon->tc_lock);
+ spin_unlock(&cifs_tcp_ses_lock);
+
+ /* cancel polling of interfaces */
+ cancel_delayed_work_sync(&tcon->query_interfaces);
+
+ if (tcon->use_witness) {
+ int rc;
+
+ rc = cifs_swn_unregister(tcon);
+ if (rc < 0) {
+ cifs_dbg(VFS, "%s: Failed to unregister for witness notifications: %d\n",
+ __func__, rc);
+ }
+ }
+
+ xid = get_xid();
+ if (ses->server->ops->tree_disconnect)
+ ses->server->ops->tree_disconnect(xid, tcon);
+ _free_xid(xid);
+
+ cifs_fscache_release_super_cookie(tcon);
+ tconInfoFree(tcon);
+ cifs_put_smb_ses(ses);
+}
+
+/**
+ * cifs_get_tcon - get a tcon matching @ctx data from @ses
+ * @ses: smb session to issue the request on
+ * @ctx: the superblock configuration context to use for building the
+ *
+ * - tcon refcount is the number of mount points using the tcon.
+ * - ses refcount is the number of tcon using the session.
+ *
+ * 1. This function assumes it is being called from cifs_mount() where
+ * we already got a session reference (ses refcount +1).
+ *
+ * 2. Since we're in the context of adding a mount point, the end
+ * result should be either:
+ *
+ * a) a new tcon already allocated with refcount=1 (1 mount point) and
+ * its session refcount incremented (1 new tcon). This +1 was
+ * already done in (1).
+ *
+ * b) an existing tcon with refcount+1 (add a mount point to it) and
+ * identical ses refcount (no new tcon). Because of (1) we need to
+ * decrement the ses refcount.
+ */
+static struct cifs_tcon *
+cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
+{
+ int rc, xid;
+ struct cifs_tcon *tcon;
+
+ tcon = cifs_find_tcon(ses, ctx);
+ if (tcon) {
+ /*
+ * tcon has refcount already incremented but we need to
+ * decrement extra ses reference gotten by caller (case b)
+ */
+ cifs_dbg(FYI, "Found match on UNC path\n");
+ cifs_put_smb_ses(ses);
+ return tcon;
+ }
+
+ if (!ses->server->ops->tree_connect) {
+ rc = -ENOSYS;
+ goto out_fail;
+ }
+
+ tcon = tconInfoAlloc();
+ if (tcon == NULL) {
+ rc = -ENOMEM;
+ goto out_fail;
+ }
+
+ if (ctx->snapshot_time) {
+ if (ses->server->vals->protocol_id == 0) {
+ cifs_dbg(VFS,
+ "Use SMB2 or later for snapshot mount option\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ } else
+ tcon->snapshot_time = ctx->snapshot_time;
+ }
+
+ if (ctx->handle_timeout) {
+ if (ses->server->vals->protocol_id == 0) {
+ cifs_dbg(VFS,
+ "Use SMB2.1 or later for handle timeout option\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ } else
+ tcon->handle_timeout = ctx->handle_timeout;
+ }
+
+ tcon->ses = ses;
+ if (ctx->password) {
+ tcon->password = kstrdup(ctx->password, GFP_KERNEL);
+ if (!tcon->password) {
+ rc = -ENOMEM;
+ goto out_fail;
+ }
+ }
+
+ if (ctx->seal) {
+ if (ses->server->vals->protocol_id == 0) {
+ cifs_dbg(VFS,
+ "SMB3 or later required for encryption\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ } else if (tcon->ses->server->capabilities &
+ SMB2_GLOBAL_CAP_ENCRYPTION)
+ tcon->seal = true;
+ else {
+ cifs_dbg(VFS, "Encryption is not supported on share\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ }
+ }
+
+ if (ctx->linux_ext) {
+ if (ses->server->posix_ext_supported) {
+ tcon->posix_extensions = true;
+ pr_warn_once("SMB3.11 POSIX Extensions are experimental\n");
+ } else if ((ses->server->vals->protocol_id == SMB311_PROT_ID) ||
+ (strcmp(ses->server->vals->version_string,
+ SMB3ANY_VERSION_STRING) == 0) ||
+ (strcmp(ses->server->vals->version_string,
+ SMBDEFAULT_VERSION_STRING) == 0)) {
+ cifs_dbg(VFS, "Server does not support mounting with posix SMB3.11 extensions\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ } else {
+ cifs_dbg(VFS, "Check vers= mount option. SMB3.11 "
+ "disabled but required for POSIX extensions\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ }
+ }
+
+ xid = get_xid();
+ rc = ses->server->ops->tree_connect(xid, ses, ctx->UNC, tcon,
+ ctx->local_nls);
+ free_xid(xid);
+ cifs_dbg(FYI, "Tcon rc = %d\n", rc);
+ if (rc)
+ goto out_fail;
+
+ tcon->use_persistent = false;
+ /* check if SMB2 or later, CIFS does not support persistent handles */
+ if (ctx->persistent) {
+ if (ses->server->vals->protocol_id == 0) {
+ cifs_dbg(VFS,
+ "SMB3 or later required for persistent handles\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ } else if (ses->server->capabilities &
+ SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
+ tcon->use_persistent = true;
+ else /* persistent handles requested but not supported */ {
+ cifs_dbg(VFS,
+ "Persistent handles not supported on share\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ }
+ } else if ((tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
+ && (ses->server->capabilities & SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
+ && (ctx->nopersistent == false)) {
+ cifs_dbg(FYI, "enabling persistent handles\n");
+ tcon->use_persistent = true;
+ } else if (ctx->resilient) {
+ if (ses->server->vals->protocol_id == 0) {
+ cifs_dbg(VFS,
+ "SMB2.1 or later required for resilient handles\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ }
+ tcon->use_resilient = true;
+ }
+
+ tcon->use_witness = false;
+ if (IS_ENABLED(CONFIG_CIFS_SWN_UPCALL) && ctx->witness) {
+ if (ses->server->vals->protocol_id >= SMB30_PROT_ID) {
+ if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER) {
+ /*
+ * Set witness in use flag in first place
+ * to retry registration in the echo task
+ */
+ tcon->use_witness = true;
+ /* And try to register immediately */
+ rc = cifs_swn_register(tcon);
+ if (rc < 0) {
+ cifs_dbg(VFS, "Failed to register for witness notifications: %d\n", rc);
+ goto out_fail;
+ }
+ } else {
+ /* TODO: try to extend for non-cluster uses (eg multichannel) */
+ cifs_dbg(VFS, "witness requested on mount but no CLUSTER capability on share\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ }
+ } else {
+ cifs_dbg(VFS, "SMB3 or later required for witness option\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ }
+ }
+
+ /* If the user really knows what they are doing they can override */
+ if (tcon->share_flags & SMB2_SHAREFLAG_NO_CACHING) {
+ if (ctx->cache_ro)
+ cifs_dbg(VFS, "cache=ro requested on mount but NO_CACHING flag set on share\n");
+ else if (ctx->cache_rw)
+ cifs_dbg(VFS, "cache=singleclient requested on mount but NO_CACHING flag set on share\n");
+ }
+
+ if (ctx->no_lease) {
+ if (ses->server->vals->protocol_id == 0) {
+ cifs_dbg(VFS,
+ "SMB2 or later required for nolease option\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ } else
+ tcon->no_lease = ctx->no_lease;
+ }
+
+ /*
+ * We can have only one retry value for a connection to a share so for
+ * resources mounted more than once to the same server share the last
+ * value passed in for the retry flag is used.
+ */
+ tcon->retry = ctx->retry;
+ tcon->nocase = ctx->nocase;
+ tcon->broken_sparse_sup = ctx->no_sparse;
+ if (ses->server->capabilities & SMB2_GLOBAL_CAP_DIRECTORY_LEASING)
+ tcon->nohandlecache = ctx->nohandlecache;
+ else
+ tcon->nohandlecache = true;
+ tcon->nodelete = ctx->nodelete;
+ tcon->local_lease = ctx->local_lease;
+ INIT_LIST_HEAD(&tcon->pending_opens);
+ tcon->status = TID_GOOD;
+
+ INIT_DELAYED_WORK(&tcon->query_interfaces,
+ smb2_query_server_interfaces);
+ if (ses->server->dialect >= SMB30_PROT_ID &&
+ (ses->server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
+ /* schedule query interfaces poll */
+ queue_delayed_work(cifsiod_wq, &tcon->query_interfaces,
+ (SMB_INTERFACE_POLL_INTERVAL * HZ));
+ }
+
+ spin_lock(&cifs_tcp_ses_lock);
+ list_add(&tcon->tcon_list, &ses->tcon_list);
+ spin_unlock(&cifs_tcp_ses_lock);
+
+ return tcon;
+
+out_fail:
+ tconInfoFree(tcon);
+ return ERR_PTR(rc);
+}
+
+void
+cifs_put_tlink(struct tcon_link *tlink)
+{
+ if (!tlink || IS_ERR(tlink))
+ return;
+
+ if (!atomic_dec_and_test(&tlink->tl_count) ||
+ test_bit(TCON_LINK_IN_TREE, &tlink->tl_flags)) {
+ tlink->tl_time = jiffies;
+ return;
+ }
+
+ if (!IS_ERR(tlink_tcon(tlink)))
+ cifs_put_tcon(tlink_tcon(tlink));
+ kfree(tlink);
+ return;
+}
+
+static int
+compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data)
+{
+ struct cifs_sb_info *old = CIFS_SB(sb);
+ struct cifs_sb_info *new = mnt_data->cifs_sb;
+ unsigned int oldflags = old->mnt_cifs_flags & CIFS_MOUNT_MASK;
+ unsigned int newflags = new->mnt_cifs_flags & CIFS_MOUNT_MASK;
+
+ if ((sb->s_flags & CIFS_MS_MASK) != (mnt_data->flags & CIFS_MS_MASK))
+ return 0;
+
+ if (old->mnt_cifs_serverino_autodisabled)
+ newflags &= ~CIFS_MOUNT_SERVER_INUM;
+
+ if (oldflags != newflags)
+ return 0;
+
+ /*
+ * We want to share sb only if we don't specify an r/wsize or
+ * specified r/wsize is greater than or equal to existing one.
+ */
+ if (new->ctx->wsize && new->ctx->wsize < old->ctx->wsize)
+ return 0;
+
+ if (new->ctx->rsize && new->ctx->rsize < old->ctx->rsize)
+ return 0;
+
+ if (!uid_eq(old->ctx->linux_uid, new->ctx->linux_uid) ||
+ !gid_eq(old->ctx->linux_gid, new->ctx->linux_gid))
+ return 0;
+
+ if (old->ctx->file_mode != new->ctx->file_mode ||
+ old->ctx->dir_mode != new->ctx->dir_mode)
+ return 0;
+
+ if (strcmp(old->local_nls->charset, new->local_nls->charset))
+ return 0;
+
+ if (old->ctx->acregmax != new->ctx->acregmax)
+ return 0;
+ if (old->ctx->acdirmax != new->ctx->acdirmax)
+ return 0;
+ if (old->ctx->closetimeo != new->ctx->closetimeo)
+ return 0;
+
+ return 1;
+}
+
+static int
+match_prepath(struct super_block *sb, struct cifs_mnt_data *mnt_data)
+{
+ struct cifs_sb_info *old = CIFS_SB(sb);
+ struct cifs_sb_info *new = mnt_data->cifs_sb;
+ bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
+ old->prepath;
+ bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
+ new->prepath;
+
+ if (old_set && new_set && !strcmp(new->prepath, old->prepath))
+ return 1;
+ else if (!old_set && !new_set)
+ return 1;
+
+ return 0;
+}
+
+int
+cifs_match_super(struct super_block *sb, void *data)
+{
+ struct cifs_mnt_data *mnt_data = data;
+ struct smb3_fs_context *ctx;
+ struct cifs_sb_info *cifs_sb;
+ struct TCP_Server_Info *tcp_srv;
+ struct cifs_ses *ses;
+ struct cifs_tcon *tcon;
+ struct tcon_link *tlink;
+ int rc = 0;
+
+ spin_lock(&cifs_tcp_ses_lock);
+ cifs_sb = CIFS_SB(sb);
+
+ /* We do not want to use a superblock that has been shutdown */
+ if (CIFS_MOUNT_SHUTDOWN & cifs_sb->mnt_cifs_flags) {
+ spin_unlock(&cifs_tcp_ses_lock);
+ return 0;
+ }
+
+ tlink = cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
+ if (tlink == NULL) {
+ /* can not match superblock if tlink were ever null */
+ spin_unlock(&cifs_tcp_ses_lock);
+ return 0;
+ }
+ tcon = tlink_tcon(tlink);
+ ses = tcon->ses;
+ tcp_srv = ses->server;
+
+ ctx = mnt_data->ctx;
+
+ spin_lock(&tcp_srv->srv_lock);
+ spin_lock(&ses->ses_lock);
+ spin_lock(&ses->chan_lock);
+ spin_lock(&tcon->tc_lock);
+ if (!match_server(tcp_srv, ctx) ||
+ !match_session(ses, ctx) ||
+ !match_tcon(tcon, ctx) ||
+ !match_prepath(sb, mnt_data)) {
+ rc = 0;
+ goto out;
+ }
+
+ rc = compare_mount_options(sb, mnt_data);
+out:
+ spin_unlock(&tcon->tc_lock);
+ spin_unlock(&ses->chan_lock);
+ spin_unlock(&ses->ses_lock);
+ spin_unlock(&tcp_srv->srv_lock);
+
+ spin_unlock(&cifs_tcp_ses_lock);
+ cifs_put_tlink(tlink);
+ return rc;
+}
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+static struct lock_class_key cifs_key[2];
+static struct lock_class_key cifs_slock_key[2];
+
+static inline void
+cifs_reclassify_socket4(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+ BUG_ON(!sock_allow_reclassification(sk));
+ sock_lock_init_class_and_name(sk, "slock-AF_INET-CIFS",
+ &cifs_slock_key[0], "sk_lock-AF_INET-CIFS", &cifs_key[0]);
+}
+
+static inline void
+cifs_reclassify_socket6(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+ BUG_ON(!sock_allow_reclassification(sk));
+ sock_lock_init_class_and_name(sk, "slock-AF_INET6-CIFS",
+ &cifs_slock_key[1], "sk_lock-AF_INET6-CIFS", &cifs_key[1]);
+}
+#else
+static inline void
+cifs_reclassify_socket4(struct socket *sock)
+{
+}
+
+static inline void
+cifs_reclassify_socket6(struct socket *sock)
+{
+}
+#endif
+
+/* See RFC1001 section 14 on representation of Netbios names */
+static void rfc1002mangle(char *target, char *source, unsigned int length)
+{
+ unsigned int i, j;
+
+ for (i = 0, j = 0; i < (length); i++) {
+ /* mask a nibble at a time and encode */
+ target[j] = 'A' + (0x0F & (source[i] >> 4));
+ target[j+1] = 'A' + (0x0F & source[i]);
+ j += 2;
+ }
+
+}
+
+static int
+bind_socket(struct TCP_Server_Info *server)
+{
+ int rc = 0;
+ if (server->srcaddr.ss_family != AF_UNSPEC) {
+ /* Bind to the specified local IP address */
+ struct socket *socket = server->ssocket;
+ rc = kernel_bind(socket,
+ (struct sockaddr *) &server->srcaddr,
+ sizeof(server->srcaddr));
+ if (rc < 0) {
+ struct sockaddr_in *saddr4;
+ struct sockaddr_in6 *saddr6;
+ saddr4 = (struct sockaddr_in *)&server->srcaddr;
+ saddr6 = (struct sockaddr_in6 *)&server->srcaddr;
+ if (saddr6->sin6_family == AF_INET6)
+ cifs_server_dbg(VFS, "Failed to bind to: %pI6c, error: %d\n",
+ &saddr6->sin6_addr, rc);
+ else
+ cifs_server_dbg(VFS, "Failed to bind to: %pI4, error: %d\n",
+ &saddr4->sin_addr.s_addr, rc);
+ }
+ }
+ return rc;
+}
+
+static int
+ip_rfc1001_connect(struct TCP_Server_Info *server)
+{
+ int rc = 0;
+ /*
+ * some servers require RFC1001 sessinit before sending
+ * negprot - BB check reconnection in case where second
+ * sessinit is sent but no second negprot
+ */
+ struct rfc1002_session_packet req = {};
+ struct smb_hdr *smb_buf = (struct smb_hdr *)&req;
+ unsigned int len;
+
+ req.trailer.session_req.called_len = sizeof(req.trailer.session_req.called_name);
+
+ if (server->server_RFC1001_name[0] != 0)
+ rfc1002mangle(req.trailer.session_req.called_name,
+ server->server_RFC1001_name,
+ RFC1001_NAME_LEN_WITH_NULL);
+ else
+ rfc1002mangle(req.trailer.session_req.called_name,
+ DEFAULT_CIFS_CALLED_NAME,
+ RFC1001_NAME_LEN_WITH_NULL);
+
+ req.trailer.session_req.calling_len = sizeof(req.trailer.session_req.calling_name);
+
+ /* calling name ends in null (byte 16) from old smb convention */
+ if (server->workstation_RFC1001_name[0] != 0)
+ rfc1002mangle(req.trailer.session_req.calling_name,
+ server->workstation_RFC1001_name,
+ RFC1001_NAME_LEN_WITH_NULL);
+ else
+ rfc1002mangle(req.trailer.session_req.calling_name,
+ "LINUX_CIFS_CLNT",
+ RFC1001_NAME_LEN_WITH_NULL);
+
+ /*
+ * As per rfc1002, @len must be the number of bytes that follows the
+ * length field of a rfc1002 session request payload.
+ */
+ len = sizeof(req) - offsetof(struct rfc1002_session_packet, trailer.session_req);
+
+ smb_buf->smb_buf_length = cpu_to_be32((RFC1002_SESSION_REQUEST << 24) | len);
+ rc = smb_send(server, smb_buf, len);
+ /*
+ * RFC1001 layer in at least one server requires very short break before
+ * negprot presumably because not expecting negprot to follow so fast.
+ * This is a simple solution that works without complicating the code
+ * and causes no significant slowing down on mount for everyone else
+ */
+ usleep_range(1000, 2000);
+
+ return rc;
+}
+
+static int
+generic_ip_connect(struct TCP_Server_Info *server)
+{
+ int rc = 0;
+ __be16 sport;
+ int slen, sfamily;
+ struct socket *socket = server->ssocket;
+ struct sockaddr *saddr;
+
+ saddr = (struct sockaddr *) &server->dstaddr;
+
+ if (server->dstaddr.ss_family == AF_INET6) {
+ struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&server->dstaddr;
+
+ sport = ipv6->sin6_port;
+ slen = sizeof(struct sockaddr_in6);
+ sfamily = AF_INET6;
+ cifs_dbg(FYI, "%s: connecting to [%pI6]:%d\n", __func__, &ipv6->sin6_addr,
+ ntohs(sport));
+ } else {
+ struct sockaddr_in *ipv4 = (struct sockaddr_in *)&server->dstaddr;
+
+ sport = ipv4->sin_port;
+ slen = sizeof(struct sockaddr_in);
+ sfamily = AF_INET;
+ cifs_dbg(FYI, "%s: connecting to %pI4:%d\n", __func__, &ipv4->sin_addr,
+ ntohs(sport));
+ }
+
+ if (socket == NULL) {
+ rc = __sock_create(cifs_net_ns(server), sfamily, SOCK_STREAM,
+ IPPROTO_TCP, &socket, 1);
+ if (rc < 0) {
+ cifs_server_dbg(VFS, "Error %d creating socket\n", rc);
+ server->ssocket = NULL;
+ return rc;
+ }
+
+ /* BB other socket options to set KEEPALIVE, NODELAY? */
+ cifs_dbg(FYI, "Socket created\n");
+ server->ssocket = socket;
+ socket->sk->sk_allocation = GFP_NOFS;
+ if (sfamily == AF_INET6)
+ cifs_reclassify_socket6(socket);
+ else
+ cifs_reclassify_socket4(socket);
+ }
+
+ rc = bind_socket(server);
+ if (rc < 0)
+ return rc;
+
+ /*
+ * Eventually check for other socket options to change from
+ * the default. sock_setsockopt not used because it expects
+ * user space buffer
+ */
+ socket->sk->sk_rcvtimeo = 7 * HZ;
+ socket->sk->sk_sndtimeo = 5 * HZ;
+
+ /* make the bufsizes depend on wsize/rsize and max requests */
+ if (server->noautotune) {
+ if (socket->sk->sk_sndbuf < (200 * 1024))
+ socket->sk->sk_sndbuf = 200 * 1024;
+ if (socket->sk->sk_rcvbuf < (140 * 1024))
+ socket->sk->sk_rcvbuf = 140 * 1024;
+ }
+
+ if (server->tcp_nodelay)
+ tcp_sock_set_nodelay(socket->sk);
+
+ cifs_dbg(FYI, "sndbuf %d rcvbuf %d rcvtimeo 0x%lx\n",
+ socket->sk->sk_sndbuf,
+ socket->sk->sk_rcvbuf, socket->sk->sk_rcvtimeo);
+
+ rc = kernel_connect(socket, saddr, slen,
+ server->noblockcnt ? O_NONBLOCK : 0);
+ /*
+ * When mounting SMB root file systems, we do not want to block in
+ * connect. Otherwise bail out and then let cifs_reconnect() perform
+ * reconnect failover - if possible.
+ */
+ if (server->noblockcnt && rc == -EINPROGRESS)
+ rc = 0;
+ if (rc < 0) {
+ cifs_dbg(FYI, "Error %d connecting to server\n", rc);
+ trace_smb3_connect_err(server->hostname, server->conn_id, &server->dstaddr, rc);
+ sock_release(socket);
+ server->ssocket = NULL;
+ return rc;
+ }
+ trace_smb3_connect_done(server->hostname, server->conn_id, &server->dstaddr);
+ if (sport == htons(RFC1001_PORT))
+ rc = ip_rfc1001_connect(server);
+
+ return rc;
+}
+
+static int
+ip_connect(struct TCP_Server_Info *server)
+{
+ __be16 *sport;
+ struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
+ struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
+
+ if (server->dstaddr.ss_family == AF_INET6)
+ sport = &addr6->sin6_port;
+ else
+ sport = &addr->sin_port;
+
+ if (*sport == 0) {
+ int rc;
+
+ /* try with 445 port at first */
+ *sport = htons(CIFS_PORT);
+
+ rc = generic_ip_connect(server);
+ if (rc >= 0)
+ return rc;
+
+ /* if it failed, try with 139 port */
+ *sport = htons(RFC1001_PORT);
+ }
+
+ return generic_ip_connect(server);
+}
+
+#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
+void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
+ struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
+{
+ /*
+ * If we are reconnecting then should we check to see if
+ * any requested capabilities changed locally e.g. via
+ * remount but we can not do much about it here
+ * if they have (even if we could detect it by the following)
+ * Perhaps we could add a backpointer to array of sb from tcon
+ * or if we change to make all sb to same share the same
+ * sb as NFS - then we only have one backpointer to sb.
+ * What if we wanted to mount the server share twice once with
+ * and once without posixacls or posix paths?
+ */
+ __u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
+
+ if (ctx && ctx->no_linux_ext) {
+ tcon->fsUnixInfo.Capability = 0;
+ tcon->unix_ext = 0; /* Unix Extensions disabled */
+ cifs_dbg(FYI, "Linux protocol extensions disabled\n");
+ return;
+ } else if (ctx)
+ tcon->unix_ext = 1; /* Unix Extensions supported */
+
+ if (!tcon->unix_ext) {
+ cifs_dbg(FYI, "Unix extensions disabled so not set on reconnect\n");
+ return;
+ }
+
+ if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
+ __u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
+ cifs_dbg(FYI, "unix caps which server supports %lld\n", cap);
+ /*
+ * check for reconnect case in which we do not
+ * want to change the mount behavior if we can avoid it
+ */
+ if (ctx == NULL) {
+ /*
+ * turn off POSIX ACL and PATHNAMES if not set
+ * originally at mount time
+ */
+ if ((saved_cap & CIFS_UNIX_POSIX_ACL_CAP) == 0)
+ cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
+ if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
+ if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
+ cifs_dbg(VFS, "POSIXPATH support change\n");
+ cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
+ } else if ((cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
+ cifs_dbg(VFS, "possible reconnect error\n");
+ cifs_dbg(VFS, "server disabled POSIX path support\n");
+ }
+ }
+
+ if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
+ cifs_dbg(VFS, "per-share encryption not supported yet\n");
+
+ cap &= CIFS_UNIX_CAP_MASK;
+ if (ctx && ctx->no_psx_acl)
+ cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
+ else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
+ cifs_dbg(FYI, "negotiated posix acl support\n");
+ if (cifs_sb)
+ cifs_sb->mnt_cifs_flags |=
+ CIFS_MOUNT_POSIXACL;
+ }
+
+ if (ctx && ctx->posix_paths == 0)
+ cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
+ else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
+ cifs_dbg(FYI, "negotiate posix pathnames\n");
+ if (cifs_sb)
+ cifs_sb->mnt_cifs_flags |=
+ CIFS_MOUNT_POSIX_PATHS;
+ }
+
+ cifs_dbg(FYI, "Negotiate caps 0x%x\n", (int)cap);
+#ifdef CONFIG_CIFS_DEBUG2
+ if (cap & CIFS_UNIX_FCNTL_CAP)
+ cifs_dbg(FYI, "FCNTL cap\n");
+ if (cap & CIFS_UNIX_EXTATTR_CAP)
+ cifs_dbg(FYI, "EXTATTR cap\n");
+ if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
+ cifs_dbg(FYI, "POSIX path cap\n");
+ if (cap & CIFS_UNIX_XATTR_CAP)
+ cifs_dbg(FYI, "XATTR cap\n");
+ if (cap & CIFS_UNIX_POSIX_ACL_CAP)
+ cifs_dbg(FYI, "POSIX ACL cap\n");
+ if (cap & CIFS_UNIX_LARGE_READ_CAP)
+ cifs_dbg(FYI, "very large read cap\n");
+ if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
+ cifs_dbg(FYI, "very large write cap\n");
+ if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_CAP)
+ cifs_dbg(FYI, "transport encryption cap\n");
+ if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
+ cifs_dbg(FYI, "mandatory transport encryption cap\n");
+#endif /* CIFS_DEBUG2 */
+ if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
+ if (ctx == NULL)
+ cifs_dbg(FYI, "resetting capabilities failed\n");
+ else
+ cifs_dbg(VFS, "Negotiating Unix capabilities with the server failed. Consider mounting with the Unix Extensions disabled if problems are found by specifying the nounix mount option.\n");
+
+ }
+ }
+}
+#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
+
+int cifs_setup_cifs_sb(struct cifs_sb_info *cifs_sb)
+{
+ struct smb3_fs_context *ctx = cifs_sb->ctx;
+
+ INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
+
+ spin_lock_init(&cifs_sb->tlink_tree_lock);
+ cifs_sb->tlink_tree = RB_ROOT;
+
+ cifs_dbg(FYI, "file mode: %04ho dir mode: %04ho\n",
+ ctx->file_mode, ctx->dir_mode);
+
+ /* this is needed for ASCII cp to Unicode converts */
+ if (ctx->iocharset == NULL) {
+ /* load_nls_default cannot return null */
+ cifs_sb->local_nls = load_nls_default();
+ } else {
+ cifs_sb->local_nls = load_nls(ctx->iocharset);
+ if (cifs_sb->local_nls == NULL) {
+ cifs_dbg(VFS, "CIFS mount error: iocharset %s not found\n",
+ ctx->iocharset);
+ return -ELIBACC;
+ }
+ }
+ ctx->local_nls = cifs_sb->local_nls;
+
+ smb3_update_mnt_flags(cifs_sb);
+
+ if (ctx->direct_io)
+ cifs_dbg(FYI, "mounting share using direct i/o\n");
+ if (ctx->cache_ro) {
+ cifs_dbg(VFS, "mounting share with read only caching. Ensure that the share will not be modified while in use.\n");
+ cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RO_CACHE;
+ } else if (ctx->cache_rw) {
+ cifs_dbg(VFS, "mounting share in single client RW caching mode. Ensure that no other systems will be accessing the share.\n");
+ cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_RO_CACHE |
+ CIFS_MOUNT_RW_CACHE);
+ }
+
+ if ((ctx->cifs_acl) && (ctx->dynperm))
+ cifs_dbg(VFS, "mount option dynperm ignored if cifsacl mount option supported\n");
+
+ if (ctx->prepath) {
+ cifs_sb->prepath = kstrdup(ctx->prepath, GFP_KERNEL);
+ if (cifs_sb->prepath == NULL)
+ return -ENOMEM;
+ cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
+ }
+
+ return 0;
+}
+
+/* Release all succeed connections */
+static inline void mount_put_conns(struct mount_ctx *mnt_ctx)
+{
+ int rc = 0;
+
+ if (mnt_ctx->tcon)
+ cifs_put_tcon(mnt_ctx->tcon);
+ else if (mnt_ctx->ses)
+ cifs_put_smb_ses(mnt_ctx->ses);
+ else if (mnt_ctx->server)
+ cifs_put_tcp_session(mnt_ctx->server, 0);
+ mnt_ctx->cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_POSIX_PATHS;
+ free_xid(mnt_ctx->xid);
+}
+
+/* Get connections for tcp, ses and tcon */
+static int mount_get_conns(struct mount_ctx *mnt_ctx)
+{
+ int rc = 0;
+ struct TCP_Server_Info *server = NULL;
+ struct cifs_ses *ses = NULL;
+ struct cifs_tcon *tcon = NULL;
+ struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
+ struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
+ unsigned int xid;
+
+ xid = get_xid();
+
+ /* get a reference to a tcp session */
+ server = cifs_get_tcp_session(ctx, NULL);
+ if (IS_ERR(server)) {
+ rc = PTR_ERR(server);
+ server = NULL;
+ goto out;
+ }
+
+ /* get a reference to a SMB session */
+ ses = cifs_get_smb_ses(server, ctx);
+ if (IS_ERR(ses)) {
+ rc = PTR_ERR(ses);
+ ses = NULL;
+ goto out;
+ }
+
+ if ((ctx->persistent == true) && (!(ses->server->capabilities &
+ SMB2_GLOBAL_CAP_PERSISTENT_HANDLES))) {
+ cifs_server_dbg(VFS, "persistent handles not supported by server\n");
+ rc = -EOPNOTSUPP;
+ goto out;
+ }
+
+ /* search for existing tcon to this server share */
+ tcon = cifs_get_tcon(ses, ctx);
+ if (IS_ERR(tcon)) {
+ rc = PTR_ERR(tcon);
+ tcon = NULL;
+ goto out;
+ }
+
+ /* if new SMB3.11 POSIX extensions are supported do not remap / and \ */
+ if (tcon->posix_extensions)
+ cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_POSIX_PATHS;
+
+#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
+ /* tell server which Unix caps we support */
+ if (cap_unix(tcon->ses)) {
+ /*
+ * reset of caps checks mount to see if unix extensions disabled
+ * for just this mount.
+ */
+ reset_cifs_unix_caps(xid, tcon, cifs_sb, ctx);
+ spin_lock(&tcon->ses->server->srv_lock);
+ if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
+ (le64_to_cpu(tcon->fsUnixInfo.Capability) &
+ CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)) {
+ spin_unlock(&tcon->ses->server->srv_lock);
+ rc = -EACCES;
+ goto out;
+ }
+ spin_unlock(&tcon->ses->server->srv_lock);
+ } else
+#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
+ tcon->unix_ext = 0; /* server does not support them */
+
+ /* do not care if a following call succeed - informational */
+ if (!tcon->pipe && server->ops->qfs_tcon) {
+ server->ops->qfs_tcon(xid, tcon, cifs_sb);
+ if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RO_CACHE) {
+ if (tcon->fsDevInfo.DeviceCharacteristics &
+ cpu_to_le32(FILE_READ_ONLY_DEVICE))
+ cifs_dbg(VFS, "mounted to read only share\n");
+ else if ((cifs_sb->mnt_cifs_flags &
+ CIFS_MOUNT_RW_CACHE) == 0)
+ cifs_dbg(VFS, "read only mount of RW share\n");
+ /* no need to log a RW mount of a typical RW share */
+ }
+ }
+
+ /*
+ * Clamp the rsize/wsize mount arguments if they are too big for the server
+ * and set the rsize/wsize to the negotiated values if not passed in by
+ * the user on mount
+ */
+ if ((cifs_sb->ctx->wsize == 0) ||
+ (cifs_sb->ctx->wsize > server->ops->negotiate_wsize(tcon, ctx)))
+ cifs_sb->ctx->wsize = server->ops->negotiate_wsize(tcon, ctx);
+ if ((cifs_sb->ctx->rsize == 0) ||
+ (cifs_sb->ctx->rsize > server->ops->negotiate_rsize(tcon, ctx)))
+ cifs_sb->ctx->rsize = server->ops->negotiate_rsize(tcon, ctx);
+
+ /*
+ * The cookie is initialized from volume info returned above.
+ * Inside cifs_fscache_get_super_cookie it checks
+ * that we do not get super cookie twice.
+ */
+ if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_FSCACHE)
+ cifs_fscache_get_super_cookie(tcon);
+
+out:
+ mnt_ctx->server = server;
+ mnt_ctx->ses = ses;
+ mnt_ctx->tcon = tcon;
+ mnt_ctx->xid = xid;
+
+ return rc;
+}
+
+static int mount_setup_tlink(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
+ struct cifs_tcon *tcon)
+{
+ struct tcon_link *tlink;
+
+ /* hang the tcon off of the superblock */
+ tlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
+ if (tlink == NULL)
+ return -ENOMEM;
+
+ tlink->tl_uid = ses->linux_uid;
+ tlink->tl_tcon = tcon;
+ tlink->tl_time = jiffies;
+ set_bit(TCON_LINK_MASTER, &tlink->tl_flags);
+ set_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
+
+ cifs_sb->master_tlink = tlink;
+ spin_lock(&cifs_sb->tlink_tree_lock);
+ tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
+ spin_unlock(&cifs_sb->tlink_tree_lock);
+
+ queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
+ TLINK_IDLE_EXPIRE);
+ return 0;
+}
+
+#ifdef CONFIG_CIFS_DFS_UPCALL
+/* Get unique dfs connections */
+static int mount_get_dfs_conns(struct mount_ctx *mnt_ctx)
+{
+ int rc;
+
+ mnt_ctx->fs_ctx->nosharesock = true;
+ rc = mount_get_conns(mnt_ctx);
+ if (mnt_ctx->server) {
+ cifs_dbg(FYI, "%s: marking tcp session as a dfs connection\n", __func__);
+ spin_lock(&mnt_ctx->server->srv_lock);
+ mnt_ctx->server->is_dfs_conn = true;
+ spin_unlock(&mnt_ctx->server->srv_lock);
+ }
+ return rc;
+}
+
+/*
+ * cifs_build_path_to_root returns full path to root when we do not have an
+ * existing connection (tcon)
+ */
+static char *
+build_unc_path_to_root(const struct smb3_fs_context *ctx,
+ const struct cifs_sb_info *cifs_sb, bool useppath)
+{
+ char *full_path, *pos;
+ unsigned int pplen = useppath && ctx->prepath ?
+ strlen(ctx->prepath) + 1 : 0;
+ unsigned int unc_len = strnlen(ctx->UNC, MAX_TREE_SIZE + 1);
+
+ if (unc_len > MAX_TREE_SIZE)
+ return ERR_PTR(-EINVAL);
+
+ full_path = kmalloc(unc_len + pplen + 1, GFP_KERNEL);
+ if (full_path == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ memcpy(full_path, ctx->UNC, unc_len);
+ pos = full_path + unc_len;
+
+ if (pplen) {
+ *pos = CIFS_DIR_SEP(cifs_sb);
+ memcpy(pos + 1, ctx->prepath, pplen);
+ pos += pplen;
+ }
+
+ *pos = '\0'; /* add trailing null */
+ convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
+ cifs_dbg(FYI, "%s: full_path=%s\n", __func__, full_path);
+ return full_path;
+}
+
+/*
+ * expand_dfs_referral - Update cifs_sb from dfs referral path
+ *
+ * cifs_sb->ctx->mount_options will be (re-)allocated to a string containing updated options for the
+ * submount. Otherwise it will be left untouched.
+ */
+static int expand_dfs_referral(struct mount_ctx *mnt_ctx, const char *full_path,
+ struct dfs_info3_param *referral)
+{
+ int rc;
+ struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
+ struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
+ char *fake_devname = NULL, *mdata = NULL;
+
+ mdata = cifs_compose_mount_options(cifs_sb->ctx->mount_options, full_path + 1, referral,
+ &fake_devname);
+ if (IS_ERR(mdata)) {
+ rc = PTR_ERR(mdata);
+ mdata = NULL;
+ } else {
+ /*
+ * We can not clear out the whole structure since we no longer have an explicit
+ * function to parse a mount-string. Instead we need to clear out the individual
+ * fields that are no longer valid.
+ */
+ kfree(ctx->prepath);
+ ctx->prepath = NULL;
+ rc = cifs_setup_volume_info(ctx, mdata, fake_devname);
+ }
+ kfree(fake_devname);
+ kfree(cifs_sb->ctx->mount_options);
+ cifs_sb->ctx->mount_options = mdata;
+
+ return rc;
+}
+#endif
+
+/* TODO: all callers to this are broken. We are not parsing mount_options here
+ * we should pass a clone of the original context?
+ */
+int
+cifs_setup_volume_info(struct smb3_fs_context *ctx, const char *mntopts, const char *devname)
+{
+ int rc;
+
+ if (devname) {
+ cifs_dbg(FYI, "%s: devname=%s\n", __func__, devname);
+ rc = smb3_parse_devname(devname, ctx);
+ if (rc) {
+ cifs_dbg(VFS, "%s: failed to parse %s: %d\n", __func__, devname, rc);
+ return rc;
+ }
+ }
+
+ if (mntopts) {
+ char *ip;
+
+ rc = smb3_parse_opt(mntopts, "ip", &ip);
+ if (rc) {
+ cifs_dbg(VFS, "%s: failed to parse ip options: %d\n", __func__, rc);
+ return rc;
+ }
+
+ rc = cifs_convert_address((struct sockaddr *)&ctx->dstaddr, ip, strlen(ip));
+ kfree(ip);
+ if (!rc) {
+ cifs_dbg(VFS, "%s: failed to convert ip address\n", __func__);
+ return -EINVAL;
+ }
+ }
+
+ if (ctx->nullauth) {
+ cifs_dbg(FYI, "Anonymous login\n");
+ kfree(ctx->username);
+ ctx->username = NULL;
+ } else if (ctx->username) {
+ /* BB fixme parse for domain name here */
+ cifs_dbg(FYI, "Username: %s\n", ctx->username);
+ } else {
+ cifs_dbg(VFS, "No username specified\n");
+ /* In userspace mount helper we can get user name from alternate
+ locations such as env variables and files on disk */
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int
+cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
+ unsigned int xid,
+ struct cifs_tcon *tcon,
+ struct cifs_sb_info *cifs_sb,
+ char *full_path,
+ int added_treename)
+{
+ int rc;
+ char *s;
+ char sep, tmp;
+ int skip = added_treename ? 1 : 0;
+
+ sep = CIFS_DIR_SEP(cifs_sb);
+ s = full_path;
+
+ rc = server->ops->is_path_accessible(xid, tcon, cifs_sb, "");
+ while (rc == 0) {
+ /* skip separators */
+ while (*s == sep)
+ s++;
+ if (!*s)
+ break;
+ /* next separator */
+ while (*s && *s != sep)
+ s++;
+ /*
+ * if the treename is added, we then have to skip the first
+ * part within the separators
+ */
+ if (skip) {
+ skip = 0;
+ continue;
+ }
+ /*
+ * temporarily null-terminate the path at the end of
+ * the current component
+ */
+ tmp = *s;
+ *s = 0;
+ rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
+ full_path);
+ *s = tmp;
+ }
+ return rc;
+}
+
+/*
+ * Check if path is remote (i.e. a DFS share).
+ *
+ * Return -EREMOTE if it is, otherwise 0 or -errno.
+ */
+static int is_path_remote(struct mount_ctx *mnt_ctx)
+{
+ int rc;
+ struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
+ struct TCP_Server_Info *server = mnt_ctx->server;
+ unsigned int xid = mnt_ctx->xid;
+ struct cifs_tcon *tcon = mnt_ctx->tcon;
+ struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
+ char *full_path;
+
+ if (!server->ops->is_path_accessible)
+ return -EOPNOTSUPP;
+
+ /*
+ * cifs_build_path_to_root works only when we have a valid tcon
+ */
+ full_path = cifs_build_path_to_root(ctx, cifs_sb, tcon,
+ tcon->Flags & SMB_SHARE_IS_IN_DFS);
+ if (full_path == NULL)
+ return -ENOMEM;
+
+ cifs_dbg(FYI, "%s: full_path: %s\n", __func__, full_path);
+
+ rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
+ full_path);
+ if (rc != 0 && rc != -EREMOTE)
+ goto out;
+
+ if (rc != -EREMOTE) {
+ rc = cifs_are_all_path_components_accessible(server, xid, tcon,
+ cifs_sb, full_path, tcon->Flags & SMB_SHARE_IS_IN_DFS);
+ if (rc != 0) {
+ cifs_server_dbg(VFS, "cannot query dirs between root and final path, enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
+ cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
+ rc = 0;
+ }
+ }
+
+out:
+ kfree(full_path);
+ return rc;
+}
+
+#ifdef CONFIG_CIFS_DFS_UPCALL
+static void set_root_ses(struct mount_ctx *mnt_ctx)
+{
+ if (mnt_ctx->ses) {
+ spin_lock(&cifs_tcp_ses_lock);
+ mnt_ctx->ses->ses_count++;
+ spin_unlock(&cifs_tcp_ses_lock);
+ dfs_cache_add_refsrv_session(&mnt_ctx->mount_id, mnt_ctx->ses);
+ }
+ mnt_ctx->root_ses = mnt_ctx->ses;
+}
+
+static int is_dfs_mount(struct mount_ctx *mnt_ctx, bool *isdfs, struct dfs_cache_tgt_list *root_tl)
+{
+ int rc;
+ struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
+ struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
+
+ *isdfs = true;
+
+ rc = mount_get_conns(mnt_ctx);
+ /*
+ * If called with 'nodfs' mount option, then skip DFS resolving. Otherwise unconditionally
+ * try to get an DFS referral (even cached) to determine whether it is an DFS mount.
+ *
+ * Skip prefix path to provide support for DFS referrals from w2k8 servers which don't seem
+ * to respond with PATH_NOT_COVERED to requests that include the prefix.
+ */
+ if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS) ||
+ dfs_cache_find(mnt_ctx->xid, mnt_ctx->ses, cifs_sb->local_nls, cifs_remap(cifs_sb),
+ ctx->UNC + 1, NULL, root_tl)) {
+ if (rc)
+ return rc;
+ /* Check if it is fully accessible and then mount it */
+ rc = is_path_remote(mnt_ctx);
+ if (!rc)
+ *isdfs = false;
+ else if (rc != -EREMOTE)
+ return rc;
+ }
+ return 0;
+}
+
+static int connect_dfs_target(struct mount_ctx *mnt_ctx, const char *full_path,
+ const char *ref_path, struct dfs_cache_tgt_iterator *tit)
+{
+ int rc;
+ struct dfs_info3_param ref = {};
+ struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
+ char *oldmnt = cifs_sb->ctx->mount_options;
+
+ cifs_dbg(FYI, "%s: full_path=%s ref_path=%s target=%s\n", __func__, full_path, ref_path,
+ dfs_cache_get_tgt_name(tit));
+
+ rc = dfs_cache_get_tgt_referral(ref_path, tit, &ref);
+ if (rc)
+ goto out;
+
+ rc = expand_dfs_referral(mnt_ctx, full_path, &ref);
+ if (rc)
+ goto out;
+
+ /* Connect to new target only if we were redirected (e.g. mount options changed) */
+ if (oldmnt != cifs_sb->ctx->mount_options) {
+ mount_put_conns(mnt_ctx);
+ rc = mount_get_dfs_conns(mnt_ctx);
+ }
+ if (!rc) {
+ if (cifs_is_referral_server(mnt_ctx->tcon, &ref))
+ set_root_ses(mnt_ctx);
+ rc = dfs_cache_update_tgthint(mnt_ctx->xid, mnt_ctx->root_ses, cifs_sb->local_nls,
+ cifs_remap(cifs_sb), ref_path, tit);
+ }
+
+out:
+ free_dfs_info_param(&ref);
+ return rc;
+}
+
+static int connect_dfs_root(struct mount_ctx *mnt_ctx, struct dfs_cache_tgt_list *root_tl)
+{
+ int rc;
+ char *full_path;
+ struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
+ struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
+ struct dfs_cache_tgt_iterator *tit;
+
+ /* Put initial connections as they might be shared with other mounts. We need unique dfs
+ * connections per mount to properly failover, so mount_get_dfs_conns() must be used from
+ * now on.
+ */
+ mount_put_conns(mnt_ctx);
+ mount_get_dfs_conns(mnt_ctx);
+ set_root_ses(mnt_ctx);
+
+ full_path = build_unc_path_to_root(ctx, cifs_sb, true);
+ if (IS_ERR(full_path))
+ return PTR_ERR(full_path);
+
+ mnt_ctx->origin_fullpath = dfs_cache_canonical_path(ctx->UNC, cifs_sb->local_nls,
+ cifs_remap(cifs_sb));
+ if (IS_ERR(mnt_ctx->origin_fullpath)) {
+ rc = PTR_ERR(mnt_ctx->origin_fullpath);
+ mnt_ctx->origin_fullpath = NULL;
+ goto out;
+ }
+
+ /* Try all dfs root targets */
+ for (rc = -ENOENT, tit = dfs_cache_get_tgt_iterator(root_tl);
+ tit; tit = dfs_cache_get_next_tgt(root_tl, tit)) {
+ rc = connect_dfs_target(mnt_ctx, full_path, mnt_ctx->origin_fullpath + 1, tit);
+ if (!rc) {
+ mnt_ctx->leaf_fullpath = kstrdup(mnt_ctx->origin_fullpath, GFP_KERNEL);
+ if (!mnt_ctx->leaf_fullpath)
+ rc = -ENOMEM;
+ break;
+ }
+ }
+
+out:
+ kfree(full_path);
+ return rc;
+}
+
+static int __follow_dfs_link(struct mount_ctx *mnt_ctx)
+{
+ int rc;
+ struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
+ struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
+ char *full_path;
+ struct dfs_cache_tgt_list tl = DFS_CACHE_TGT_LIST_INIT(tl);
+ struct dfs_cache_tgt_iterator *tit;
+
+ full_path = build_unc_path_to_root(ctx, cifs_sb, true);
+ if (IS_ERR(full_path))
+ return PTR_ERR(full_path);
+
+ kfree(mnt_ctx->leaf_fullpath);
+ mnt_ctx->leaf_fullpath = dfs_cache_canonical_path(full_path, cifs_sb->local_nls,
+ cifs_remap(cifs_sb));
+ if (IS_ERR(mnt_ctx->leaf_fullpath)) {
+ rc = PTR_ERR(mnt_ctx->leaf_fullpath);
+ mnt_ctx->leaf_fullpath = NULL;
+ goto out;
+ }
+
+ /* Get referral from dfs link */
+ rc = dfs_cache_find(mnt_ctx->xid, mnt_ctx->root_ses, cifs_sb->local_nls,
+ cifs_remap(cifs_sb), mnt_ctx->leaf_fullpath + 1, NULL, &tl);
+ if (rc)
+ goto out;
+
+ /* Try all dfs link targets. If an I/O fails from currently connected DFS target with an
+ * error other than STATUS_PATH_NOT_COVERED (-EREMOTE), then retry it from other targets as
+ * specified in MS-DFSC "3.1.5.2 I/O Operation to Target Fails with an Error Other Than
+ * STATUS_PATH_NOT_COVERED."
+ */
+ for (rc = -ENOENT, tit = dfs_cache_get_tgt_iterator(&tl);
+ tit; tit = dfs_cache_get_next_tgt(&tl, tit)) {
+ rc = connect_dfs_target(mnt_ctx, full_path, mnt_ctx->leaf_fullpath + 1, tit);
+ if (!rc) {
+ rc = is_path_remote(mnt_ctx);
+ if (!rc || rc == -EREMOTE)
+ break;
+ }
+ }
+
+out:
+ kfree(full_path);
+ dfs_cache_free_tgts(&tl);
+ return rc;
+}
+
+static int follow_dfs_link(struct mount_ctx *mnt_ctx)
+{
+ int rc;
+ struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
+ struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
+ char *full_path;
+ int num_links = 0;
+
+ full_path = build_unc_path_to_root(ctx, cifs_sb, true);
+ if (IS_ERR(full_path))
+ return PTR_ERR(full_path);
+
+ kfree(mnt_ctx->origin_fullpath);
+ mnt_ctx->origin_fullpath = dfs_cache_canonical_path(full_path, cifs_sb->local_nls,
+ cifs_remap(cifs_sb));
+ kfree(full_path);
+
+ if (IS_ERR(mnt_ctx->origin_fullpath)) {
+ rc = PTR_ERR(mnt_ctx->origin_fullpath);
+ mnt_ctx->origin_fullpath = NULL;
+ return rc;
+ }
+
+ do {
+ rc = __follow_dfs_link(mnt_ctx);
+ if (!rc || rc != -EREMOTE)
+ break;
+ } while (rc = -ELOOP, ++num_links < MAX_NESTED_LINKS);
+
+ return rc;
+}
+
+/* Set up DFS referral paths for failover */
+static void setup_server_referral_paths(struct mount_ctx *mnt_ctx)
+{
+ struct TCP_Server_Info *server = mnt_ctx->server;
+
+ mutex_lock(&server->refpath_lock);
+ server->origin_fullpath = mnt_ctx->origin_fullpath;
+ server->leaf_fullpath = mnt_ctx->leaf_fullpath;
+ server->current_fullpath = mnt_ctx->leaf_fullpath;
+ mutex_unlock(&server->refpath_lock);
+ mnt_ctx->origin_fullpath = mnt_ctx->leaf_fullpath = NULL;
+}
+
+int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
+{
+ int rc;
+ struct mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
+ struct dfs_cache_tgt_list tl = DFS_CACHE_TGT_LIST_INIT(tl);
+ bool isdfs;
+
+ rc = is_dfs_mount(&mnt_ctx, &isdfs, &tl);
+ if (rc)
+ goto error;
+ if (!isdfs)
+ goto out;
+
+ /* proceed as DFS mount */
+ uuid_gen(&mnt_ctx.mount_id);
+ rc = connect_dfs_root(&mnt_ctx, &tl);
+ dfs_cache_free_tgts(&tl);
+
+ if (rc)
+ goto error;
+
+ rc = is_path_remote(&mnt_ctx);
+ if (rc)
+ rc = follow_dfs_link(&mnt_ctx);
+ if (rc)
+ goto error;
+
+ setup_server_referral_paths(&mnt_ctx);
+ /*
+ * After reconnecting to a different server, unique ids won't match anymore, so we disable
+ * serverino. This prevents dentry revalidation to think the dentry are stale (ESTALE).
+ */
+ cifs_autodisable_serverino(cifs_sb);
+ /*
+ * Force the use of prefix path to support failover on DFS paths that resolve to targets
+ * that have different prefix paths.
+ */
+ cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
+ kfree(cifs_sb->prepath);
+ cifs_sb->prepath = ctx->prepath;
+ ctx->prepath = NULL;
+ uuid_copy(&cifs_sb->dfs_mount_id, &mnt_ctx.mount_id);
+
+out:
+ cifs_try_adding_channels(cifs_sb, mnt_ctx.ses);
+ rc = mount_setup_tlink(cifs_sb, mnt_ctx.ses, mnt_ctx.tcon);
+ if (rc)
+ goto error;
+
+ free_xid(mnt_ctx.xid);
+ return rc;
+
+error:
+ dfs_cache_put_refsrv_sessions(&mnt_ctx.mount_id);
+ kfree(mnt_ctx.origin_fullpath);
+ kfree(mnt_ctx.leaf_fullpath);
+ mount_put_conns(&mnt_ctx);
+ return rc;
+}
+#else
+int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
+{
+ int rc = 0;
+ struct mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
+
+ rc = mount_get_conns(&mnt_ctx);
+ if (rc)
+ goto error;
+
+ if (mnt_ctx.tcon) {
+ rc = is_path_remote(&mnt_ctx);
+ if (rc == -EREMOTE)
+ rc = -EOPNOTSUPP;
+ if (rc)
+ goto error;
+ }
+
+ rc = mount_setup_tlink(cifs_sb, mnt_ctx.ses, mnt_ctx.tcon);
+ if (rc)
+ goto error;
+
+ free_xid(mnt_ctx.xid);
+ return rc;
+
+error:
+ mount_put_conns(&mnt_ctx);
+ return rc;
+}
+#endif
+
+/*
+ * Issue a TREE_CONNECT request.
+ */
+int
+CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
+ const char *tree, struct cifs_tcon *tcon,
+ const struct nls_table *nls_codepage)
+{
+ struct smb_hdr *smb_buffer;
+ struct smb_hdr *smb_buffer_response;
+ TCONX_REQ *pSMB;
+ TCONX_RSP *pSMBr;
+ unsigned char *bcc_ptr;
+ int rc = 0;
+ int length;
+ __u16 bytes_left, count;
+
+ if (ses == NULL)
+ return -EIO;
+
+ smb_buffer = cifs_buf_get();
+ if (smb_buffer == NULL)
+ return -ENOMEM;
+
+ smb_buffer_response = smb_buffer;
+
+ header_assemble(smb_buffer, SMB_COM_TREE_CONNECT_ANDX,
+ NULL /*no tid */ , 4 /*wct */ );
+
+ smb_buffer->Mid = get_next_mid(ses->server);
+ smb_buffer->Uid = ses->Suid;
+ pSMB = (TCONX_REQ *) smb_buffer;
+ pSMBr = (TCONX_RSP *) smb_buffer_response;
+
+ pSMB->AndXCommand = 0xFF;
+ pSMB->Flags = cpu_to_le16(TCON_EXTENDED_SECINFO);
+ bcc_ptr = &pSMB->Password[0];
+
+ pSMB->PasswordLength = cpu_to_le16(1); /* minimum */
+ *bcc_ptr = 0; /* password is null byte */
+ bcc_ptr++; /* skip password */
+ /* already aligned so no need to do it below */
+
+ if (ses->server->sign)
+ smb_buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
+
+ if (ses->capabilities & CAP_STATUS32) {
+ smb_buffer->Flags2 |= SMBFLG2_ERR_STATUS;
+ }
+ if (ses->capabilities & CAP_DFS) {
+ smb_buffer->Flags2 |= SMBFLG2_DFS;
+ }
+ if (ses->capabilities & CAP_UNICODE) {
+ smb_buffer->Flags2 |= SMBFLG2_UNICODE;
+ length =
+ cifs_strtoUTF16((__le16 *) bcc_ptr, tree,
+ 6 /* max utf8 char length in bytes */ *
+ (/* server len*/ + 256 /* share len */), nls_codepage);
+ bcc_ptr += 2 * length; /* convert num 16 bit words to bytes */
+ bcc_ptr += 2; /* skip trailing null */
+ } else { /* ASCII */
+ strcpy(bcc_ptr, tree);
+ bcc_ptr += strlen(tree) + 1;
+ }
+ strcpy(bcc_ptr, "?????");
+ bcc_ptr += strlen("?????");
+ bcc_ptr += 1;
+ count = bcc_ptr - &pSMB->Password[0];
+ be32_add_cpu(&pSMB->hdr.smb_buf_length, count);
+ pSMB->ByteCount = cpu_to_le16(count);
+
+ rc = SendReceive(xid, ses, smb_buffer, smb_buffer_response, &length,
+ 0);
+
+ /* above now done in SendReceive */
+ if (rc == 0) {
+ bool is_unicode;
+
+ tcon->tid = smb_buffer_response->Tid;
+ bcc_ptr = pByteArea(smb_buffer_response);
+ bytes_left = get_bcc(smb_buffer_response);
+ length = strnlen(bcc_ptr, bytes_left - 2);
+ if (smb_buffer->Flags2 & SMBFLG2_UNICODE)
+ is_unicode = true;
+ else
+ is_unicode = false;
+
+
+ /* skip service field (NB: this field is always ASCII) */
+ if (length == 3) {
+ if ((bcc_ptr[0] == 'I') && (bcc_ptr[1] == 'P') &&
+ (bcc_ptr[2] == 'C')) {
+ cifs_dbg(FYI, "IPC connection\n");
+ tcon->ipc = true;
+ tcon->pipe = true;
+ }
+ } else if (length == 2) {
+ if ((bcc_ptr[0] == 'A') && (bcc_ptr[1] == ':')) {
+ /* the most common case */
+ cifs_dbg(FYI, "disk share connection\n");
+ }
+ }
+ bcc_ptr += length + 1;
+ bytes_left -= (length + 1);
+ strscpy(tcon->tree_name, tree, sizeof(tcon->tree_name));
+
+ /* mostly informational -- no need to fail on error here */
+ kfree(tcon->nativeFileSystem);
+ tcon->nativeFileSystem = cifs_strndup_from_utf16(bcc_ptr,
+ bytes_left, is_unicode,
+ nls_codepage);
+
+ cifs_dbg(FYI, "nativeFileSystem=%s\n", tcon->nativeFileSystem);
+
+ if ((smb_buffer_response->WordCount == 3) ||
+ (smb_buffer_response->WordCount == 7))
+ /* field is in same location */
+ tcon->Flags = le16_to_cpu(pSMBr->OptionalSupport);
+ else
+ tcon->Flags = 0;
+ cifs_dbg(FYI, "Tcon flags: 0x%x\n", tcon->Flags);
+ }
+
+ cifs_buf_release(smb_buffer);
+ return rc;
+}
+
+static void delayed_free(struct rcu_head *p)
+{
+ struct cifs_sb_info *cifs_sb = container_of(p, struct cifs_sb_info, rcu);
+
+ unload_nls(cifs_sb->local_nls);
+ smb3_cleanup_fs_context(cifs_sb->ctx);
+ kfree(cifs_sb);
+}
+
+void
+cifs_umount(struct cifs_sb_info *cifs_sb)
+{
+ struct rb_root *root = &cifs_sb->tlink_tree;
+ struct rb_node *node;
+ struct tcon_link *tlink;
+
+ cancel_delayed_work_sync(&cifs_sb->prune_tlinks);
+
+ spin_lock(&cifs_sb->tlink_tree_lock);
+ while ((node = rb_first(root))) {
+ tlink = rb_entry(node, struct tcon_link, tl_rbnode);
+ cifs_get_tlink(tlink);
+ clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
+ rb_erase(node, root);
+
+ spin_unlock(&cifs_sb->tlink_tree_lock);
+ cifs_put_tlink(tlink);
+ spin_lock(&cifs_sb->tlink_tree_lock);
+ }
+ spin_unlock(&cifs_sb->tlink_tree_lock);
+
+ kfree(cifs_sb->prepath);
+#ifdef CONFIG_CIFS_DFS_UPCALL
+ dfs_cache_put_refsrv_sessions(&cifs_sb->dfs_mount_id);
+#endif
+ call_rcu(&cifs_sb->rcu, delayed_free);
+}
+
+int
+cifs_negotiate_protocol(const unsigned int xid, struct cifs_ses *ses,
+ struct TCP_Server_Info *server)
+{
+ int rc = 0;
+
+ if (!server->ops->need_neg || !server->ops->negotiate)
+ return -ENOSYS;
+
+ /* only send once per connect */
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus != CifsGood &&
+ server->tcpStatus != CifsNew &&
+ server->tcpStatus != CifsNeedNegotiate) {
+ spin_unlock(&server->srv_lock);
+ return -EHOSTDOWN;
+ }
+
+ if (!server->ops->need_neg(server) &&
+ server->tcpStatus == CifsGood) {
+ spin_unlock(&server->srv_lock);
+ return 0;
+ }
+
+ server->tcpStatus = CifsInNegotiate;
+ spin_unlock(&server->srv_lock);
+
+ rc = server->ops->negotiate(xid, ses, server);
+ if (rc == 0) {
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus == CifsInNegotiate)
+ server->tcpStatus = CifsGood;
+ else
+ rc = -EHOSTDOWN;
+ spin_unlock(&server->srv_lock);
+ } else {
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus == CifsInNegotiate)
+ server->tcpStatus = CifsNeedNegotiate;
+ spin_unlock(&server->srv_lock);
+ }
+
+ return rc;
+}
+
+int
+cifs_setup_session(const unsigned int xid, struct cifs_ses *ses,
+ struct TCP_Server_Info *server,
+ struct nls_table *nls_info)
+{
+ int rc = -ENOSYS;
+ struct TCP_Server_Info *pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
+ struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&pserver->dstaddr;
+ struct sockaddr_in *addr = (struct sockaddr_in *)&pserver->dstaddr;
+ bool is_binding = false;
+
+ spin_lock(&ses->ses_lock);
+ cifs_dbg(FYI, "%s: channel connect bitmap: 0x%lx\n",
+ __func__, ses->chans_need_reconnect);
+
+ if (ses->ses_status != SES_GOOD &&
+ ses->ses_status != SES_NEW &&
+ ses->ses_status != SES_NEED_RECON) {
+ spin_unlock(&ses->ses_lock);
+ return -EHOSTDOWN;
+ }
+
+ /* only send once per connect */
+ spin_lock(&ses->chan_lock);
+ if (CIFS_ALL_CHANS_GOOD(ses)) {
+ if (ses->ses_status == SES_NEED_RECON)
+ ses->ses_status = SES_GOOD;
+ spin_unlock(&ses->chan_lock);
+ spin_unlock(&ses->ses_lock);
+ return 0;
+ }
+
+ cifs_chan_set_in_reconnect(ses, server);
+ is_binding = !CIFS_ALL_CHANS_NEED_RECONNECT(ses);
+ spin_unlock(&ses->chan_lock);
+
+ if (!is_binding) {
+ ses->ses_status = SES_IN_SETUP;
+
+ /* force iface_list refresh */
+ ses->iface_last_update = 0;
+ }
+ spin_unlock(&ses->ses_lock);
+
+ /* update ses ip_addr only for primary chan */
+ if (server == pserver) {
+ if (server->dstaddr.ss_family == AF_INET6)
+ scnprintf(ses->ip_addr, sizeof(ses->ip_addr), "%pI6", &addr6->sin6_addr);
+ else
+ scnprintf(ses->ip_addr, sizeof(ses->ip_addr), "%pI4", &addr->sin_addr);
+ }
+
+ if (!is_binding) {
+ ses->capabilities = server->capabilities;
+ if (!linuxExtEnabled)
+ ses->capabilities &= (~server->vals->cap_unix);
+
+ if (ses->auth_key.response) {
+ cifs_dbg(FYI, "Free previous auth_key.response = %p\n",
+ ses->auth_key.response);
+ kfree_sensitive(ses->auth_key.response);
+ ses->auth_key.response = NULL;
+ ses->auth_key.len = 0;
+ }
+ }
+
+ cifs_dbg(FYI, "Security Mode: 0x%x Capabilities: 0x%x TimeAdjust: %d\n",
+ server->sec_mode, server->capabilities, server->timeAdj);
+
+ if (server->ops->sess_setup)
+ rc = server->ops->sess_setup(xid, ses, server, nls_info);
+
+ if (rc) {
+ cifs_server_dbg(VFS, "Send error in SessSetup = %d\n", rc);
+ spin_lock(&ses->ses_lock);
+ if (ses->ses_status == SES_IN_SETUP)
+ ses->ses_status = SES_NEED_RECON;
+ spin_lock(&ses->chan_lock);
+ cifs_chan_clear_in_reconnect(ses, server);
+ spin_unlock(&ses->chan_lock);
+ spin_unlock(&ses->ses_lock);
+ } else {
+ spin_lock(&ses->ses_lock);
+ if (ses->ses_status == SES_IN_SETUP)
+ ses->ses_status = SES_GOOD;
+ spin_lock(&ses->chan_lock);
+ cifs_chan_clear_in_reconnect(ses, server);
+ cifs_chan_clear_need_reconnect(ses, server);
+ spin_unlock(&ses->chan_lock);
+ spin_unlock(&ses->ses_lock);
+ }
+
+ return rc;
+}
+
+static int
+cifs_set_vol_auth(struct smb3_fs_context *ctx, struct cifs_ses *ses)
+{
+ ctx->sectype = ses->sectype;
+
+ /* krb5 is special, since we don't need username or pw */
+ if (ctx->sectype == Kerberos)
+ return 0;
+
+ return cifs_set_cifscreds(ctx, ses);
+}
+
+static struct cifs_tcon *
+cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
+{
+ int rc;
+ struct cifs_tcon *master_tcon = cifs_sb_master_tcon(cifs_sb);
+ struct cifs_ses *ses;
+ struct cifs_tcon *tcon = NULL;
+ struct smb3_fs_context *ctx;
+
+ ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+ if (ctx == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ ctx->local_nls = cifs_sb->local_nls;
+ ctx->linux_uid = fsuid;
+ ctx->cred_uid = fsuid;
+ ctx->UNC = master_tcon->tree_name;
+ ctx->retry = master_tcon->retry;
+ ctx->nocase = master_tcon->nocase;
+ ctx->nohandlecache = master_tcon->nohandlecache;
+ ctx->local_lease = master_tcon->local_lease;
+ ctx->no_lease = master_tcon->no_lease;
+ ctx->resilient = master_tcon->use_resilient;
+ ctx->persistent = master_tcon->use_persistent;
+ ctx->handle_timeout = master_tcon->handle_timeout;
+ ctx->no_linux_ext = !master_tcon->unix_ext;
+ ctx->linux_ext = master_tcon->posix_extensions;
+ ctx->sectype = master_tcon->ses->sectype;
+ ctx->sign = master_tcon->ses->sign;
+ ctx->seal = master_tcon->seal;
+ ctx->witness = master_tcon->use_witness;
+
+ rc = cifs_set_vol_auth(ctx, master_tcon->ses);
+ if (rc) {
+ tcon = ERR_PTR(rc);
+ goto out;
+ }
+
+ /* get a reference for the same TCP session */
+ spin_lock(&cifs_tcp_ses_lock);
+ ++master_tcon->ses->server->srv_count;
+ spin_unlock(&cifs_tcp_ses_lock);
+
+ ses = cifs_get_smb_ses(master_tcon->ses->server, ctx);
+ if (IS_ERR(ses)) {
+ tcon = (struct cifs_tcon *)ses;
+ cifs_put_tcp_session(master_tcon->ses->server, 0);
+ goto out;
+ }
+
+ tcon = cifs_get_tcon(ses, ctx);
+ if (IS_ERR(tcon)) {
+ cifs_put_smb_ses(ses);
+ goto out;
+ }
+
+#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
+ if (cap_unix(ses))
+ reset_cifs_unix_caps(0, tcon, NULL, ctx);
+#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
+
+out:
+ kfree(ctx->username);
+ kfree_sensitive(ctx->password);
+ kfree(ctx);
+
+ return tcon;
+}
+
+struct cifs_tcon *
+cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb)
+{
+ return tlink_tcon(cifs_sb_master_tlink(cifs_sb));
+}
+
+/* find and return a tlink with given uid */
+static struct tcon_link *
+tlink_rb_search(struct rb_root *root, kuid_t uid)
+{
+ struct rb_node *node = root->rb_node;
+ struct tcon_link *tlink;
+
+ while (node) {
+ tlink = rb_entry(node, struct tcon_link, tl_rbnode);
+
+ if (uid_gt(tlink->tl_uid, uid))
+ node = node->rb_left;
+ else if (uid_lt(tlink->tl_uid, uid))
+ node = node->rb_right;
+ else
+ return tlink;
+ }
+ return NULL;
+}
+
+/* insert a tcon_link into the tree */
+static void
+tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink)
+{
+ struct rb_node **new = &(root->rb_node), *parent = NULL;
+ struct tcon_link *tlink;
+
+ while (*new) {
+ tlink = rb_entry(*new, struct tcon_link, tl_rbnode);
+ parent = *new;
+
+ if (uid_gt(tlink->tl_uid, new_tlink->tl_uid))
+ new = &((*new)->rb_left);
+ else
+ new = &((*new)->rb_right);
+ }
+
+ rb_link_node(&new_tlink->tl_rbnode, parent, new);
+ rb_insert_color(&new_tlink->tl_rbnode, root);
+}
+
+/*
+ * Find or construct an appropriate tcon given a cifs_sb and the fsuid of the
+ * current task.
+ *
+ * If the superblock doesn't refer to a multiuser mount, then just return
+ * the master tcon for the mount.
+ *
+ * First, search the rbtree for an existing tcon for this fsuid. If one
+ * exists, then check to see if it's pending construction. If it is then wait
+ * for construction to complete. Once it's no longer pending, check to see if
+ * it failed and either return an error or retry construction, depending on
+ * the timeout.
+ *
+ * If one doesn't exist then insert a new tcon_link struct into the tree and
+ * try to construct a new one.
+ */
+struct tcon_link *
+cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
+{
+ int ret;
+ kuid_t fsuid = current_fsuid();
+ struct tcon_link *tlink, *newtlink;
+
+ if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
+ return cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
+
+ spin_lock(&cifs_sb->tlink_tree_lock);
+ tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
+ if (tlink)
+ cifs_get_tlink(tlink);
+ spin_unlock(&cifs_sb->tlink_tree_lock);
+
+ if (tlink == NULL) {
+ newtlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
+ if (newtlink == NULL)
+ return ERR_PTR(-ENOMEM);
+ newtlink->tl_uid = fsuid;
+ newtlink->tl_tcon = ERR_PTR(-EACCES);
+ set_bit(TCON_LINK_PENDING, &newtlink->tl_flags);
+ set_bit(TCON_LINK_IN_TREE, &newtlink->tl_flags);
+ cifs_get_tlink(newtlink);
+
+ spin_lock(&cifs_sb->tlink_tree_lock);
+ /* was one inserted after previous search? */
+ tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
+ if (tlink) {
+ cifs_get_tlink(tlink);
+ spin_unlock(&cifs_sb->tlink_tree_lock);
+ kfree(newtlink);
+ goto wait_for_construction;
+ }
+ tlink = newtlink;
+ tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
+ spin_unlock(&cifs_sb->tlink_tree_lock);
+ } else {
+wait_for_construction:
+ ret = wait_on_bit(&tlink->tl_flags, TCON_LINK_PENDING,
+ TASK_INTERRUPTIBLE);
+ if (ret) {
+ cifs_put_tlink(tlink);
+ return ERR_PTR(-ERESTARTSYS);
+ }
+
+ /* if it's good, return it */
+ if (!IS_ERR(tlink->tl_tcon))
+ return tlink;
+
+ /* return error if we tried this already recently */
+ if (time_before(jiffies, tlink->tl_time + TLINK_ERROR_EXPIRE)) {
+ cifs_put_tlink(tlink);
+ return ERR_PTR(-EACCES);
+ }
+
+ if (test_and_set_bit(TCON_LINK_PENDING, &tlink->tl_flags))
+ goto wait_for_construction;
+ }
+
+ tlink->tl_tcon = cifs_construct_tcon(cifs_sb, fsuid);
+ clear_bit(TCON_LINK_PENDING, &tlink->tl_flags);
+ wake_up_bit(&tlink->tl_flags, TCON_LINK_PENDING);
+
+ if (IS_ERR(tlink->tl_tcon)) {
+ cifs_put_tlink(tlink);
+ return ERR_PTR(-EACCES);
+ }
+
+ return tlink;
+}
+
+/*
+ * periodic workqueue job that scans tcon_tree for a superblock and closes
+ * out tcons.
+ */
+static void
+cifs_prune_tlinks(struct work_struct *work)
+{
+ struct cifs_sb_info *cifs_sb = container_of(work, struct cifs_sb_info,
+ prune_tlinks.work);
+ struct rb_root *root = &cifs_sb->tlink_tree;
+ struct rb_node *node;
+ struct rb_node *tmp;
+ struct tcon_link *tlink;
+
+ /*
+ * Because we drop the spinlock in the loop in order to put the tlink
+ * it's not guarded against removal of links from the tree. The only
+ * places that remove entries from the tree are this function and
+ * umounts. Because this function is non-reentrant and is canceled
+ * before umount can proceed, this is safe.
+ */
+ spin_lock(&cifs_sb->tlink_tree_lock);
+ node = rb_first(root);
+ while (node != NULL) {
+ tmp = node;
+ node = rb_next(tmp);
+ tlink = rb_entry(tmp, struct tcon_link, tl_rbnode);
+
+ if (test_bit(TCON_LINK_MASTER, &tlink->tl_flags) ||
+ atomic_read(&tlink->tl_count) != 0 ||
+ time_after(tlink->tl_time + TLINK_IDLE_EXPIRE, jiffies))
+ continue;
+
+ cifs_get_tlink(tlink);
+ clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
+ rb_erase(tmp, root);
+
+ spin_unlock(&cifs_sb->tlink_tree_lock);
+ cifs_put_tlink(tlink);
+ spin_lock(&cifs_sb->tlink_tree_lock);
+ }
+ spin_unlock(&cifs_sb->tlink_tree_lock);
+
+ queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
+ TLINK_IDLE_EXPIRE);
+}
+
+#ifdef CONFIG_CIFS_DFS_UPCALL
+/* Update dfs referral path of superblock */
+static int update_server_fullpath(struct TCP_Server_Info *server, struct cifs_sb_info *cifs_sb,
+ const char *target)
+{
+ int rc = 0;
+ size_t len = strlen(target);
+ char *refpath, *npath;
+
+ if (unlikely(len < 2 || *target != '\\'))
+ return -EINVAL;
+
+ if (target[1] == '\\') {
+ len += 1;
+ refpath = kmalloc(len, GFP_KERNEL);
+ if (!refpath)
+ return -ENOMEM;
+
+ scnprintf(refpath, len, "%s", target);
+ } else {
+ len += sizeof("\\");
+ refpath = kmalloc(len, GFP_KERNEL);
+ if (!refpath)
+ return -ENOMEM;
+
+ scnprintf(refpath, len, "\\%s", target);
+ }
+
+ npath = dfs_cache_canonical_path(refpath, cifs_sb->local_nls, cifs_remap(cifs_sb));
+ kfree(refpath);
+
+ if (IS_ERR(npath)) {
+ rc = PTR_ERR(npath);
+ } else {
+ mutex_lock(&server->refpath_lock);
+ kfree(server->leaf_fullpath);
+ server->leaf_fullpath = npath;
+ mutex_unlock(&server->refpath_lock);
+ server->current_fullpath = server->leaf_fullpath;
+ }
+ return rc;
+}
+
+static int target_share_matches_server(struct TCP_Server_Info *server, const char *tcp_host,
+ size_t tcp_host_len, char *share, bool *target_match)
+{
+ int rc = 0;
+ const char *dfs_host;
+ size_t dfs_host_len;
+
+ *target_match = true;
+ extract_unc_hostname(share, &dfs_host, &dfs_host_len);
+
+ /* Check if hostnames or addresses match */
+ if (dfs_host_len != tcp_host_len || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) {
+ cifs_dbg(FYI, "%s: %.*s doesn't match %.*s\n", __func__, (int)dfs_host_len,
+ dfs_host, (int)tcp_host_len, tcp_host);
+ rc = match_target_ip(server, dfs_host, dfs_host_len, target_match);
+ if (rc)
+ cifs_dbg(VFS, "%s: failed to match target ip: %d\n", __func__, rc);
+ }
+ return rc;
+}
+
+static int __tree_connect_dfs_target(const unsigned int xid, struct cifs_tcon *tcon,
+ struct cifs_sb_info *cifs_sb, char *tree, bool islink,
+ struct dfs_cache_tgt_list *tl)
+{
+ int rc;
+ struct TCP_Server_Info *server = tcon->ses->server;
+ const struct smb_version_operations *ops = server->ops;
+ struct cifs_tcon *ipc = tcon->ses->tcon_ipc;
+ char *share = NULL, *prefix = NULL;
+ const char *tcp_host;
+ size_t tcp_host_len;
+ struct dfs_cache_tgt_iterator *tit;
+ bool target_match;
+
+ extract_unc_hostname(server->hostname, &tcp_host, &tcp_host_len);
+
+ tit = dfs_cache_get_tgt_iterator(tl);
+ if (!tit) {
+ rc = -ENOENT;
+ goto out;
+ }
+
+ /* Try to tree connect to all dfs targets */
+ for (; tit; tit = dfs_cache_get_next_tgt(tl, tit)) {
+ const char *target = dfs_cache_get_tgt_name(tit);
+ struct dfs_cache_tgt_list ntl = DFS_CACHE_TGT_LIST_INIT(ntl);
+
+ kfree(share);
+ kfree(prefix);
+ share = prefix = NULL;
+
+ /* Check if share matches with tcp ses */
+ rc = dfs_cache_get_tgt_share(server->current_fullpath + 1, tit, &share, &prefix);
+ if (rc) {
+ cifs_dbg(VFS, "%s: failed to parse target share: %d\n", __func__, rc);
+ break;
+ }
+
+ rc = target_share_matches_server(server, tcp_host, tcp_host_len, share,
+ &target_match);
+ if (rc)
+ break;
+ if (!target_match) {
+ rc = -EHOSTUNREACH;
+ continue;
+ }
+
+ if (ipc->need_reconnect) {
+ scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", server->hostname);
+ rc = ops->tree_connect(xid, ipc->ses, tree, ipc, cifs_sb->local_nls);
+ if (rc)
+ break;
+ }
+
+ scnprintf(tree, MAX_TREE_SIZE, "\\%s", share);
+ if (!islink) {
+ rc = ops->tree_connect(xid, tcon->ses, tree, tcon, cifs_sb->local_nls);
+ break;
+ }
+ /*
+ * If no dfs referrals were returned from link target, then just do a TREE_CONNECT
+ * to it. Otherwise, cache the dfs referral and then mark current tcp ses for
+ * reconnect so either the demultiplex thread or the echo worker will reconnect to
+ * newly resolved target.
+ */
+ if (dfs_cache_find(xid, tcon->ses, cifs_sb->local_nls, cifs_remap(cifs_sb), target,
+ NULL, &ntl)) {
+ rc = ops->tree_connect(xid, tcon->ses, tree, tcon, cifs_sb->local_nls);
+ if (rc)
+ continue;
+ rc = dfs_cache_noreq_update_tgthint(server->current_fullpath + 1, tit);
+ if (!rc)
+ rc = cifs_update_super_prepath(cifs_sb, prefix);
+ } else {
+ /* Target is another dfs share */
+ rc = update_server_fullpath(server, cifs_sb, target);
+ dfs_cache_free_tgts(tl);
+
+ if (!rc) {
+ rc = -EREMOTE;
+ list_replace_init(&ntl.tl_list, &tl->tl_list);
+ } else
+ dfs_cache_free_tgts(&ntl);
+ }
+ break;
+ }
+
+out:
+ kfree(share);
+ kfree(prefix);
+
+ return rc;
+}
+
+static int tree_connect_dfs_target(const unsigned int xid, struct cifs_tcon *tcon,
+ struct cifs_sb_info *cifs_sb, char *tree, bool islink,
+ struct dfs_cache_tgt_list *tl)
+{
+ int rc;
+ int num_links = 0;
+ struct TCP_Server_Info *server = tcon->ses->server;
+
+ do {
+ rc = __tree_connect_dfs_target(xid, tcon, cifs_sb, tree, islink, tl);
+ if (!rc || rc != -EREMOTE)
+ break;
+ } while (rc = -ELOOP, ++num_links < MAX_NESTED_LINKS);
+ /*
+ * If we couldn't tree connect to any targets from last referral path, then retry from
+ * original referral path.
+ */
+ if (rc && server->current_fullpath != server->origin_fullpath) {
+ server->current_fullpath = server->origin_fullpath;
+ cifs_signal_cifsd_for_reconnect(server, true);
+ }
+
+ dfs_cache_free_tgts(tl);
+ return rc;
+}
+
+int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
+{
+ int rc;
+ struct TCP_Server_Info *server = tcon->ses->server;
+ const struct smb_version_operations *ops = server->ops;
+ struct super_block *sb = NULL;
+ struct cifs_sb_info *cifs_sb;
+ struct dfs_cache_tgt_list tl = DFS_CACHE_TGT_LIST_INIT(tl);
+ char *tree;
+ struct dfs_info3_param ref = {0};
+
+ /* only send once per connect */
+ spin_lock(&tcon->tc_lock);
+ if (tcon->ses->ses_status != SES_GOOD ||
+ (tcon->status != TID_NEW &&
+ tcon->status != TID_NEED_TCON)) {
+ spin_unlock(&tcon->tc_lock);
+ return 0;
+ }
+ tcon->status = TID_IN_TCON;
+ spin_unlock(&tcon->tc_lock);
+
+ tree = kzalloc(MAX_TREE_SIZE, GFP_KERNEL);
+ if (!tree) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ if (tcon->ipc) {
+ scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", server->hostname);
+ rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc);
+ goto out;
+ }
+
+ sb = cifs_get_tcp_super(server);
+ if (IS_ERR(sb)) {
+ rc = PTR_ERR(sb);
+ cifs_dbg(VFS, "%s: could not find superblock: %d\n", __func__, rc);
+ goto out;
+ }
+
+ cifs_sb = CIFS_SB(sb);
+
+ /* If it is not dfs or there was no cached dfs referral, then reconnect to same share */
+ if (!server->current_fullpath ||
+ dfs_cache_noreq_find(server->current_fullpath + 1, &ref, &tl)) {
+ rc = ops->tree_connect(xid, tcon->ses, tcon->tree_name, tcon, cifs_sb->local_nls);
+ goto out;
+ }
+
+ rc = tree_connect_dfs_target(xid, tcon, cifs_sb, tree, ref.server_type == DFS_TYPE_LINK,
+ &tl);
+ free_dfs_info_param(&ref);
+
+out:
+ kfree(tree);
+ cifs_put_tcp_super(sb);
+
+ if (rc) {
+ spin_lock(&tcon->tc_lock);
+ if (tcon->status == TID_IN_TCON)
+ tcon->status = TID_NEED_TCON;
+ spin_unlock(&tcon->tc_lock);
+ } else {
+ spin_lock(&tcon->tc_lock);
+ if (tcon->status == TID_IN_TCON)
+ tcon->status = TID_GOOD;
+ spin_unlock(&tcon->tc_lock);
+ tcon->need_reconnect = false;
+ }
+
+ return rc;
+}
+#else
+int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
+{
+ int rc;
+ const struct smb_version_operations *ops = tcon->ses->server->ops;
+
+ /* only send once per connect */
+ spin_lock(&tcon->tc_lock);
+ if (tcon->ses->ses_status != SES_GOOD ||
+ (tcon->status != TID_NEW &&
+ tcon->status != TID_NEED_TCON)) {
+ spin_unlock(&tcon->tc_lock);
+ return 0;
+ }
+ tcon->status = TID_IN_TCON;
+ spin_unlock(&tcon->tc_lock);
+
+ rc = ops->tree_connect(xid, tcon->ses, tcon->tree_name, tcon, nlsc);
+ if (rc) {
+ spin_lock(&tcon->tc_lock);
+ if (tcon->status == TID_IN_TCON)
+ tcon->status = TID_NEED_TCON;
+ spin_unlock(&tcon->tc_lock);
+ } else {
+ spin_lock(&tcon->tc_lock);
+ if (tcon->status == TID_IN_TCON)
+ tcon->status = TID_GOOD;
+ tcon->need_reconnect = false;
+ spin_unlock(&tcon->tc_lock);
+ }
+
+ return rc;
+}
+#endif