1 files changed, 372 insertions, 0 deletions

diff --git a/fs/smb/client/smb2file.c b/fs/smb/client/smb2file.c
new file mode 100644
index 0000000000..e0ee96d69d
--- /dev/null
+++ b/fs/smb/client/smb2file.c
@@ -0,0 +1,372 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ *
+ *   Copyright (C) International Business Machines  Corp., 2002, 2011
+ *   Author(s): Steve French (sfrench@us.ibm.com),
+ *              Pavel Shilovsky ((pshilovsky@samba.org) 2012
+ *
+ */
+#include <linux/fs.h>
+#include <linux/filelock.h>
+#include <linux/stat.h>
+#include <linux/slab.h>
+#include <linux/pagemap.h>
+#include <asm/div64.h>
+#include "cifsfs.h"
+#include "cifspdu.h"
+#include "cifsglob.h"
+#include "cifsproto.h"
+#include "cifs_debug.h"
+#include "cifs_fs_sb.h"
+#include "cifs_unicode.h"
+#include "fscache.h"
+#include "smb2proto.h"
+#include "smb2status.h"
+
+static struct smb2_symlink_err_rsp *symlink_data(const struct kvec *iov)
+{
+	struct smb2_err_rsp *err = iov->iov_base;
+	struct smb2_symlink_err_rsp *sym = ERR_PTR(-EINVAL);
+	u32 len;
+
+	if (err->ErrorContextCount) {
+		struct smb2_error_context_rsp *p, *end;
+
+		len = (u32)err->ErrorContextCount * (offsetof(struct smb2_error_context_rsp,
+							      ErrorContextData) +
+						     sizeof(struct smb2_symlink_err_rsp));
+		if (le32_to_cpu(err->ByteCount) < len || iov->iov_len < len + sizeof(*err) + 1)
+			return ERR_PTR(-EINVAL);
+
+		p = (struct smb2_error_context_rsp *)err->ErrorData;
+		end = (struct smb2_error_context_rsp *)((u8 *)err + iov->iov_len);
+		do {
+			if (le32_to_cpu(p->ErrorId) == SMB2_ERROR_ID_DEFAULT) {
+				sym = (struct smb2_symlink_err_rsp *)&p->ErrorContextData;
+				break;
+			}
+			cifs_dbg(FYI, "%s: skipping unhandled error context: 0x%x\n",
+				 __func__, le32_to_cpu(p->ErrorId));
+
+			len = ALIGN(le32_to_cpu(p->ErrorDataLength), 8);
+			p = (struct smb2_error_context_rsp *)((u8 *)&p->ErrorContextData + len);
+		} while (p < end);
+	} else if (le32_to_cpu(err->ByteCount) >= sizeof(*sym) &&
+		   iov->iov_len >= SMB2_SYMLINK_STRUCT_SIZE) {
+		sym = (struct smb2_symlink_err_rsp *)err->ErrorData;
+	}
+
+	if (!IS_ERR(sym) && (le32_to_cpu(sym->SymLinkErrorTag) != SYMLINK_ERROR_TAG ||
+			     le32_to_cpu(sym->ReparseTag) != IO_REPARSE_TAG_SYMLINK))
+		sym = ERR_PTR(-EINVAL);
+
+	return sym;
+}
+
+int smb2_parse_symlink_response(struct cifs_sb_info *cifs_sb, const struct kvec *iov, char **path)
+{
+	struct smb2_symlink_err_rsp *sym;
+	unsigned int sub_offs, sub_len;
+	unsigned int print_offs, print_len;
+	char *s;
+
+	if (!cifs_sb || !iov || !iov->iov_base || !iov->iov_len || !path)
+		return -EINVAL;
+
+	sym = symlink_data(iov);
+	if (IS_ERR(sym))
+		return PTR_ERR(sym);
+
+	sub_len = le16_to_cpu(sym->SubstituteNameLength);
+	sub_offs = le16_to_cpu(sym->SubstituteNameOffset);
+	print_len = le16_to_cpu(sym->PrintNameLength);
+	print_offs = le16_to_cpu(sym->PrintNameOffset);
+
+	if (iov->iov_len < SMB2_SYMLINK_STRUCT_SIZE + sub_offs + sub_len ||
+	    iov->iov_len < SMB2_SYMLINK_STRUCT_SIZE + print_offs + print_len)
+		return -EINVAL;
+
+	s = cifs_strndup_from_utf16((char *)sym->PathBuffer + sub_offs, sub_len, true,
+				    cifs_sb->local_nls);
+	if (!s)
+		return -ENOMEM;
+	convert_delimiter(s, '/');
+	cifs_dbg(FYI, "%s: symlink target: %s\n", __func__, s);
+
+	*path = s;
+	return 0;
+}
+
+int smb2_open_file(const unsigned int xid, struct cifs_open_parms *oparms, __u32 *oplock, void *buf)
+{
+	int rc;
+	__le16 *smb2_path;
+	__u8 smb2_oplock;
+	struct cifs_open_info_data *data = buf;
+	struct smb2_file_all_info file_info = {};
+	struct smb2_file_all_info *smb2_data = data ? &file_info : NULL;
+	struct kvec err_iov = {};
+	int err_buftype = CIFS_NO_BUFFER;
+	struct cifs_fid *fid = oparms->fid;
+	struct network_resiliency_req nr_ioctl_req;
+
+	smb2_path = cifs_convert_path_to_utf16(oparms->path, oparms->cifs_sb);
+	if (smb2_path == NULL)
+		return -ENOMEM;
+
+	oparms->desired_access |= FILE_READ_ATTRIBUTES;
+	smb2_oplock = SMB2_OPLOCK_LEVEL_BATCH;
+
+	rc = SMB2_open(xid, oparms, smb2_path, &smb2_oplock, smb2_data, NULL, &err_iov,
+		       &err_buftype);
+	if (rc && data) {
+		struct smb2_hdr *hdr = err_iov.iov_base;
+
+		if (unlikely(!err_iov.iov_base || err_buftype == CIFS_NO_BUFFER))
+			goto out;
+		if (hdr->Status == STATUS_STOPPED_ON_SYMLINK) {
+			rc = smb2_parse_symlink_response(oparms->cifs_sb, &err_iov,
+							 &data->symlink_target);
+			if (!rc) {
+				memset(smb2_data, 0, sizeof(*smb2_data));
+				oparms->create_options |= OPEN_REPARSE_POINT;
+				rc = SMB2_open(xid, oparms, smb2_path, &smb2_oplock, smb2_data,
+					       NULL, NULL, NULL);
+				oparms->create_options &= ~OPEN_REPARSE_POINT;
+			}
+		}
+	}
+
+	if (rc)
+		goto out;
+
+	if (oparms->tcon->use_resilient) {
+		/* default timeout is 0, servers pick default (120 seconds) */
+		nr_ioctl_req.Timeout =
+			cpu_to_le32(oparms->tcon->handle_timeout);
+		nr_ioctl_req.Reserved = 0;
+		rc = SMB2_ioctl(xid, oparms->tcon, fid->persistent_fid,
+			fid->volatile_fid, FSCTL_LMR_REQUEST_RESILIENCY,
+			(char *)&nr_ioctl_req, sizeof(nr_ioctl_req),
+			CIFSMaxBufSize, NULL, NULL /* no return info */);
+		if (rc == -EOPNOTSUPP) {
+			cifs_dbg(VFS,
+			     "resiliency not supported by server, disabling\n");
+			oparms->tcon->use_resilient = false;
+		} else if (rc)
+			cifs_dbg(FYI, "error %d setting resiliency\n", rc);
+
+		rc = 0;
+	}
+
+	if (smb2_data) {
+		/* if open response does not have IndexNumber field - get it */
+		if (smb2_data->IndexNumber == 0) {
+			rc = SMB2_get_srv_num(xid, oparms->tcon,
+				      fid->persistent_fid,
+				      fid->volatile_fid,
+				      &smb2_data->IndexNumber);
+			if (rc) {
+				/*
+				 * let get_inode_info disable server inode
+				 * numbers
+				 */
+				smb2_data->IndexNumber = 0;
+				rc = 0;
+			}
+		}
+		memcpy(&data->fi, smb2_data, sizeof(data->fi));
+	}
+
+	*oplock = smb2_oplock;
+out:
+	free_rsp_buf(err_buftype, err_iov.iov_base);
+	kfree(smb2_path);
+	return rc;
+}
+
+int
+smb2_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
+		  const unsigned int xid)
+{
+	int rc = 0, stored_rc;
+	unsigned int max_num, num = 0, max_buf;
+	struct smb2_lock_element *buf, *cur;
+	struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
+	struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
+	struct cifsLockInfo *li, *tmp;
+	__u64 length = 1 + flock->fl_end - flock->fl_start;
+	struct list_head tmp_llist;
+
+	INIT_LIST_HEAD(&tmp_llist);
+
+	/*
+	 * Accessing maxBuf is racy with cifs_reconnect - need to store value
+	 * and check it before using.
+	 */
+	max_buf = tcon->ses->server->maxBuf;
+	if (max_buf < sizeof(struct smb2_lock_element))
+		return -EINVAL;
+
+	BUILD_BUG_ON(sizeof(struct smb2_lock_element) > PAGE_SIZE);
+	max_buf = min_t(unsigned int, max_buf, PAGE_SIZE);
+	max_num = max_buf / sizeof(struct smb2_lock_element);
+	buf = kcalloc(max_num, sizeof(struct smb2_lock_element), GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	cur = buf;
+
+	cifs_down_write(&cinode->lock_sem);
+	list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
+		if (flock->fl_start > li->offset ||
+		    (flock->fl_start + length) <
+		    (li->offset + li->length))
+			continue;
+		if (current->tgid != li->pid)
+			/*
+			 * flock and OFD lock are associated with an open
+			 * file description, not the process.
+			 */
+			if (!(flock->fl_flags & (FL_FLOCK | FL_OFDLCK)))
+				continue;
+		if (cinode->can_cache_brlcks) {
+			/*
+			 * We can cache brlock requests - simply remove a lock
+			 * from the file's list.
+			 */
+			list_del(&li->llist);
+			cifs_del_lock_waiters(li);
+			kfree(li);
+			continue;
+		}
+		cur->Length = cpu_to_le64(li->length);
+		cur->Offset = cpu_to_le64(li->offset);
+		cur->Flags = cpu_to_le32(SMB2_LOCKFLAG_UNLOCK);
+		/*
+		 * We need to save a lock here to let us add it again to the
+		 * file's list if the unlock range request fails on the server.
+		 */
+		list_move(&li->llist, &tmp_llist);
+		if (++num == max_num) {
+			stored_rc = smb2_lockv(xid, tcon,
+					       cfile->fid.persistent_fid,
+					       cfile->fid.volatile_fid,
+					       current->tgid, num, buf);
+			if (stored_rc) {
+				/*
+				 * We failed on the unlock range request - add
+				 * all locks from the tmp list to the head of
+				 * the file's list.
+				 */
+				cifs_move_llist(&tmp_llist,
+						&cfile->llist->locks);
+				rc = stored_rc;
+			} else
+				/*
+				 * The unlock range request succeed - free the
+				 * tmp list.
+				 */
+				cifs_free_llist(&tmp_llist);
+			cur = buf;
+			num = 0;
+		} else
+			cur++;
+	}
+	if (num) {
+		stored_rc = smb2_lockv(xid, tcon, cfile->fid.persistent_fid,
+				       cfile->fid.volatile_fid, current->tgid,
+				       num, buf);
+		if (stored_rc) {
+			cifs_move_llist(&tmp_llist, &cfile->llist->locks);
+			rc = stored_rc;
+		} else
+			cifs_free_llist(&tmp_llist);
+	}
+	up_write(&cinode->lock_sem);
+
+	kfree(buf);
+	return rc;
+}
+
+static int
+smb2_push_mand_fdlocks(struct cifs_fid_locks *fdlocks, const unsigned int xid,
+		       struct smb2_lock_element *buf, unsigned int max_num)
+{
+	int rc = 0, stored_rc;
+	struct cifsFileInfo *cfile = fdlocks->cfile;
+	struct cifsLockInfo *li;
+	unsigned int num = 0;
+	struct smb2_lock_element *cur = buf;
+	struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
+
+	list_for_each_entry(li, &fdlocks->locks, llist) {
+		cur->Length = cpu_to_le64(li->length);
+		cur->Offset = cpu_to_le64(li->offset);
+		cur->Flags = cpu_to_le32(li->type |
+						SMB2_LOCKFLAG_FAIL_IMMEDIATELY);
+		if (++num == max_num) {
+			stored_rc = smb2_lockv(xid, tcon,
+					       cfile->fid.persistent_fid,
+					       cfile->fid.volatile_fid,
+					       current->tgid, num, buf);
+			if (stored_rc)
+				rc = stored_rc;
+			cur = buf;
+			num = 0;
+		} else
+			cur++;
+	}
+	if (num) {
+		stored_rc = smb2_lockv(xid, tcon,
+				       cfile->fid.persistent_fid,
+				       cfile->fid.volatile_fid,
+				       current->tgid, num, buf);
+		if (stored_rc)
+			rc = stored_rc;
+	}
+
+	return rc;
+}
+
+int
+smb2_push_mandatory_locks(struct cifsFileInfo *cfile)
+{
+	int rc = 0, stored_rc;
+	unsigned int xid;
+	unsigned int max_num, max_buf;
+	struct smb2_lock_element *buf;
+	struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
+	struct cifs_fid_locks *fdlocks;
+
+	xid = get_xid();
+
+	/*
+	 * Accessing maxBuf is racy with cifs_reconnect - need to store value
+	 * and check it for zero before using.
+	 */
+	max_buf = tlink_tcon(cfile->tlink)->ses->server->maxBuf;
+	if (max_buf < sizeof(struct smb2_lock_element)) {
+		free_xid(xid);
+		return -EINVAL;
+	}
+
+	BUILD_BUG_ON(sizeof(struct smb2_lock_element) > PAGE_SIZE);
+	max_buf = min_t(unsigned int, max_buf, PAGE_SIZE);
+	max_num = max_buf / sizeof(struct smb2_lock_element);
+	buf = kcalloc(max_num, sizeof(struct smb2_lock_element), GFP_KERNEL);
+	if (!buf) {
+		free_xid(xid);
+		return -ENOMEM;
+	}
+
+	list_for_each_entry(fdlocks, &cinode->llist, llist) {
+		stored_rc = smb2_push_mand_fdlocks(fdlocks, xid, buf, max_num);
+		if (stored_rc)
+			rc = stored_rc;
+	}
+
+	kfree(buf);
+	free_xid(xid);
+	return rc;
+}