diff options
Diffstat (limited to 'net/core/sock.c')
| -rw-r--r-- | net/core/sock.c | 3534 |
1 files changed, 3534 insertions, 0 deletions
diff --git a/net/core/sock.c b/net/core/sock.c new file mode 100644 index 000000000..79f085df5 --- /dev/null +++ b/net/core/sock.c @@ -0,0 +1,3534 @@ +/* + * INET An implementation of the TCP/IP protocol suite for the LINUX + * operating system. INET is implemented using the BSD Socket + * interface as the means of communication with the user level. + * + * Generic socket support routines. Memory allocators, socket lock/release + * handler for protocols to use and generic option handler. + * + * + * Authors: Ross Biro + * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> + * Florian La Roche, <flla@stud.uni-sb.de> + * Alan Cox, <A.Cox@swansea.ac.uk> + * + * Fixes: + * Alan Cox : Numerous verify_area() problems + * Alan Cox : Connecting on a connecting socket + * now returns an error for tcp. + * Alan Cox : sock->protocol is set correctly. + * and is not sometimes left as 0. + * Alan Cox : connect handles icmp errors on a + * connect properly. Unfortunately there + * is a restart syscall nasty there. I + * can't match BSD without hacking the C + * library. Ideas urgently sought! + * Alan Cox : Disallow bind() to addresses that are + * not ours - especially broadcast ones!! + * Alan Cox : Socket 1024 _IS_ ok for users. (fencepost) + * Alan Cox : sock_wfree/sock_rfree don't destroy sockets, + * instead they leave that for the DESTROY timer. + * Alan Cox : Clean up error flag in accept + * Alan Cox : TCP ack handling is buggy, the DESTROY timer + * was buggy. Put a remove_sock() in the handler + * for memory when we hit 0. Also altered the timer + * code. The ACK stuff can wait and needs major + * TCP layer surgery. + * Alan Cox : Fixed TCP ack bug, removed remove sock + * and fixed timer/inet_bh race. + * Alan Cox : Added zapped flag for TCP + * Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code + * Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb + * Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources + * Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing. + * Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so... + * Rick Sladkey : Relaxed UDP rules for matching packets. + * C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support + * Pauline Middelink : identd support + * Alan Cox : Fixed connect() taking signals I think. + * Alan Cox : SO_LINGER supported + * Alan Cox : Error reporting fixes + * Anonymous : inet_create tidied up (sk->reuse setting) + * Alan Cox : inet sockets don't set sk->type! + * Alan Cox : Split socket option code + * Alan Cox : Callbacks + * Alan Cox : Nagle flag for Charles & Johannes stuff + * Alex : Removed restriction on inet fioctl + * Alan Cox : Splitting INET from NET core + * Alan Cox : Fixed bogus SO_TYPE handling in getsockopt() + * Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code + * Alan Cox : Split IP from generic code + * Alan Cox : New kfree_skbmem() + * Alan Cox : Make SO_DEBUG superuser only. + * Alan Cox : Allow anyone to clear SO_DEBUG + * (compatibility fix) + * Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput. + * Alan Cox : Allocator for a socket is settable. + * Alan Cox : SO_ERROR includes soft errors. + * Alan Cox : Allow NULL arguments on some SO_ opts + * Alan Cox : Generic socket allocation to make hooks + * easier (suggested by Craig Metz). + * Michael Pall : SO_ERROR returns positive errno again + * Steve Whitehouse: Added default destructor to free + * protocol private data. + * Steve Whitehouse: Added various other default routines + * common to several socket families. + * Chris Evans : Call suser() check last on F_SETOWN + * Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER. + * Andi Kleen : Add sock_kmalloc()/sock_kfree_s() + * Andi Kleen : Fix write_space callback + * Chris Evans : Security fixes - signedness again + * Arnaldo C. Melo : cleanups, use skb_queue_purge + * + * To Fix: + * + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <asm/unaligned.h> +#include <linux/capability.h> +#include <linux/errno.h> +#include <linux/errqueue.h> +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/in.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/sched.h> +#include <linux/sched/mm.h> +#include <linux/timer.h> +#include <linux/string.h> +#include <linux/sockios.h> +#include <linux/net.h> +#include <linux/mm.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/poll.h> +#include <linux/tcp.h> +#include <linux/init.h> +#include <linux/highmem.h> +#include <linux/user_namespace.h> +#include <linux/static_key.h> +#include <linux/memcontrol.h> +#include <linux/prefetch.h> + +#include <linux/uaccess.h> + +#include <linux/netdevice.h> +#include <net/protocol.h> +#include <linux/skbuff.h> +#include <net/net_namespace.h> +#include <net/request_sock.h> +#include <net/sock.h> +#include <linux/net_tstamp.h> +#include <net/xfrm.h> +#include <linux/ipsec.h> +#include <net/cls_cgroup.h> +#include <net/netprio_cgroup.h> +#include <linux/sock_diag.h> + +#include <linux/filter.h> +#include <net/sock_reuseport.h> + +#include <trace/events/sock.h> + +#include <net/tcp.h> +#include <net/busy_poll.h> + +static DEFINE_MUTEX(proto_list_mutex); +static LIST_HEAD(proto_list); + +static void sock_inuse_add(struct net *net, int val); + +/** + * sk_ns_capable - General socket capability test + * @sk: Socket to use a capability on or through + * @user_ns: The user namespace of the capability to use + * @cap: The capability to use + * + * Test to see if the opener of the socket had when the socket was + * created and the current process has the capability @cap in the user + * namespace @user_ns. + */ +bool sk_ns_capable(const struct sock *sk, + struct user_namespace *user_ns, int cap) +{ + return file_ns_capable(sk->sk_socket->file, user_ns, cap) && + ns_capable(user_ns, cap); +} +EXPORT_SYMBOL(sk_ns_capable); + +/** + * sk_capable - Socket global capability test + * @sk: Socket to use a capability on or through + * @cap: The global capability to use + * + * Test to see if the opener of the socket had when the socket was + * created and the current process has the capability @cap in all user + * namespaces. + */ +bool sk_capable(const struct sock *sk, int cap) +{ + return sk_ns_capable(sk, &init_user_ns, cap); +} +EXPORT_SYMBOL(sk_capable); + +/** + * sk_net_capable - Network namespace socket capability test + * @sk: Socket to use a capability on or through + * @cap: The capability to use + * + * Test to see if the opener of the socket had when the socket was created + * and the current process has the capability @cap over the network namespace + * the socket is a member of. + */ +bool sk_net_capable(const struct sock *sk, int cap) +{ + return sk_ns_capable(sk, sock_net(sk)->user_ns, cap); +} +EXPORT_SYMBOL(sk_net_capable); + +/* + * Each address family might have different locking rules, so we have + * one slock key per address family and separate keys for internal and + * userspace sockets. + */ +static struct lock_class_key af_family_keys[AF_MAX]; +static struct lock_class_key af_family_kern_keys[AF_MAX]; +static struct lock_class_key af_family_slock_keys[AF_MAX]; +static struct lock_class_key af_family_kern_slock_keys[AF_MAX]; + +/* + * Make lock validator output more readable. (we pre-construct these + * strings build-time, so that runtime initialization of socket + * locks is fast): + */ + +#define _sock_locks(x) \ + x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \ + x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \ + x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \ + x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \ + x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \ + x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \ + x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \ + x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \ + x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \ + x "27" , x "28" , x "AF_CAN" , \ + x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \ + x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \ + x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \ + x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \ + x "AF_QIPCRTR", x "AF_SMC" , x "AF_XDP" , \ + x "AF_MAX" + +static const char *const af_family_key_strings[AF_MAX+1] = { + _sock_locks("sk_lock-") +}; +static const char *const af_family_slock_key_strings[AF_MAX+1] = { + _sock_locks("slock-") +}; +static const char *const af_family_clock_key_strings[AF_MAX+1] = { + _sock_locks("clock-") +}; + +static const char *const af_family_kern_key_strings[AF_MAX+1] = { + _sock_locks("k-sk_lock-") +}; +static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = { + _sock_locks("k-slock-") +}; +static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = { + _sock_locks("k-clock-") +}; +static const char *const af_family_rlock_key_strings[AF_MAX+1] = { + _sock_locks("rlock-") +}; +static const char *const af_family_wlock_key_strings[AF_MAX+1] = { + _sock_locks("wlock-") +}; +static const char *const af_family_elock_key_strings[AF_MAX+1] = { + _sock_locks("elock-") +}; + +/* + * sk_callback_lock and sk queues locking rules are per-address-family, + * so split the lock classes by using a per-AF key: + */ +static struct lock_class_key af_callback_keys[AF_MAX]; +static struct lock_class_key af_rlock_keys[AF_MAX]; +static struct lock_class_key af_wlock_keys[AF_MAX]; +static struct lock_class_key af_elock_keys[AF_MAX]; +static struct lock_class_key af_kern_callback_keys[AF_MAX]; + +/* Run time adjustable parameters. */ +__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; +EXPORT_SYMBOL(sysctl_wmem_max); +__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; +EXPORT_SYMBOL(sysctl_rmem_max); +__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; +__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; + +/* Maximal space eaten by iovec or ancillary data plus some space */ +int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); +EXPORT_SYMBOL(sysctl_optmem_max); + +int sysctl_tstamp_allow_data __read_mostly = 1; + +DEFINE_STATIC_KEY_FALSE(memalloc_socks_key); +EXPORT_SYMBOL_GPL(memalloc_socks_key); + +/** + * sk_set_memalloc - sets %SOCK_MEMALLOC + * @sk: socket to set it on + * + * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. + * It's the responsibility of the admin to adjust min_free_kbytes + * to meet the requirements + */ +void sk_set_memalloc(struct sock *sk) +{ + sock_set_flag(sk, SOCK_MEMALLOC); + sk->sk_allocation |= __GFP_MEMALLOC; + static_branch_inc(&memalloc_socks_key); +} +EXPORT_SYMBOL_GPL(sk_set_memalloc); + +void sk_clear_memalloc(struct sock *sk) +{ + sock_reset_flag(sk, SOCK_MEMALLOC); + sk->sk_allocation &= ~__GFP_MEMALLOC; + static_branch_dec(&memalloc_socks_key); + + /* + * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward + * progress of swapping. SOCK_MEMALLOC may be cleared while + * it has rmem allocations due to the last swapfile being deactivated + * but there is a risk that the socket is unusable due to exceeding + * the rmem limits. Reclaim the reserves and obey rmem limits again. + */ + sk_mem_reclaim(sk); +} +EXPORT_SYMBOL_GPL(sk_clear_memalloc); + +int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) +{ + int ret; + unsigned int noreclaim_flag; + + /* these should have been dropped before queueing */ + BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); + + noreclaim_flag = memalloc_noreclaim_save(); + ret = sk->sk_backlog_rcv(sk, skb); + memalloc_noreclaim_restore(noreclaim_flag); + + return ret; +} +EXPORT_SYMBOL(__sk_backlog_rcv); + +static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen) +{ + struct timeval tv; + + if (optlen < sizeof(tv)) + return -EINVAL; + if (copy_from_user(&tv, optval, sizeof(tv))) + return -EFAULT; + if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) + return -EDOM; + + if (tv.tv_sec < 0) { + static int warned __read_mostly; + + *timeo_p = 0; + if (warned < 10 && net_ratelimit()) { + warned++; + pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", + __func__, current->comm, task_pid_nr(current)); + } + return 0; + } + *timeo_p = MAX_SCHEDULE_TIMEOUT; + if (tv.tv_sec == 0 && tv.tv_usec == 0) + return 0; + if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1)) + *timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP(tv.tv_usec, USEC_PER_SEC / HZ); + return 0; +} + +static void sock_warn_obsolete_bsdism(const char *name) +{ + static int warned; + static char warncomm[TASK_COMM_LEN]; + if (strcmp(warncomm, current->comm) && warned < 5) { + strcpy(warncomm, current->comm); + pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n", + warncomm, name); + warned++; + } +} + +static bool sock_needs_netstamp(const struct sock *sk) +{ + switch (sk->sk_family) { + case AF_UNSPEC: + case AF_UNIX: + return false; + default: + return true; + } +} + +static void sock_disable_timestamp(struct sock *sk, unsigned long flags) +{ + if (sk->sk_flags & flags) { + sk->sk_flags &= ~flags; + if (sock_needs_netstamp(sk) && + !(sk->sk_flags & SK_FLAGS_TIMESTAMP)) + net_disable_timestamp(); + } +} + + +int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) +{ + unsigned long flags; + struct sk_buff_head *list = &sk->sk_receive_queue; + + if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { + atomic_inc(&sk->sk_drops); + trace_sock_rcvqueue_full(sk, skb); + return -ENOMEM; + } + + if (!sk_rmem_schedule(sk, skb, skb->truesize)) { + atomic_inc(&sk->sk_drops); + return -ENOBUFS; + } + + skb->dev = NULL; + skb_set_owner_r(skb, sk); + + /* we escape from rcu protected region, make sure we dont leak + * a norefcounted dst + */ + skb_dst_force(skb); + + spin_lock_irqsave(&list->lock, flags); + sock_skb_set_dropcount(sk, skb); + __skb_queue_tail(list, skb); + spin_unlock_irqrestore(&list->lock, flags); + + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_data_ready(sk); + return 0; +} +EXPORT_SYMBOL(__sock_queue_rcv_skb); + +int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) +{ + int err; + + err = sk_filter(sk, skb); + if (err) + return err; + + return __sock_queue_rcv_skb(sk, skb); +} +EXPORT_SYMBOL(sock_queue_rcv_skb); + +int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, + const int nested, unsigned int trim_cap, bool refcounted) +{ + int rc = NET_RX_SUCCESS; + + if (sk_filter_trim_cap(sk, skb, trim_cap)) + goto discard_and_relse; + + skb->dev = NULL; + + if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { + atomic_inc(&sk->sk_drops); + goto discard_and_relse; + } + if (nested) + bh_lock_sock_nested(sk); + else + bh_lock_sock(sk); + if (!sock_owned_by_user(sk)) { + /* + * trylock + unlock semantics: + */ + mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); + + rc = sk_backlog_rcv(sk, skb); + + mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); + } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { + bh_unlock_sock(sk); + atomic_inc(&sk->sk_drops); + goto discard_and_relse; + } + + bh_unlock_sock(sk); +out: + if (refcounted) + sock_put(sk); + return rc; +discard_and_relse: + kfree_skb(skb); + goto out; +} +EXPORT_SYMBOL(__sk_receive_skb); + +struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) +{ + struct dst_entry *dst = __sk_dst_get(sk); + + if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { + sk_tx_queue_clear(sk); + sk->sk_dst_pending_confirm = 0; + RCU_INIT_POINTER(sk->sk_dst_cache, NULL); + dst_release(dst); + return NULL; + } + + return dst; +} +EXPORT_SYMBOL(__sk_dst_check); + +struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) +{ + struct dst_entry *dst = sk_dst_get(sk); + + if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { + sk_dst_reset(sk); + dst_release(dst); + return NULL; + } + + return dst; +} +EXPORT_SYMBOL(sk_dst_check); + +static int sock_setbindtodevice(struct sock *sk, char __user *optval, + int optlen) +{ + int ret = -ENOPROTOOPT; +#ifdef CONFIG_NETDEVICES + struct net *net = sock_net(sk); + char devname[IFNAMSIZ]; + int index; + + /* Sorry... */ + ret = -EPERM; + if (!ns_capable(net->user_ns, CAP_NET_RAW)) + goto out; + + ret = -EINVAL; + if (optlen < 0) + goto out; + + /* Bind this socket to a particular device like "eth0", + * as specified in the passed interface name. If the + * name is "" or the option length is zero the socket + * is not bound. + */ + if (optlen > IFNAMSIZ - 1) + optlen = IFNAMSIZ - 1; + memset(devname, 0, sizeof(devname)); + + ret = -EFAULT; + if (copy_from_user(devname, optval, optlen)) + goto out; + + index = 0; + if (devname[0] != '\0') { + struct net_device *dev; + + rcu_read_lock(); + dev = dev_get_by_name_rcu(net, devname); + if (dev) + index = dev->ifindex; + rcu_read_unlock(); + ret = -ENODEV; + if (!dev) + goto out; + } + + lock_sock(sk); + sk->sk_bound_dev_if = index; + sk_dst_reset(sk); + release_sock(sk); + + ret = 0; + +out: +#endif + + return ret; +} + +static int sock_getbindtodevice(struct sock *sk, char __user *optval, + int __user *optlen, int len) +{ + int ret = -ENOPROTOOPT; +#ifdef CONFIG_NETDEVICES + struct net *net = sock_net(sk); + char devname[IFNAMSIZ]; + + if (sk->sk_bound_dev_if == 0) { + len = 0; + goto zero; + } + + ret = -EINVAL; + if (len < IFNAMSIZ) + goto out; + + ret = netdev_get_name(net, devname, sk->sk_bound_dev_if); + if (ret) + goto out; + + len = strlen(devname) + 1; + + ret = -EFAULT; + if (copy_to_user(optval, devname, len)) + goto out; + +zero: + ret = -EFAULT; + if (put_user(len, optlen)) + goto out; + + ret = 0; + +out: +#endif + + return ret; +} + +static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool) +{ + if (valbool) + sock_set_flag(sk, bit); + else + sock_reset_flag(sk, bit); +} + +bool sk_mc_loop(struct sock *sk) +{ + if (dev_recursion_level()) + return false; + if (!sk) + return true; + switch (sk->sk_family) { + case AF_INET: + return inet_sk(sk)->mc_loop; +#if IS_ENABLED(CONFIG_IPV6) + case AF_INET6: + return inet6_sk(sk)->mc_loop; +#endif + } + WARN_ON_ONCE(1); + return true; +} +EXPORT_SYMBOL(sk_mc_loop); + +/* + * This is meant for all protocols to use and covers goings on + * at the socket level. Everything here is generic. + */ + +int sock_setsockopt(struct socket *sock, int level, int optname, + char __user *optval, unsigned int optlen) +{ + struct sock_txtime sk_txtime; + struct sock *sk = sock->sk; + int val; + int valbool; + struct linger ling; + int ret = 0; + + /* + * Options without arguments + */ + + if (optname == SO_BINDTODEVICE) + return sock_setbindtodevice(sk, optval, optlen); + + if (optlen < sizeof(int)) + return -EINVAL; + + if (get_user(val, (int __user *)optval)) + return -EFAULT; + + valbool = val ? 1 : 0; + + lock_sock(sk); + + switch (optname) { + case SO_DEBUG: + if (val && !capable(CAP_NET_ADMIN)) + ret = -EACCES; + else + sock_valbool_flag(sk, SOCK_DBG, valbool); + break; + case SO_REUSEADDR: + sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); + break; + case SO_REUSEPORT: + sk->sk_reuseport = valbool; + break; + case SO_TYPE: + case SO_PROTOCOL: + case SO_DOMAIN: + case SO_ERROR: + ret = -ENOPROTOOPT; + break; + case SO_DONTROUTE: + sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); + sk_dst_reset(sk); + break; + case SO_BROADCAST: + sock_valbool_flag(sk, SOCK_BROADCAST, valbool); + break; + case SO_SNDBUF: + /* Don't error on this BSD doesn't and if you think + * about it this is right. Otherwise apps have to + * play 'guess the biggest size' games. RCVBUF/SNDBUF + * are treated in BSD as hints + */ + val = min_t(u32, val, sysctl_wmem_max); +set_sndbuf: + sk->sk_userlocks |= SOCK_SNDBUF_LOCK; + sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF); + /* Wake up sending tasks if we upped the value. */ + sk->sk_write_space(sk); + break; + + case SO_SNDBUFFORCE: + if (!capable(CAP_NET_ADMIN)) { + ret = -EPERM; + break; + } + goto set_sndbuf; + + case SO_RCVBUF: + /* Don't error on this BSD doesn't and if you think + * about it this is right. Otherwise apps have to + * play 'guess the biggest size' games. RCVBUF/SNDBUF + * are treated in BSD as hints + */ + val = min_t(u32, val, sysctl_rmem_max); +set_rcvbuf: + sk->sk_userlocks |= SOCK_RCVBUF_LOCK; + /* + * We double it on the way in to account for + * "struct sk_buff" etc. overhead. Applications + * assume that the SO_RCVBUF setting they make will + * allow that much actual data to be received on that + * socket. + * + * Applications are unaware that "struct sk_buff" and + * other overheads allocate from the receive buffer + * during socket buffer allocation. + * + * And after considering the possible alternatives, + * returning the value we actually used in getsockopt + * is the most desirable behavior. + */ + sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF); + break; + + case SO_RCVBUFFORCE: + if (!capable(CAP_NET_ADMIN)) { + ret = -EPERM; + break; + } + goto set_rcvbuf; + + case SO_KEEPALIVE: + if (sk->sk_prot->keepalive) + sk->sk_prot->keepalive(sk, valbool); + sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); + break; + + case SO_OOBINLINE: + sock_valbool_flag(sk, SOCK_URGINLINE, valbool); + break; + + case SO_NO_CHECK: + sk->sk_no_check_tx = valbool; + break; + + case SO_PRIORITY: + if ((val >= 0 && val <= 6) || + ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) + sk->sk_priority = val; + else + ret = -EPERM; + break; + + case SO_LINGER: + if (optlen < sizeof(ling)) { + ret = -EINVAL; /* 1003.1g */ + break; + } + if (copy_from_user(&ling, optval, sizeof(ling))) { + ret = -EFAULT; + break; + } + if (!ling.l_onoff) + sock_reset_flag(sk, SOCK_LINGER); + else { +#if (BITS_PER_LONG == 32) + if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) + sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; + else +#endif + sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; + sock_set_flag(sk, SOCK_LINGER); + } + break; + + case SO_BSDCOMPAT: + sock_warn_obsolete_bsdism("setsockopt"); + break; + + case SO_PASSCRED: + if (valbool) + set_bit(SOCK_PASSCRED, &sock->flags); + else + clear_bit(SOCK_PASSCRED, &sock->flags); + break; + + case SO_TIMESTAMP: + case SO_TIMESTAMPNS: + if (valbool) { + if (optname == SO_TIMESTAMP) + sock_reset_flag(sk, SOCK_RCVTSTAMPNS); + else + sock_set_flag(sk, SOCK_RCVTSTAMPNS); + sock_set_flag(sk, SOCK_RCVTSTAMP); + sock_enable_timestamp(sk, SOCK_TIMESTAMP); + } else { + sock_reset_flag(sk, SOCK_RCVTSTAMP); + sock_reset_flag(sk, SOCK_RCVTSTAMPNS); + } + break; + + case SO_TIMESTAMPING: + if (val & ~SOF_TIMESTAMPING_MASK) { + ret = -EINVAL; + break; + } + + if (val & SOF_TIMESTAMPING_OPT_ID && + !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) { + if (sk->sk_protocol == IPPROTO_TCP && + sk->sk_type == SOCK_STREAM) { + if ((1 << sk->sk_state) & + (TCPF_CLOSE | TCPF_LISTEN)) { + ret = -EINVAL; + break; + } + sk->sk_tskey = tcp_sk(sk)->snd_una; + } else { + sk->sk_tskey = 0; + } + } + + if (val & SOF_TIMESTAMPING_OPT_STATS && + !(val & SOF_TIMESTAMPING_OPT_TSONLY)) { + ret = -EINVAL; + break; + } + + sk->sk_tsflags = val; + if (val & SOF_TIMESTAMPING_RX_SOFTWARE) + sock_enable_timestamp(sk, + SOCK_TIMESTAMPING_RX_SOFTWARE); + else + sock_disable_timestamp(sk, + (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); + break; + + case SO_RCVLOWAT: + if (val < 0) + val = INT_MAX; + if (sock->ops->set_rcvlowat) + ret = sock->ops->set_rcvlowat(sk, val); + else + sk->sk_rcvlowat = val ? : 1; + break; + + case SO_RCVTIMEO: + ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen); + break; + + case SO_SNDTIMEO: + ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen); + break; + + case SO_ATTACH_FILTER: + ret = -EINVAL; + if (optlen == sizeof(struct sock_fprog)) { + struct sock_fprog fprog; + + ret = -EFAULT; + if (copy_from_user(&fprog, optval, sizeof(fprog))) + break; + + ret = sk_attach_filter(&fprog, sk); + } + break; + + case SO_ATTACH_BPF: + ret = -EINVAL; + if (optlen == sizeof(u32)) { + u32 ufd; + + ret = -EFAULT; + if (copy_from_user(&ufd, optval, sizeof(ufd))) + break; + + ret = sk_attach_bpf(ufd, sk); + } + break; + + case SO_ATTACH_REUSEPORT_CBPF: + ret = -EINVAL; + if (optlen == sizeof(struct sock_fprog)) { + struct sock_fprog fprog; + + ret = -EFAULT; + if (copy_from_user(&fprog, optval, sizeof(fprog))) + break; + + ret = sk_reuseport_attach_filter(&fprog, sk); + } + break; + + case SO_ATTACH_REUSEPORT_EBPF: + ret = -EINVAL; + if (optlen == sizeof(u32)) { + u32 ufd; + + ret = -EFAULT; + if (copy_from_user(&ufd, optval, sizeof(ufd))) + break; + + ret = sk_reuseport_attach_bpf(ufd, sk); + } + break; + + case SO_DETACH_FILTER: + ret = sk_detach_filter(sk); + break; + + case SO_LOCK_FILTER: + if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) + ret = -EPERM; + else + sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); + break; + + case SO_PASSSEC: + if (valbool) + set_bit(SOCK_PASSSEC, &sock->flags); + else + clear_bit(SOCK_PASSSEC, &sock->flags); + break; + case SO_MARK: + if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) + ret = -EPERM; + else + sk->sk_mark = val; + break; + + case SO_RXQ_OVFL: + sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); + break; + + case SO_WIFI_STATUS: + sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); + break; + + case SO_PEEK_OFF: + if (sock->ops->set_peek_off) + ret = sock->ops->set_peek_off(sk, val); + else + ret = -EOPNOTSUPP; + break; + + case SO_NOFCS: + sock_valbool_flag(sk, SOCK_NOFCS, valbool); + break; + + case SO_SELECT_ERR_QUEUE: + sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); + break; + +#ifdef CONFIG_NET_RX_BUSY_POLL + case SO_BUSY_POLL: + /* allow unprivileged users to decrease the value */ + if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN)) + ret = -EPERM; + else { + if (val < 0) + ret = -EINVAL; + else + WRITE_ONCE(sk->sk_ll_usec, val); + } + break; +#endif + + case SO_MAX_PACING_RATE: + if (val != ~0U) + cmpxchg(&sk->sk_pacing_status, + SK_PACING_NONE, + SK_PACING_NEEDED); + sk->sk_max_pacing_rate = val; + sk->sk_pacing_rate = min(sk->sk_pacing_rate, + sk->sk_max_pacing_rate); + break; + + case SO_INCOMING_CPU: + WRITE_ONCE(sk->sk_incoming_cpu, val); + break; + + case SO_CNX_ADVICE: + if (val == 1) + dst_negative_advice(sk); + break; + + case SO_ZEROCOPY: + if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) { + if (sk->sk_protocol != IPPROTO_TCP) + ret = -ENOTSUPP; + } else if (sk->sk_family != PF_RDS) { + ret = -ENOTSUPP; + } + if (!ret) { + if (val < 0 || val > 1) + ret = -EINVAL; + else + sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool); + } + break; + + case SO_TXTIME: + if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { + ret = -EPERM; + } else if (optlen != sizeof(struct sock_txtime)) { + ret = -EINVAL; + } else if (copy_from_user(&sk_txtime, optval, + sizeof(struct sock_txtime))) { + ret = -EFAULT; + } else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) { + ret = -EINVAL; + } else { + sock_valbool_flag(sk, SOCK_TXTIME, true); + sk->sk_clockid = sk_txtime.clockid; + sk->sk_txtime_deadline_mode = + !!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE); + sk->sk_txtime_report_errors = + !!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS); + } + break; + + default: + ret = -ENOPROTOOPT; + break; + } + release_sock(sk); + return ret; +} +EXPORT_SYMBOL(sock_setsockopt); + +static const struct cred *sk_get_peer_cred(struct sock *sk) +{ + const struct cred *cred; + + spin_lock(&sk->sk_peer_lock); + cred = get_cred(sk->sk_peer_cred); + spin_unlock(&sk->sk_peer_lock); + + return cred; +} + +static void cred_to_ucred(struct pid *pid, const struct cred *cred, + struct ucred *ucred) +{ + ucred->pid = pid_vnr(pid); + ucred->uid = ucred->gid = -1; + if (cred) { + struct user_namespace *current_ns = current_user_ns(); + + ucred->uid = from_kuid_munged(current_ns, cred->euid); + ucred->gid = from_kgid_munged(current_ns, cred->egid); + } +} + +static int groups_to_user(gid_t __user *dst, const struct group_info *src) +{ + struct user_namespace *user_ns = current_user_ns(); + int i; + + for (i = 0; i < src->ngroups; i++) + if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i)) + return -EFAULT; + + return 0; +} + +int sock_getsockopt(struct socket *sock, int level, int optname, + char __user *optval, int __user *optlen) +{ + struct sock *sk = sock->sk; + + union { + int val; + u64 val64; + struct linger ling; + struct timeval tm; + struct sock_txtime txtime; + } v; + + int lv = sizeof(int); + int len; + + if (get_user(len, optlen)) + return -EFAULT; + if (len < 0) + return -EINVAL; + + memset(&v, 0, sizeof(v)); + + switch (optname) { + case SO_DEBUG: + v.val = sock_flag(sk, SOCK_DBG); + break; + + case SO_DONTROUTE: + v.val = sock_flag(sk, SOCK_LOCALROUTE); + break; + + case SO_BROADCAST: + v.val = sock_flag(sk, SOCK_BROADCAST); + break; + + case SO_SNDBUF: + v.val = sk->sk_sndbuf; + break; + + case SO_RCVBUF: + v.val = sk->sk_rcvbuf; + break; + + case SO_REUSEADDR: + v.val = sk->sk_reuse; + break; + + case SO_REUSEPORT: + v.val = sk->sk_reuseport; + break; + + case SO_KEEPALIVE: + v.val = sock_flag(sk, SOCK_KEEPOPEN); + break; + + case SO_TYPE: + v.val = sk->sk_type; + break; + + case SO_PROTOCOL: + v.val = sk->sk_protocol; + break; + + case SO_DOMAIN: + v.val = sk->sk_family; + break; + + case SO_ERROR: + v.val = -sock_error(sk); + if (v.val == 0) + v.val = xchg(&sk->sk_err_soft, 0); + break; + + case SO_OOBINLINE: + v.val = sock_flag(sk, SOCK_URGINLINE); + break; + + case SO_NO_CHECK: + v.val = sk->sk_no_check_tx; + break; + + case SO_PRIORITY: + v.val = sk->sk_priority; + break; + + case SO_LINGER: + lv = sizeof(v.ling); + v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); + v.ling.l_linger = sk->sk_lingertime / HZ; + break; + + case SO_BSDCOMPAT: + sock_warn_obsolete_bsdism("getsockopt"); + break; + + case SO_TIMESTAMP: + v.val = sock_flag(sk, SOCK_RCVTSTAMP) && + !sock_flag(sk, SOCK_RCVTSTAMPNS); + break; + + case SO_TIMESTAMPNS: + v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); + break; + + case SO_TIMESTAMPING: + v.val = sk->sk_tsflags; + break; + + case SO_RCVTIMEO: + lv = sizeof(struct timeval); + if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { + v.tm.tv_sec = 0; + v.tm.tv_usec = 0; + } else { + v.tm.tv_sec = sk->sk_rcvtimeo / HZ; + v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * USEC_PER_SEC) / HZ; + } + break; + + case SO_SNDTIMEO: + lv = sizeof(struct timeval); + if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { + v.tm.tv_sec = 0; + v.tm.tv_usec = 0; + } else { + v.tm.tv_sec = sk->sk_sndtimeo / HZ; + v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * USEC_PER_SEC) / HZ; + } + break; + + case SO_RCVLOWAT: + v.val = sk->sk_rcvlowat; + break; + + case SO_SNDLOWAT: + v.val = 1; + break; + + case SO_PASSCRED: + v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); + break; + + case SO_PEERCRED: + { + struct ucred peercred; + if (len > sizeof(peercred)) + len = sizeof(peercred); + + spin_lock(&sk->sk_peer_lock); + cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); + spin_unlock(&sk->sk_peer_lock); + + if (copy_to_user(optval, &peercred, len)) + return -EFAULT; + goto lenout; + } + + case SO_PEERGROUPS: + { + const struct cred *cred; + int ret, n; + + cred = sk_get_peer_cred(sk); + if (!cred) + return -ENODATA; + + n = cred->group_info->ngroups; + if (len < n * sizeof(gid_t)) { + len = n * sizeof(gid_t); + put_cred(cred); + return put_user(len, optlen) ? -EFAULT : -ERANGE; + } + len = n * sizeof(gid_t); + + ret = groups_to_user((gid_t __user *)optval, cred->group_info); + put_cred(cred); + if (ret) + return ret; + goto lenout; + } + + case SO_PEERNAME: + { + char address[128]; + + lv = sock->ops->getname(sock, (struct sockaddr *)address, 2); + if (lv < 0) + return -ENOTCONN; + if (lv < len) + return -EINVAL; + if (copy_to_user(optval, address, len)) + return -EFAULT; + goto lenout; + } + + /* Dubious BSD thing... Probably nobody even uses it, but + * the UNIX standard wants it for whatever reason... -DaveM + */ + case SO_ACCEPTCONN: + v.val = sk->sk_state == TCP_LISTEN; + break; + + case SO_PASSSEC: + v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); + break; + + case SO_PEERSEC: + return security_socket_getpeersec_stream(sock, optval, optlen, len); + + case SO_MARK: + v.val = sk->sk_mark; + break; + + case SO_RXQ_OVFL: + v.val = sock_flag(sk, SOCK_RXQ_OVFL); + break; + + case SO_WIFI_STATUS: + v.val = sock_flag(sk, SOCK_WIFI_STATUS); + break; + + case SO_PEEK_OFF: + if (!sock->ops->set_peek_off) + return -EOPNOTSUPP; + + v.val = sk->sk_peek_off; + break; + case SO_NOFCS: + v.val = sock_flag(sk, SOCK_NOFCS); + break; + + case SO_BINDTODEVICE: + return sock_getbindtodevice(sk, optval, optlen, len); + + case SO_GET_FILTER: + len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); + if (len < 0) + return len; + + goto lenout; + + case SO_LOCK_FILTER: + v.val = sock_flag(sk, SOCK_FILTER_LOCKED); + break; + + case SO_BPF_EXTENSIONS: + v.val = bpf_tell_extensions(); + break; + + case SO_SELECT_ERR_QUEUE: + v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); + break; + +#ifdef CONFIG_NET_RX_BUSY_POLL + case SO_BUSY_POLL: + v.val = sk->sk_ll_usec; + break; +#endif + + case SO_MAX_PACING_RATE: + v.val = sk->sk_max_pacing_rate; + break; + + case SO_INCOMING_CPU: + v.val = READ_ONCE(sk->sk_incoming_cpu); + break; + + case SO_MEMINFO: + { + u32 meminfo[SK_MEMINFO_VARS]; + + sk_get_meminfo(sk, meminfo); + + len = min_t(unsigned int, len, sizeof(meminfo)); + if (copy_to_user(optval, &meminfo, len)) + return -EFAULT; + + goto lenout; + } + +#ifdef CONFIG_NET_RX_BUSY_POLL + case SO_INCOMING_NAPI_ID: + v.val = READ_ONCE(sk->sk_napi_id); + + /* aggregate non-NAPI IDs down to 0 */ + if (v.val < MIN_NAPI_ID) + v.val = 0; + + break; +#endif + + case SO_COOKIE: + lv = sizeof(u64); + if (len < lv) + return -EINVAL; + v.val64 = sock_gen_cookie(sk); + break; + + case SO_ZEROCOPY: + v.val = sock_flag(sk, SOCK_ZEROCOPY); + break; + + case SO_TXTIME: + lv = sizeof(v.txtime); + v.txtime.clockid = sk->sk_clockid; + v.txtime.flags |= sk->sk_txtime_deadline_mode ? + SOF_TXTIME_DEADLINE_MODE : 0; + v.txtime.flags |= sk->sk_txtime_report_errors ? + SOF_TXTIME_REPORT_ERRORS : 0; + break; + + default: + /* We implement the SO_SNDLOWAT etc to not be settable + * (1003.1g 7). + */ + return -ENOPROTOOPT; + } + + if (len > lv) + len = lv; + if (copy_to_user(optval, &v, len)) + return -EFAULT; +lenout: + if (put_user(len, optlen)) + return -EFAULT; + return 0; +} + +/* + * Initialize an sk_lock. + * + * (We also register the sk_lock with the lock validator.) + */ +static inline void sock_lock_init(struct sock *sk) +{ + if (sk->sk_kern_sock) + sock_lock_init_class_and_name( + sk, + af_family_kern_slock_key_strings[sk->sk_family], + af_family_kern_slock_keys + sk->sk_family, + af_family_kern_key_strings[sk->sk_family], + af_family_kern_keys + sk->sk_family); + else + sock_lock_init_class_and_name( + sk, + af_family_slock_key_strings[sk->sk_family], + af_family_slock_keys + sk->sk_family, + af_family_key_strings[sk->sk_family], + af_family_keys + sk->sk_family); +} + +/* + * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, + * even temporarly, because of RCU lookups. sk_node should also be left as is. + * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end + */ +static void sock_copy(struct sock *nsk, const struct sock *osk) +{ +#ifdef CONFIG_SECURITY_NETWORK + void *sptr = nsk->sk_security; +#endif + memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); + + memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, + osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); + +#ifdef CONFIG_SECURITY_NETWORK + nsk->sk_security = sptr; + security_sk_clone(osk, nsk); +#endif +} + +static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, + int family) +{ + struct sock *sk; + struct kmem_cache *slab; + + slab = prot->slab; + if (slab != NULL) { + sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); + if (!sk) + return sk; + if (priority & __GFP_ZERO) + sk_prot_clear_nulls(sk, prot->obj_size); + } else + sk = kmalloc(prot->obj_size, priority); + + if (sk != NULL) { + if (security_sk_alloc(sk, family, priority)) + goto out_free; + + if (!try_module_get(prot->owner)) + goto out_free_sec; + sk_tx_queue_clear(sk); + } + + return sk; + +out_free_sec: + security_sk_free(sk); +out_free: + if (slab != NULL) + kmem_cache_free(slab, sk); + else + kfree(sk); + return NULL; +} + +static void sk_prot_free(struct proto *prot, struct sock *sk) +{ + struct kmem_cache *slab; + struct module *owner; + + owner = prot->owner; + slab = prot->slab; + + cgroup_sk_free(&sk->sk_cgrp_data); + mem_cgroup_sk_free(sk); + security_sk_free(sk); + if (slab != NULL) + kmem_cache_free(slab, sk); + else + kfree(sk); + module_put(owner); +} + +/** + * sk_alloc - All socket objects are allocated here + * @net: the applicable net namespace + * @family: protocol family + * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) + * @prot: struct proto associated with this new sock instance + * @kern: is this to be a kernel socket? + */ +struct sock *sk_alloc(struct net *net, int family, gfp_t priority, + struct proto *prot, int kern) +{ + struct sock *sk; + + sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); + if (sk) { + sk->sk_family = family; + /* + * See comment in struct sock definition to understand + * why we need sk_prot_creator -acme + */ + sk->sk_prot = sk->sk_prot_creator = prot; + sk->sk_kern_sock = kern; + sock_lock_init(sk); + sk->sk_net_refcnt = kern ? 0 : 1; + if (likely(sk->sk_net_refcnt)) { + get_net(net); + sock_inuse_add(net, 1); + } + + sock_net_set(sk, net); + refcount_set(&sk->sk_wmem_alloc, 1); + + mem_cgroup_sk_alloc(sk); + cgroup_sk_alloc(&sk->sk_cgrp_data); + sock_update_classid(&sk->sk_cgrp_data); + sock_update_netprioidx(&sk->sk_cgrp_data); + sk_tx_queue_clear(sk); + } + + return sk; +} +EXPORT_SYMBOL(sk_alloc); + +/* Sockets having SOCK_RCU_FREE will call this function after one RCU + * grace period. This is the case for UDP sockets and TCP listeners. + */ +static void __sk_destruct(struct rcu_head *head) +{ + struct sock *sk = container_of(head, struct sock, sk_rcu); + struct sk_filter *filter; + + if (sk->sk_destruct) + sk->sk_destruct(sk); + + filter = rcu_dereference_check(sk->sk_filter, + refcount_read(&sk->sk_wmem_alloc) == 0); + if (filter) { + sk_filter_uncharge(sk, filter); + RCU_INIT_POINTER(sk->sk_filter, NULL); + } + + sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); + + if (atomic_read(&sk->sk_omem_alloc)) + pr_debug("%s: optmem leakage (%d bytes) detected\n", + __func__, atomic_read(&sk->sk_omem_alloc)); + + if (sk->sk_frag.page) { + put_page(sk->sk_frag.page); + sk->sk_frag.page = NULL; + } + + /* We do not need to acquire sk->sk_peer_lock, we are the last user. */ + put_cred(sk->sk_peer_cred); + put_pid(sk->sk_peer_pid); + + if (likely(sk->sk_net_refcnt)) + put_net(sock_net(sk)); + sk_prot_free(sk->sk_prot_creator, sk); +} + +void sk_destruct(struct sock *sk) +{ + bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE); + + if (rcu_access_pointer(sk->sk_reuseport_cb)) { + reuseport_detach_sock(sk); + use_call_rcu = true; + } + + if (use_call_rcu) + call_rcu(&sk->sk_rcu, __sk_destruct); + else + __sk_destruct(&sk->sk_rcu); +} + +static void __sk_free(struct sock *sk) +{ + if (likely(sk->sk_net_refcnt)) + sock_inuse_add(sock_net(sk), -1); + + if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk))) + sock_diag_broadcast_destroy(sk); + else + sk_destruct(sk); +} + +void sk_free(struct sock *sk) +{ + /* + * We subtract one from sk_wmem_alloc and can know if + * some packets are still in some tx queue. + * If not null, sock_wfree() will call __sk_free(sk) later + */ + if (refcount_dec_and_test(&sk->sk_wmem_alloc)) + __sk_free(sk); +} +EXPORT_SYMBOL(sk_free); + +static void sk_init_common(struct sock *sk) +{ + skb_queue_head_init(&sk->sk_receive_queue); + skb_queue_head_init(&sk->sk_write_queue); + skb_queue_head_init(&sk->sk_error_queue); + + rwlock_init(&sk->sk_callback_lock); + lockdep_set_class_and_name(&sk->sk_receive_queue.lock, + af_rlock_keys + sk->sk_family, + af_family_rlock_key_strings[sk->sk_family]); + lockdep_set_class_and_name(&sk->sk_write_queue.lock, + af_wlock_keys + sk->sk_family, + af_family_wlock_key_strings[sk->sk_family]); + lockdep_set_class_and_name(&sk->sk_error_queue.lock, + af_elock_keys + sk->sk_family, + af_family_elock_key_strings[sk->sk_family]); + lockdep_set_class_and_name(&sk->sk_callback_lock, + af_callback_keys + sk->sk_family, + af_family_clock_key_strings[sk->sk_family]); +} + +/** + * sk_clone_lock - clone a socket, and lock its clone + * @sk: the socket to clone + * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) + * + * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) + */ +struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) +{ + struct sock *newsk; + bool is_charged = true; + + newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); + if (newsk != NULL) { + struct sk_filter *filter; + + sock_copy(newsk, sk); + + newsk->sk_prot_creator = sk->sk_prot; + + /* SANITY */ + if (likely(newsk->sk_net_refcnt)) + get_net(sock_net(newsk)); + sk_node_init(&newsk->sk_node); + sock_lock_init(newsk); + bh_lock_sock(newsk); + newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; + newsk->sk_backlog.len = 0; + + atomic_set(&newsk->sk_rmem_alloc, 0); + /* + * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) + */ + refcount_set(&newsk->sk_wmem_alloc, 1); + atomic_set(&newsk->sk_omem_alloc, 0); + sk_init_common(newsk); + + newsk->sk_dst_cache = NULL; + newsk->sk_dst_pending_confirm = 0; + newsk->sk_wmem_queued = 0; + newsk->sk_forward_alloc = 0; + atomic_set(&newsk->sk_drops, 0); + newsk->sk_send_head = NULL; + newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; + atomic_set(&newsk->sk_zckey, 0); + + sock_reset_flag(newsk, SOCK_DONE); + + /* sk->sk_memcg will be populated at accept() time */ + newsk->sk_memcg = NULL; + + cgroup_sk_clone(&newsk->sk_cgrp_data); + + rcu_read_lock(); + filter = rcu_dereference(sk->sk_filter); + if (filter != NULL) + /* though it's an empty new sock, the charging may fail + * if sysctl_optmem_max was changed between creation of + * original socket and cloning + */ + is_charged = sk_filter_charge(newsk, filter); + RCU_INIT_POINTER(newsk->sk_filter, filter); + rcu_read_unlock(); + + if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) { + /* We need to make sure that we don't uncharge the new + * socket if we couldn't charge it in the first place + * as otherwise we uncharge the parent's filter. + */ + if (!is_charged) + RCU_INIT_POINTER(newsk->sk_filter, NULL); + sk_free_unlock_clone(newsk); + newsk = NULL; + goto out; + } + RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL); + + newsk->sk_err = 0; + newsk->sk_err_soft = 0; + newsk->sk_priority = 0; + newsk->sk_incoming_cpu = raw_smp_processor_id(); + atomic64_set(&newsk->sk_cookie, 0); + if (likely(newsk->sk_net_refcnt)) + sock_inuse_add(sock_net(newsk), 1); + + /* + * Before updating sk_refcnt, we must commit prior changes to memory + * (Documentation/RCU/rculist_nulls.txt for details) + */ + smp_wmb(); + refcount_set(&newsk->sk_refcnt, 2); + + /* + * Increment the counter in the same struct proto as the master + * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that + * is the same as sk->sk_prot->socks, as this field was copied + * with memcpy). + * + * This _changes_ the previous behaviour, where + * tcp_create_openreq_child always was incrementing the + * equivalent to tcp_prot->socks (inet_sock_nr), so this have + * to be taken into account in all callers. -acme + */ + sk_refcnt_debug_inc(newsk); + sk_set_socket(newsk, NULL); + sk_tx_queue_clear(newsk); + newsk->sk_wq = NULL; + + if (newsk->sk_prot->sockets_allocated) + sk_sockets_allocated_inc(newsk); + + if (sock_needs_netstamp(sk) && + newsk->sk_flags & SK_FLAGS_TIMESTAMP) + net_enable_timestamp(); + } +out: + return newsk; +} +EXPORT_SYMBOL_GPL(sk_clone_lock); + +void sk_free_unlock_clone(struct sock *sk) +{ + /* It is still raw copy of parent, so invalidate + * destructor and make plain sk_free() */ + sk->sk_destruct = NULL; + bh_unlock_sock(sk); + sk_free(sk); +} +EXPORT_SYMBOL_GPL(sk_free_unlock_clone); + +void sk_setup_caps(struct sock *sk, struct dst_entry *dst) +{ + u32 max_segs = 1; + + sk_dst_set(sk, dst); + sk->sk_route_caps = dst->dev->features | sk->sk_route_forced_caps; + if (sk->sk_route_caps & NETIF_F_GSO) + sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; + sk->sk_route_caps &= ~sk->sk_route_nocaps; + if (sk_can_gso(sk)) { + if (dst->header_len && !xfrm_dst_offload_ok(dst)) { + sk->sk_route_caps &= ~NETIF_F_GSO_MASK; + } else { + sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; + sk->sk_gso_max_size = dst->dev->gso_max_size; + max_segs = max_t(u32, dst->dev->gso_max_segs, 1); + } + } + sk->sk_gso_max_segs = max_segs; +} +EXPORT_SYMBOL_GPL(sk_setup_caps); + +/* + * Simple resource managers for sockets. + */ + + +/* + * Write buffer destructor automatically called from kfree_skb. + */ +void sock_wfree(struct sk_buff *skb) +{ + struct sock *sk = skb->sk; + unsigned int len = skb->truesize; + + if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { + /* + * Keep a reference on sk_wmem_alloc, this will be released + * after sk_write_space() call + */ + WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc)); + sk->sk_write_space(sk); + len = 1; + } + /* + * if sk_wmem_alloc reaches 0, we must finish what sk_free() + * could not do because of in-flight packets + */ + if (refcount_sub_and_test(len, &sk->sk_wmem_alloc)) + __sk_free(sk); +} +EXPORT_SYMBOL(sock_wfree); + +/* This variant of sock_wfree() is used by TCP, + * since it sets SOCK_USE_WRITE_QUEUE. + */ +void __sock_wfree(struct sk_buff *skb) +{ + struct sock *sk = skb->sk; + + if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc)) + __sk_free(sk); +} + +void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) +{ + skb_orphan(skb); + skb->sk = sk; +#ifdef CONFIG_INET + if (unlikely(!sk_fullsock(sk))) { + skb->destructor = sock_edemux; + sock_hold(sk); + return; + } +#endif + skb->destructor = sock_wfree; + skb_set_hash_from_sk(skb, sk); + /* + * We used to take a refcount on sk, but following operation + * is enough to guarantee sk_free() wont free this sock until + * all in-flight packets are completed + */ + refcount_add(skb->truesize, &sk->sk_wmem_alloc); +} +EXPORT_SYMBOL(skb_set_owner_w); + +/* This helper is used by netem, as it can hold packets in its + * delay queue. We want to allow the owner socket to send more + * packets, as if they were already TX completed by a typical driver. + * But we also want to keep skb->sk set because some packet schedulers + * rely on it (sch_fq for example). + */ +void skb_orphan_partial(struct sk_buff *skb) +{ + if (skb_is_tcp_pure_ack(skb)) + return; + + if (skb->destructor == sock_wfree +#ifdef CONFIG_INET + || skb->destructor == tcp_wfree +#endif + ) { + struct sock *sk = skb->sk; + + if (refcount_inc_not_zero(&sk->sk_refcnt)) { + WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc)); + skb->destructor = sock_efree; + } + } else { + skb_orphan(skb); + } +} +EXPORT_SYMBOL(skb_orphan_partial); + +/* + * Read buffer destructor automatically called from kfree_skb. + */ +void sock_rfree(struct sk_buff *skb) +{ + struct sock *sk = skb->sk; + unsigned int len = skb->truesize; + + atomic_sub(len, &sk->sk_rmem_alloc); + sk_mem_uncharge(sk, len); +} +EXPORT_SYMBOL(sock_rfree); + +/* + * Buffer destructor for skbs that are not used directly in read or write + * path, e.g. for error handler skbs. Automatically called from kfree_skb. + */ +void sock_efree(struct sk_buff *skb) +{ + sock_put(skb->sk); +} +EXPORT_SYMBOL(sock_efree); + +kuid_t sock_i_uid(struct sock *sk) +{ + kuid_t uid; + + read_lock_bh(&sk->sk_callback_lock); + uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; + read_unlock_bh(&sk->sk_callback_lock); + return uid; +} +EXPORT_SYMBOL(sock_i_uid); + +unsigned long sock_i_ino(struct sock *sk) +{ + unsigned long ino; + + read_lock_bh(&sk->sk_callback_lock); + ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; + read_unlock_bh(&sk->sk_callback_lock); + return ino; +} +EXPORT_SYMBOL(sock_i_ino); + +/* + * Allocate a skb from the socket's send buffer. + */ +struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, + gfp_t priority) +{ + if (force || refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { + struct sk_buff *skb = alloc_skb(size, priority); + if (skb) { + skb_set_owner_w(skb, sk); + return skb; + } + } + return NULL; +} +EXPORT_SYMBOL(sock_wmalloc); + +static void sock_ofree(struct sk_buff *skb) +{ + struct sock *sk = skb->sk; + + atomic_sub(skb->truesize, &sk->sk_omem_alloc); +} + +struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, + gfp_t priority) +{ + struct sk_buff *skb; + + /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */ + if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) > + sysctl_optmem_max) + return NULL; + + skb = alloc_skb(size, priority); + if (!skb) + return NULL; + + atomic_add(skb->truesize, &sk->sk_omem_alloc); + skb->sk = sk; + skb->destructor = sock_ofree; + return skb; +} + +/* + * Allocate a memory block from the socket's option memory buffer. + */ +void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) +{ + if ((unsigned int)size <= sysctl_optmem_max && + atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { + void *mem; + /* First do the add, to avoid the race if kmalloc + * might sleep. + */ + atomic_add(size, &sk->sk_omem_alloc); + mem = kmalloc(size, priority); + if (mem) + return mem; + atomic_sub(size, &sk->sk_omem_alloc); + } + return NULL; +} +EXPORT_SYMBOL(sock_kmalloc); + +/* Free an option memory block. Note, we actually want the inline + * here as this allows gcc to detect the nullify and fold away the + * condition entirely. + */ +static inline void __sock_kfree_s(struct sock *sk, void *mem, int size, + const bool nullify) +{ + if (WARN_ON_ONCE(!mem)) + return; + if (nullify) + kzfree(mem); + else + kfree(mem); + atomic_sub(size, &sk->sk_omem_alloc); +} + +void sock_kfree_s(struct sock *sk, void *mem, int size) +{ + __sock_kfree_s(sk, mem, size, false); +} +EXPORT_SYMBOL(sock_kfree_s); + +void sock_kzfree_s(struct sock *sk, void *mem, int size) +{ + __sock_kfree_s(sk, mem, size, true); +} +EXPORT_SYMBOL(sock_kzfree_s); + +/* It is almost wait_for_tcp_memory minus release_sock/lock_sock. + I think, these locks should be removed for datagram sockets. + */ +static long sock_wait_for_wmem(struct sock *sk, long timeo) +{ + DEFINE_WAIT(wait); + + sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); + for (;;) { + if (!timeo) + break; + if (signal_pending(current)) + break; + set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); + prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); + if (refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) + break; + if (sk->sk_shutdown & SEND_SHUTDOWN) + break; + if (sk->sk_err) + break; + timeo = schedule_timeout(timeo); + } + finish_wait(sk_sleep(sk), &wait); + return timeo; +} + + +/* + * Generic send/receive buffer handlers + */ + +struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, + unsigned long data_len, int noblock, + int *errcode, int max_page_order) +{ + struct sk_buff *skb; + long timeo; + int err; + + timeo = sock_sndtimeo(sk, noblock); + for (;;) { + err = sock_error(sk); + if (err != 0) + goto failure; + + err = -EPIPE; + if (sk->sk_shutdown & SEND_SHUTDOWN) + goto failure; + + if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf) + break; + + sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk); + set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); + err = -EAGAIN; + if (!timeo) + goto failure; + if (signal_pending(current)) + goto interrupted; + timeo = sock_wait_for_wmem(sk, timeo); + } + skb = alloc_skb_with_frags(header_len, data_len, max_page_order, + errcode, sk->sk_allocation); + if (skb) + skb_set_owner_w(skb, sk); + return skb; + +interrupted: + err = sock_intr_errno(timeo); +failure: + *errcode = err; + return NULL; +} +EXPORT_SYMBOL(sock_alloc_send_pskb); + +struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, + int noblock, int *errcode) +{ + return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); +} +EXPORT_SYMBOL(sock_alloc_send_skb); + +int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, + struct sockcm_cookie *sockc) +{ + u32 tsflags; + + switch (cmsg->cmsg_type) { + case SO_MARK: + if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) + return -EPERM; + if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) + return -EINVAL; + sockc->mark = *(u32 *)CMSG_DATA(cmsg); + break; + case SO_TIMESTAMPING: + if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) + return -EINVAL; + + tsflags = *(u32 *)CMSG_DATA(cmsg); + if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK) + return -EINVAL; + + sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK; + sockc->tsflags |= tsflags; + break; + case SCM_TXTIME: + if (!sock_flag(sk, SOCK_TXTIME)) + return -EINVAL; + if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64))) + return -EINVAL; + sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg)); + break; + /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */ + case SCM_RIGHTS: + case SCM_CREDENTIALS: + break; + default: + return -EINVAL; + } + return 0; +} +EXPORT_SYMBOL(__sock_cmsg_send); + +int sock_cmsg_send(struct sock *sk, struct msghdr *msg, + struct sockcm_cookie *sockc) +{ + struct cmsghdr *cmsg; + int ret; + + for_each_cmsghdr(cmsg, msg) { + if (!CMSG_OK(msg, cmsg)) + return -EINVAL; + if (cmsg->cmsg_level != SOL_SOCKET) + continue; + ret = __sock_cmsg_send(sk, msg, cmsg, sockc); + if (ret) + return ret; + } + return 0; +} +EXPORT_SYMBOL(sock_cmsg_send); + +static void sk_enter_memory_pressure(struct sock *sk) +{ + if (!sk->sk_prot->enter_memory_pressure) + return; + + sk->sk_prot->enter_memory_pressure(sk); +} + +static void sk_leave_memory_pressure(struct sock *sk) +{ + if (sk->sk_prot->leave_memory_pressure) { + sk->sk_prot->leave_memory_pressure(sk); + } else { + unsigned long *memory_pressure = sk->sk_prot->memory_pressure; + + if (memory_pressure && READ_ONCE(*memory_pressure)) + WRITE_ONCE(*memory_pressure, 0); + } +} + +/** + * skb_page_frag_refill - check that a page_frag contains enough room + * @sz: minimum size of the fragment we want to get + * @pfrag: pointer to page_frag + * @gfp: priority for memory allocation + * + * Note: While this allocator tries to use high order pages, there is + * no guarantee that allocations succeed. Therefore, @sz MUST be + * less or equal than PAGE_SIZE. + */ +bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp) +{ + if (pfrag->page) { + if (page_ref_count(pfrag->page) == 1) { + pfrag->offset = 0; + return true; + } + if (pfrag->offset + sz <= pfrag->size) + return true; + put_page(pfrag->page); + } + + pfrag->offset = 0; + if (SKB_FRAG_PAGE_ORDER) { + /* Avoid direct reclaim but allow kswapd to wake */ + pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) | + __GFP_COMP | __GFP_NOWARN | + __GFP_NORETRY, + SKB_FRAG_PAGE_ORDER); + if (likely(pfrag->page)) { + pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER; + return true; + } + } + pfrag->page = alloc_page(gfp); + if (likely(pfrag->page)) { + pfrag->size = PAGE_SIZE; + return true; + } + return false; +} +EXPORT_SYMBOL(skb_page_frag_refill); + +bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) +{ + if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) + return true; + + sk_enter_memory_pressure(sk); + sk_stream_moderate_sndbuf(sk); + return false; +} +EXPORT_SYMBOL(sk_page_frag_refill); + +int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg, + int sg_start, int *sg_curr_index, unsigned int *sg_curr_size, + int first_coalesce) +{ + int sg_curr = *sg_curr_index, use = 0, rc = 0; + unsigned int size = *sg_curr_size; + struct page_frag *pfrag; + struct scatterlist *sge; + + len -= size; + pfrag = sk_page_frag(sk); + + while (len > 0) { + unsigned int orig_offset; + + if (!sk_page_frag_refill(sk, pfrag)) { + rc = -ENOMEM; + goto out; + } + + use = min_t(int, len, pfrag->size - pfrag->offset); + + if (!sk_wmem_schedule(sk, use)) { + rc = -ENOMEM; + goto out; + } + + sk_mem_charge(sk, use); + size += use; + orig_offset = pfrag->offset; + pfrag->offset += use; + + sge = sg + sg_curr - 1; + if (sg_curr > first_coalesce && sg_page(sge) == pfrag->page && + sge->offset + sge->length == orig_offset) { + sge->length += use; + } else { + sge = sg + sg_curr; + sg_unmark_end(sge); + sg_set_page(sge, pfrag->page, use, orig_offset); + get_page(pfrag->page); + sg_curr++; + + if (sg_curr == MAX_SKB_FRAGS) + sg_curr = 0; + + if (sg_curr == sg_start) { + rc = -ENOSPC; + break; + } + } + + len -= use; + } +out: + *sg_curr_size = size; + *sg_curr_index = sg_curr; + return rc; +} +EXPORT_SYMBOL(sk_alloc_sg); + +static void __lock_sock(struct sock *sk) + __releases(&sk->sk_lock.slock) + __acquires(&sk->sk_lock.slock) +{ + DEFINE_WAIT(wait); + + for (;;) { + prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, + TASK_UNINTERRUPTIBLE); + spin_unlock_bh(&sk->sk_lock.slock); + schedule(); + spin_lock_bh(&sk->sk_lock.slock); + if (!sock_owned_by_user(sk)) + break; + } + finish_wait(&sk->sk_lock.wq, &wait); +} + +void __release_sock(struct sock *sk) + __releases(&sk->sk_lock.slock) + __acquires(&sk->sk_lock.slock) +{ + struct sk_buff *skb, *next; + + while ((skb = sk->sk_backlog.head) != NULL) { + sk->sk_backlog.head = sk->sk_backlog.tail = NULL; + + spin_unlock_bh(&sk->sk_lock.slock); + + do { + next = skb->next; + prefetch(next); + WARN_ON_ONCE(skb_dst_is_noref(skb)); + skb->next = NULL; + sk_backlog_rcv(sk, skb); + + cond_resched(); + + skb = next; + } while (skb != NULL); + + spin_lock_bh(&sk->sk_lock.slock); + } + + /* + * Doing the zeroing here guarantee we can not loop forever + * while a wild producer attempts to flood us. + */ + sk->sk_backlog.len = 0; +} + +void __sk_flush_backlog(struct sock *sk) +{ + spin_lock_bh(&sk->sk_lock.slock); + __release_sock(sk); + spin_unlock_bh(&sk->sk_lock.slock); +} + +/** + * sk_wait_data - wait for data to arrive at sk_receive_queue + * @sk: sock to wait on + * @timeo: for how long + * @skb: last skb seen on sk_receive_queue + * + * Now socket state including sk->sk_err is changed only under lock, + * hence we may omit checks after joining wait queue. + * We check receive queue before schedule() only as optimization; + * it is very likely that release_sock() added new data. + */ +int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb) +{ + DEFINE_WAIT_FUNC(wait, woken_wake_function); + int rc; + + add_wait_queue(sk_sleep(sk), &wait); + sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); + rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait); + sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); + remove_wait_queue(sk_sleep(sk), &wait); + return rc; +} +EXPORT_SYMBOL(sk_wait_data); + +/** + * __sk_mem_raise_allocated - increase memory_allocated + * @sk: socket + * @size: memory size to allocate + * @amt: pages to allocate + * @kind: allocation type + * + * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc + */ +int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind) +{ + struct proto *prot = sk->sk_prot; + long allocated = sk_memory_allocated_add(sk, amt); + bool charged = true; + + if (mem_cgroup_sockets_enabled && sk->sk_memcg && + !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt))) + goto suppress_allocation; + + /* Under limit. */ + if (allocated <= sk_prot_mem_limits(sk, 0)) { + sk_leave_memory_pressure(sk); + return 1; + } + + /* Under pressure. */ + if (allocated > sk_prot_mem_limits(sk, 1)) + sk_enter_memory_pressure(sk); + + /* Over hard limit. */ + if (allocated > sk_prot_mem_limits(sk, 2)) + goto suppress_allocation; + + /* guarantee minimum buffer size under pressure */ + if (kind == SK_MEM_RECV) { + if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot)) + return 1; + + } else { /* SK_MEM_SEND */ + int wmem0 = sk_get_wmem0(sk, prot); + + if (sk->sk_type == SOCK_STREAM) { + if (sk->sk_wmem_queued < wmem0) + return 1; + } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) { + return 1; + } + } + + if (sk_has_memory_pressure(sk)) { + u64 alloc; + + if (!sk_under_memory_pressure(sk)) + return 1; + alloc = sk_sockets_allocated_read_positive(sk); + if (sk_prot_mem_limits(sk, 2) > alloc * + sk_mem_pages(sk->sk_wmem_queued + + atomic_read(&sk->sk_rmem_alloc) + + sk->sk_forward_alloc)) + return 1; + } + +suppress_allocation: + + if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { + sk_stream_moderate_sndbuf(sk); + + /* Fail only if socket is _under_ its sndbuf. + * In this case we cannot block, so that we have to fail. + */ + if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) + return 1; + } + + if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged)) + trace_sock_exceed_buf_limit(sk, prot, allocated, kind); + + sk_memory_allocated_sub(sk, amt); + + if (mem_cgroup_sockets_enabled && sk->sk_memcg) + mem_cgroup_uncharge_skmem(sk->sk_memcg, amt); + + return 0; +} +EXPORT_SYMBOL(__sk_mem_raise_allocated); + +/** + * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated + * @sk: socket + * @size: memory size to allocate + * @kind: allocation type + * + * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means + * rmem allocation. This function assumes that protocols which have + * memory_pressure use sk_wmem_queued as write buffer accounting. + */ +int __sk_mem_schedule(struct sock *sk, int size, int kind) +{ + int ret, amt = sk_mem_pages(size); + + sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT; + ret = __sk_mem_raise_allocated(sk, size, amt, kind); + if (!ret) + sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT; + return ret; +} +EXPORT_SYMBOL(__sk_mem_schedule); + +/** + * __sk_mem_reduce_allocated - reclaim memory_allocated + * @sk: socket + * @amount: number of quanta + * + * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc + */ +void __sk_mem_reduce_allocated(struct sock *sk, int amount) +{ + sk_memory_allocated_sub(sk, amount); + + if (mem_cgroup_sockets_enabled && sk->sk_memcg) + mem_cgroup_uncharge_skmem(sk->sk_memcg, amount); + + if (sk_under_memory_pressure(sk) && + (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) + sk_leave_memory_pressure(sk); +} +EXPORT_SYMBOL(__sk_mem_reduce_allocated); + +/** + * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated + * @sk: socket + * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple) + */ +void __sk_mem_reclaim(struct sock *sk, int amount) +{ + amount >>= SK_MEM_QUANTUM_SHIFT; + sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT; + __sk_mem_reduce_allocated(sk, amount); +} +EXPORT_SYMBOL(__sk_mem_reclaim); + +int sk_set_peek_off(struct sock *sk, int val) +{ + sk->sk_peek_off = val; + return 0; +} +EXPORT_SYMBOL_GPL(sk_set_peek_off); + +/* + * Set of default routines for initialising struct proto_ops when + * the protocol does not support a particular function. In certain + * cases where it makes no sense for a protocol to have a "do nothing" + * function, some default processing is provided. + */ + +int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(sock_no_bind); + +int sock_no_connect(struct socket *sock, struct sockaddr *saddr, + int len, int flags) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(sock_no_connect); + +int sock_no_socketpair(struct socket *sock1, struct socket *sock2) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(sock_no_socketpair); + +int sock_no_accept(struct socket *sock, struct socket *newsock, int flags, + bool kern) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(sock_no_accept); + +int sock_no_getname(struct socket *sock, struct sockaddr *saddr, + int peer) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(sock_no_getname); + +int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(sock_no_ioctl); + +int sock_no_listen(struct socket *sock, int backlog) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(sock_no_listen); + +int sock_no_shutdown(struct socket *sock, int how) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(sock_no_shutdown); + +int sock_no_setsockopt(struct socket *sock, int level, int optname, + char __user *optval, unsigned int optlen) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(sock_no_setsockopt); + +int sock_no_getsockopt(struct socket *sock, int level, int optname, + char __user *optval, int __user *optlen) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(sock_no_getsockopt); + +int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(sock_no_sendmsg); + +int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(sock_no_sendmsg_locked); + +int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len, + int flags) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(sock_no_recvmsg); + +int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) +{ + /* Mirror missing mmap method error code */ + return -ENODEV; +} +EXPORT_SYMBOL(sock_no_mmap); + +/* + * When a file is received (via SCM_RIGHTS, etc), we must bump the + * various sock-based usage counts. + */ +void __receive_sock(struct file *file) +{ + struct socket *sock; + int error; + + /* + * The resulting value of "error" is ignored here since we only + * need to take action when the file is a socket and testing + * "sock" for NULL is sufficient. + */ + sock = sock_from_file(file, &error); + if (sock) { + sock_update_netprioidx(&sock->sk->sk_cgrp_data); + sock_update_classid(&sock->sk->sk_cgrp_data); + } +} + +ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) +{ + ssize_t res; + struct msghdr msg = {.msg_flags = flags}; + struct kvec iov; + char *kaddr = kmap(page); + iov.iov_base = kaddr + offset; + iov.iov_len = size; + res = kernel_sendmsg(sock, &msg, &iov, 1, size); + kunmap(page); + return res; +} +EXPORT_SYMBOL(sock_no_sendpage); + +ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page, + int offset, size_t size, int flags) +{ + ssize_t res; + struct msghdr msg = {.msg_flags = flags}; + struct kvec iov; + char *kaddr = kmap(page); + + iov.iov_base = kaddr + offset; + iov.iov_len = size; + res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size); + kunmap(page); + return res; +} +EXPORT_SYMBOL(sock_no_sendpage_locked); + +/* + * Default Socket Callbacks + */ + +static void sock_def_wakeup(struct sock *sk) +{ + struct socket_wq *wq; + + rcu_read_lock(); + wq = rcu_dereference(sk->sk_wq); + if (skwq_has_sleeper(wq)) + wake_up_interruptible_all(&wq->wait); + rcu_read_unlock(); +} + +static void sock_def_error_report(struct sock *sk) +{ + struct socket_wq *wq; + + rcu_read_lock(); + wq = rcu_dereference(sk->sk_wq); + if (skwq_has_sleeper(wq)) + wake_up_interruptible_poll(&wq->wait, EPOLLERR); + sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); + rcu_read_unlock(); +} + +static void sock_def_readable(struct sock *sk) +{ + struct socket_wq *wq; + + rcu_read_lock(); + wq = rcu_dereference(sk->sk_wq); + if (skwq_has_sleeper(wq)) + wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI | + EPOLLRDNORM | EPOLLRDBAND); + sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); + rcu_read_unlock(); +} + +static void sock_def_write_space(struct sock *sk) +{ + struct socket_wq *wq; + + rcu_read_lock(); + + /* Do not wake up a writer until he can make "significant" + * progress. --DaveM + */ + if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { + wq = rcu_dereference(sk->sk_wq); + if (skwq_has_sleeper(wq)) + wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT | + EPOLLWRNORM | EPOLLWRBAND); + + /* Should agree with poll, otherwise some programs break */ + if (sock_writeable(sk)) + sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); + } + + rcu_read_unlock(); +} + +static void sock_def_destruct(struct sock *sk) +{ +} + +void sk_send_sigurg(struct sock *sk) +{ + if (sk->sk_socket && sk->sk_socket->file) + if (send_sigurg(&sk->sk_socket->file->f_owner)) + sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); +} +EXPORT_SYMBOL(sk_send_sigurg); + +void sk_reset_timer(struct sock *sk, struct timer_list* timer, + unsigned long expires) +{ + if (!mod_timer(timer, expires)) + sock_hold(sk); +} +EXPORT_SYMBOL(sk_reset_timer); + +void sk_stop_timer(struct sock *sk, struct timer_list* timer) +{ + if (del_timer(timer)) + __sock_put(sk); +} +EXPORT_SYMBOL(sk_stop_timer); + +void sock_init_data(struct socket *sock, struct sock *sk) +{ + sk_init_common(sk); + sk->sk_send_head = NULL; + + timer_setup(&sk->sk_timer, NULL, 0); + + sk->sk_allocation = GFP_KERNEL; + sk->sk_rcvbuf = sysctl_rmem_default; + sk->sk_sndbuf = sysctl_wmem_default; + sk->sk_state = TCP_CLOSE; + sk_set_socket(sk, sock); + + sock_set_flag(sk, SOCK_ZAPPED); + + if (sock) { + sk->sk_type = sock->type; + sk->sk_wq = sock->wq; + sock->sk = sk; + sk->sk_uid = SOCK_INODE(sock)->i_uid; + } else { + sk->sk_wq = NULL; + sk->sk_uid = make_kuid(sock_net(sk)->user_ns, 0); + } + + rwlock_init(&sk->sk_callback_lock); + if (sk->sk_kern_sock) + lockdep_set_class_and_name( + &sk->sk_callback_lock, + af_kern_callback_keys + sk->sk_family, + af_family_kern_clock_key_strings[sk->sk_family]); + else + lockdep_set_class_and_name( + &sk->sk_callback_lock, + af_callback_keys + sk->sk_family, + af_family_clock_key_strings[sk->sk_family]); + + sk->sk_state_change = sock_def_wakeup; + sk->sk_data_ready = sock_def_readable; + sk->sk_write_space = sock_def_write_space; + sk->sk_error_report = sock_def_error_report; + sk->sk_destruct = sock_def_destruct; + + sk->sk_frag.page = NULL; + sk->sk_frag.offset = 0; + sk->sk_peek_off = -1; + + sk->sk_peer_pid = NULL; + sk->sk_peer_cred = NULL; + spin_lock_init(&sk->sk_peer_lock); + + sk->sk_write_pending = 0; + sk->sk_rcvlowat = 1; + sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; + sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; + + sk->sk_stamp = SK_DEFAULT_STAMP; +#if BITS_PER_LONG==32 + seqlock_init(&sk->sk_stamp_seq); +#endif + atomic_set(&sk->sk_zckey, 0); + +#ifdef CONFIG_NET_RX_BUSY_POLL + sk->sk_napi_id = 0; + sk->sk_ll_usec = sysctl_net_busy_read; +#endif + + sk->sk_max_pacing_rate = ~0U; + sk->sk_pacing_rate = ~0U; + sk->sk_pacing_shift = 10; + sk->sk_incoming_cpu = -1; + + sk_rx_queue_clear(sk); + /* + * Before updating sk_refcnt, we must commit prior changes to memory + * (Documentation/RCU/rculist_nulls.txt for details) + */ + smp_wmb(); + refcount_set(&sk->sk_refcnt, 1); + atomic_set(&sk->sk_drops, 0); +} +EXPORT_SYMBOL(sock_init_data); + +void lock_sock_nested(struct sock *sk, int subclass) +{ + might_sleep(); + spin_lock_bh(&sk->sk_lock.slock); + if (sk->sk_lock.owned) + __lock_sock(sk); + sk->sk_lock.owned = 1; + spin_unlock(&sk->sk_lock.slock); + /* + * The sk_lock has mutex_lock() semantics here: + */ + mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); + local_bh_enable(); +} +EXPORT_SYMBOL(lock_sock_nested); + +void release_sock(struct sock *sk) +{ + spin_lock_bh(&sk->sk_lock.slock); + if (sk->sk_backlog.tail) + __release_sock(sk); + + /* Warning : release_cb() might need to release sk ownership, + * ie call sock_release_ownership(sk) before us. + */ + if (sk->sk_prot->release_cb) + sk->sk_prot->release_cb(sk); + + sock_release_ownership(sk); + if (waitqueue_active(&sk->sk_lock.wq)) + wake_up(&sk->sk_lock.wq); + spin_unlock_bh(&sk->sk_lock.slock); +} +EXPORT_SYMBOL(release_sock); + +/** + * lock_sock_fast - fast version of lock_sock + * @sk: socket + * + * This version should be used for very small section, where process wont block + * return false if fast path is taken: + * + * sk_lock.slock locked, owned = 0, BH disabled + * + * return true if slow path is taken: + * + * sk_lock.slock unlocked, owned = 1, BH enabled + */ +bool lock_sock_fast(struct sock *sk) +{ + might_sleep(); + spin_lock_bh(&sk->sk_lock.slock); + + if (!sk->sk_lock.owned) + /* + * Note : We must disable BH + */ + return false; + + __lock_sock(sk); + sk->sk_lock.owned = 1; + spin_unlock(&sk->sk_lock.slock); + /* + * The sk_lock has mutex_lock() semantics here: + */ + mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); + local_bh_enable(); + return true; +} +EXPORT_SYMBOL(lock_sock_fast); + +int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) +{ + struct timeval tv; + + sock_enable_timestamp(sk, SOCK_TIMESTAMP); + tv = ktime_to_timeval(sock_read_timestamp(sk)); + if (tv.tv_sec == -1) + return -ENOENT; + if (tv.tv_sec == 0) { + ktime_t kt = ktime_get_real(); + sock_write_timestamp(sk, kt); + tv = ktime_to_timeval(kt); + } + return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; +} +EXPORT_SYMBOL(sock_get_timestamp); + +int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) +{ + struct timespec ts; + + sock_enable_timestamp(sk, SOCK_TIMESTAMP); + ts = ktime_to_timespec(sock_read_timestamp(sk)); + if (ts.tv_sec == -1) + return -ENOENT; + if (ts.tv_sec == 0) { + ktime_t kt = ktime_get_real(); + sock_write_timestamp(sk, kt); + ts = ktime_to_timespec(sk->sk_stamp); + } + return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; +} +EXPORT_SYMBOL(sock_get_timestampns); + +void sock_enable_timestamp(struct sock *sk, int flag) +{ + if (!sock_flag(sk, flag)) { + unsigned long previous_flags = sk->sk_flags; + + sock_set_flag(sk, flag); + /* + * we just set one of the two flags which require net + * time stamping, but time stamping might have been on + * already because of the other one + */ + if (sock_needs_netstamp(sk) && + !(previous_flags & SK_FLAGS_TIMESTAMP)) + net_enable_timestamp(); + } +} + +int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, + int level, int type) +{ + struct sock_exterr_skb *serr; + struct sk_buff *skb; + int copied, err; + + err = -EAGAIN; + skb = sock_dequeue_err_skb(sk); + if (skb == NULL) + goto out; + + copied = skb->len; + if (copied > len) { + msg->msg_flags |= MSG_TRUNC; + copied = len; + } + err = skb_copy_datagram_msg(skb, 0, msg, copied); + if (err) + goto out_free_skb; + + sock_recv_timestamp(msg, sk, skb); + + serr = SKB_EXT_ERR(skb); + put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); + + msg->msg_flags |= MSG_ERRQUEUE; + err = copied; + +out_free_skb: + kfree_skb(skb); +out: + return err; +} +EXPORT_SYMBOL(sock_recv_errqueue); + +/* + * Get a socket option on an socket. + * + * FIX: POSIX 1003.1g is very ambiguous here. It states that + * asynchronous errors should be reported by getsockopt. We assume + * this means if you specify SO_ERROR (otherwise whats the point of it). + */ +int sock_common_getsockopt(struct socket *sock, int level, int optname, + char __user *optval, int __user *optlen) +{ + struct sock *sk = sock->sk; + + return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); +} +EXPORT_SYMBOL(sock_common_getsockopt); + +#ifdef CONFIG_COMPAT +int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, + char __user *optval, int __user *optlen) +{ + struct sock *sk = sock->sk; + + if (sk->sk_prot->compat_getsockopt != NULL) + return sk->sk_prot->compat_getsockopt(sk, level, optname, + optval, optlen); + return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); +} +EXPORT_SYMBOL(compat_sock_common_getsockopt); +#endif + +int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, + int flags) +{ + struct sock *sk = sock->sk; + int addr_len = 0; + int err; + + err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, + flags & ~MSG_DONTWAIT, &addr_len); + if (err >= 0) + msg->msg_namelen = addr_len; + return err; +} +EXPORT_SYMBOL(sock_common_recvmsg); + +/* + * Set socket options on an inet socket. + */ +int sock_common_setsockopt(struct socket *sock, int level, int optname, + char __user *optval, unsigned int optlen) +{ + struct sock *sk = sock->sk; + + return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); +} +EXPORT_SYMBOL(sock_common_setsockopt); + +#ifdef CONFIG_COMPAT +int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, + char __user *optval, unsigned int optlen) +{ + struct sock *sk = sock->sk; + + if (sk->sk_prot->compat_setsockopt != NULL) + return sk->sk_prot->compat_setsockopt(sk, level, optname, + optval, optlen); + return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); +} +EXPORT_SYMBOL(compat_sock_common_setsockopt); +#endif + +void sk_common_release(struct sock *sk) +{ + if (sk->sk_prot->destroy) + sk->sk_prot->destroy(sk); + + /* + * Observation: when sock_common_release is called, processes have + * no access to socket. But net still has. + * Step one, detach it from networking: + * + * A. Remove from hash tables. + */ + + sk->sk_prot->unhash(sk); + + /* + * In this point socket cannot receive new packets, but it is possible + * that some packets are in flight because some CPU runs receiver and + * did hash table lookup before we unhashed socket. They will achieve + * receive queue and will be purged by socket destructor. + * + * Also we still have packets pending on receive queue and probably, + * our own packets waiting in device queues. sock_destroy will drain + * receive queue, but transmitted packets will delay socket destruction + * until the last reference will be released. + */ + + sock_orphan(sk); + + xfrm_sk_free_policy(sk); + + sk_refcnt_debug_release(sk); + + sock_put(sk); +} +EXPORT_SYMBOL(sk_common_release); + +void sk_get_meminfo(const struct sock *sk, u32 *mem) +{ + memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS); + + mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk); + mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf; + mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk); + mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf; + mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc; + mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued; + mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc); + mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len; + mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops); +} + +#ifdef CONFIG_PROC_FS +#define PROTO_INUSE_NR 64 /* should be enough for the first time */ +struct prot_inuse { + int val[PROTO_INUSE_NR]; +}; + +static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); + +void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) +{ + __this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val); +} +EXPORT_SYMBOL_GPL(sock_prot_inuse_add); + +int sock_prot_inuse_get(struct net *net, struct proto *prot) +{ + int cpu, idx = prot->inuse_idx; + int res = 0; + + for_each_possible_cpu(cpu) + res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx]; + + return res >= 0 ? res : 0; +} +EXPORT_SYMBOL_GPL(sock_prot_inuse_get); + +static void sock_inuse_add(struct net *net, int val) +{ + this_cpu_add(*net->core.sock_inuse, val); +} + +int sock_inuse_get(struct net *net) +{ + int cpu, res = 0; + + for_each_possible_cpu(cpu) + res += *per_cpu_ptr(net->core.sock_inuse, cpu); + + return res; +} + +EXPORT_SYMBOL_GPL(sock_inuse_get); + +static int __net_init sock_inuse_init_net(struct net *net) +{ + net->core.prot_inuse = alloc_percpu(struct prot_inuse); + if (net->core.prot_inuse == NULL) + return -ENOMEM; + + net->core.sock_inuse = alloc_percpu(int); + if (net->core.sock_inuse == NULL) + goto out; + + return 0; + +out: + free_percpu(net->core.prot_inuse); + return -ENOMEM; +} + +static void __net_exit sock_inuse_exit_net(struct net *net) +{ + free_percpu(net->core.prot_inuse); + free_percpu(net->core.sock_inuse); +} + +static struct pernet_operations net_inuse_ops = { + .init = sock_inuse_init_net, + .exit = sock_inuse_exit_net, +}; + +static __init int net_inuse_init(void) +{ + if (register_pernet_subsys(&net_inuse_ops)) + panic("Cannot initialize net inuse counters"); + + return 0; +} + +core_initcall(net_inuse_init); + +static void assign_proto_idx(struct proto *prot) +{ + prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); + + if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { + pr_err("PROTO_INUSE_NR exhausted\n"); + return; + } + + set_bit(prot->inuse_idx, proto_inuse_idx); +} + +static void release_proto_idx(struct proto *prot) +{ + if (prot->inuse_idx != PROTO_INUSE_NR - 1) + clear_bit(prot->inuse_idx, proto_inuse_idx); +} +#else +static inline void assign_proto_idx(struct proto *prot) +{ +} + +static inline void release_proto_idx(struct proto *prot) +{ +} + +static void sock_inuse_add(struct net *net, int val) +{ +} +#endif + +static void req_prot_cleanup(struct request_sock_ops *rsk_prot) +{ + if (!rsk_prot) + return; + kfree(rsk_prot->slab_name); + rsk_prot->slab_name = NULL; + kmem_cache_destroy(rsk_prot->slab); + rsk_prot->slab = NULL; +} + +static int req_prot_init(const struct proto *prot) +{ + struct request_sock_ops *rsk_prot = prot->rsk_prot; + + if (!rsk_prot) + return 0; + + rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", + prot->name); + if (!rsk_prot->slab_name) + return -ENOMEM; + + rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name, + rsk_prot->obj_size, 0, + SLAB_ACCOUNT | prot->slab_flags, + NULL); + + if (!rsk_prot->slab) { + pr_crit("%s: Can't create request sock SLAB cache!\n", + prot->name); + return -ENOMEM; + } + return 0; +} + +int proto_register(struct proto *prot, int alloc_slab) +{ + if (alloc_slab) { + prot->slab = kmem_cache_create_usercopy(prot->name, + prot->obj_size, 0, + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT | + prot->slab_flags, + prot->useroffset, prot->usersize, + NULL); + + if (prot->slab == NULL) { + pr_crit("%s: Can't create sock SLAB cache!\n", + prot->name); + goto out; + } + + if (req_prot_init(prot)) + goto out_free_request_sock_slab; + + if (prot->twsk_prot != NULL) { + prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); + + if (prot->twsk_prot->twsk_slab_name == NULL) + goto out_free_request_sock_slab; + + prot->twsk_prot->twsk_slab = + kmem_cache_create(prot->twsk_prot->twsk_slab_name, + prot->twsk_prot->twsk_obj_size, + 0, + SLAB_ACCOUNT | + prot->slab_flags, + NULL); + if (prot->twsk_prot->twsk_slab == NULL) + goto out_free_timewait_sock_slab_name; + } + } + + mutex_lock(&proto_list_mutex); + list_add(&prot->node, &proto_list); + assign_proto_idx(prot); + mutex_unlock(&proto_list_mutex); + return 0; + +out_free_timewait_sock_slab_name: + kfree(prot->twsk_prot->twsk_slab_name); +out_free_request_sock_slab: + req_prot_cleanup(prot->rsk_prot); + + kmem_cache_destroy(prot->slab); + prot->slab = NULL; +out: + return -ENOBUFS; +} +EXPORT_SYMBOL(proto_register); + +void proto_unregister(struct proto *prot) +{ + mutex_lock(&proto_list_mutex); + release_proto_idx(prot); + list_del(&prot->node); + mutex_unlock(&proto_list_mutex); + + kmem_cache_destroy(prot->slab); + prot->slab = NULL; + + req_prot_cleanup(prot->rsk_prot); + + if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { + kmem_cache_destroy(prot->twsk_prot->twsk_slab); + kfree(prot->twsk_prot->twsk_slab_name); + prot->twsk_prot->twsk_slab = NULL; + } +} +EXPORT_SYMBOL(proto_unregister); + +int sock_load_diag_module(int family, int protocol) +{ + if (!protocol) { + if (!sock_is_registered(family)) + return -ENOENT; + + return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK, + NETLINK_SOCK_DIAG, family); + } + +#ifdef CONFIG_INET + if (family == AF_INET && + protocol != IPPROTO_RAW && + !rcu_access_pointer(inet_protos[protocol])) + return -ENOENT; +#endif + + return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK, + NETLINK_SOCK_DIAG, family, protocol); +} +EXPORT_SYMBOL(sock_load_diag_module); + +#ifdef CONFIG_PROC_FS +static void *proto_seq_start(struct seq_file *seq, loff_t *pos) + __acquires(proto_list_mutex) +{ + mutex_lock(&proto_list_mutex); + return seq_list_start_head(&proto_list, *pos); +} + +static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) +{ + return seq_list_next(v, &proto_list, pos); +} + +static void proto_seq_stop(struct seq_file *seq, void *v) + __releases(proto_list_mutex) +{ + mutex_unlock(&proto_list_mutex); +} + +static char proto_method_implemented(const void *method) +{ + return method == NULL ? 'n' : 'y'; +} +static long sock_prot_memory_allocated(struct proto *proto) +{ + return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; +} + +static char *sock_prot_memory_pressure(struct proto *proto) +{ + return proto->memory_pressure != NULL ? + proto_memory_pressure(proto) ? "yes" : "no" : "NI"; +} + +static void proto_seq_printf(struct seq_file *seq, struct proto *proto) +{ + + seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " + "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", + proto->name, + proto->obj_size, + sock_prot_inuse_get(seq_file_net(seq), proto), + sock_prot_memory_allocated(proto), + sock_prot_memory_pressure(proto), + proto->max_header, + proto->slab == NULL ? "no" : "yes", + module_name(proto->owner), + proto_method_implemented(proto->close), + proto_method_implemented(proto->connect), + proto_method_implemented(proto->disconnect), + proto_method_implemented(proto->accept), + proto_method_implemented(proto->ioctl), + proto_method_implemented(proto->init), + proto_method_implemented(proto->destroy), + proto_method_implemented(proto->shutdown), + proto_method_implemented(proto->setsockopt), + proto_method_implemented(proto->getsockopt), + proto_method_implemented(proto->sendmsg), + proto_method_implemented(proto->recvmsg), + proto_method_implemented(proto->sendpage), + proto_method_implemented(proto->bind), + proto_method_implemented(proto->backlog_rcv), + proto_method_implemented(proto->hash), + proto_method_implemented(proto->unhash), + proto_method_implemented(proto->get_port), + proto_method_implemented(proto->enter_memory_pressure)); +} + +static int proto_seq_show(struct seq_file *seq, void *v) +{ + if (v == &proto_list) + seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", + "protocol", + "size", + "sockets", + "memory", + "press", + "maxhdr", + "slab", + "module", + "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); + else + proto_seq_printf(seq, list_entry(v, struct proto, node)); + return 0; +} + +static const struct seq_operations proto_seq_ops = { + .start = proto_seq_start, + .next = proto_seq_next, + .stop = proto_seq_stop, + .show = proto_seq_show, +}; + +static __net_init int proto_init_net(struct net *net) +{ + if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops, + sizeof(struct seq_net_private))) + return -ENOMEM; + + return 0; +} + +static __net_exit void proto_exit_net(struct net *net) +{ + remove_proc_entry("protocols", net->proc_net); +} + + +static __net_initdata struct pernet_operations proto_net_ops = { + .init = proto_init_net, + .exit = proto_exit_net, +}; + +static int __init proto_init(void) +{ + return register_pernet_subsys(&proto_net_ops); +} + +subsys_initcall(proto_init); + +#endif /* PROC_FS */ + +#ifdef CONFIG_NET_RX_BUSY_POLL +bool sk_busy_loop_end(void *p, unsigned long start_time) +{ + struct sock *sk = p; + + return !skb_queue_empty_lockless(&sk->sk_receive_queue) || + sk_busy_loop_timeout(sk, start_time); +} +EXPORT_SYMBOL(sk_busy_loop_end); +#endif /* CONFIG_NET_RX_BUSY_POLL */ |