sock.c 66.8 KB
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/*
 * 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.
 *
 *
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 * Authors:	Ross Biro
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 *		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
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 *					code. The ACK stuff can wait and needs major
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 *					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.
 */

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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

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#include <linux/capability.h>
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#include <linux/errno.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/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>
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#include <linux/highmem.h>
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#include <linux/user_namespace.h>
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#include <linux/static_key.h>
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#include <linux/memcontrol.h>
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#include <linux/prefetch.h>
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#include <asm/uaccess.h>

#include <linux/netdevice.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
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#include <net/net_namespace.h>
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#include <net/request_sock.h>
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#include <net/sock.h>
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#include <linux/net_tstamp.h>
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#include <net/xfrm.h>
#include <linux/ipsec.h>
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#include <net/cls_cgroup.h>
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#include <net/netprio_cgroup.h>
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#include <linux/filter.h>

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#include <trace/events/sock.h>

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#ifdef CONFIG_INET
#include <net/tcp.h>
#endif

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static DEFINE_MUTEX(proto_list_mutex);
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static LIST_HEAD(proto_list);

#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
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int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
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{
	struct proto *proto;
	int ret = 0;

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	mutex_lock(&proto_list_mutex);
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	list_for_each_entry(proto, &proto_list, node) {
		if (proto->init_cgroup) {
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			ret = proto->init_cgroup(memcg, ss);
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			if (ret)
				goto out;
		}
	}

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	mutex_unlock(&proto_list_mutex);
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	return ret;
out:
	list_for_each_entry_continue_reverse(proto, &proto_list, node)
		if (proto->destroy_cgroup)
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			proto->destroy_cgroup(memcg);
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	mutex_unlock(&proto_list_mutex);
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	return ret;
}

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void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
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{
	struct proto *proto;

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	mutex_lock(&proto_list_mutex);
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	list_for_each_entry_reverse(proto, &proto_list, node)
		if (proto->destroy_cgroup)
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			proto->destroy_cgroup(memcg);
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	mutex_unlock(&proto_list_mutex);
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}
#endif

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/*
 * Each address family might have different locking rules, so we have
 * one slock key per address family:
 */
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static struct lock_class_key af_family_keys[AF_MAX];
static struct lock_class_key af_family_slock_keys[AF_MAX];

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struct static_key memcg_socket_limit_enabled;
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EXPORT_SYMBOL(memcg_socket_limit_enabled);

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/*
 * Make lock validator output more readable. (we pre-construct these
 * strings build-time, so that runtime initialization of socket
 * locks is fast):
 */
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static const char *const af_family_key_strings[AF_MAX+1] = {
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  "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX"     , "sk_lock-AF_INET"     ,
  "sk_lock-AF_AX25"  , "sk_lock-AF_IPX"      , "sk_lock-AF_APPLETALK",
  "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE"   , "sk_lock-AF_ATMPVC"   ,
  "sk_lock-AF_X25"   , "sk_lock-AF_INET6"    , "sk_lock-AF_ROSE"     ,
  "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI"  , "sk_lock-AF_SECURITY" ,
  "sk_lock-AF_KEY"   , "sk_lock-AF_NETLINK"  , "sk_lock-AF_PACKET"   ,
  "sk_lock-AF_ASH"   , "sk_lock-AF_ECONET"   , "sk_lock-AF_ATMSVC"   ,
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  "sk_lock-AF_RDS"   , "sk_lock-AF_SNA"      , "sk_lock-AF_IRDA"     ,
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  "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE"  , "sk_lock-AF_LLC"      ,
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  "sk_lock-27"       , "sk_lock-28"          , "sk_lock-AF_CAN"      ,
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  "sk_lock-AF_TIPC"  , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV"        ,
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  "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN"     , "sk_lock-AF_PHONET"   ,
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  "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG"      ,
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  "sk_lock-AF_NFC"   , "sk_lock-AF_MAX"
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};
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static const char *const af_family_slock_key_strings[AF_MAX+1] = {
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  "slock-AF_UNSPEC", "slock-AF_UNIX"     , "slock-AF_INET"     ,
  "slock-AF_AX25"  , "slock-AF_IPX"      , "slock-AF_APPLETALK",
  "slock-AF_NETROM", "slock-AF_BRIDGE"   , "slock-AF_ATMPVC"   ,
  "slock-AF_X25"   , "slock-AF_INET6"    , "slock-AF_ROSE"     ,
  "slock-AF_DECnet", "slock-AF_NETBEUI"  , "slock-AF_SECURITY" ,
  "slock-AF_KEY"   , "slock-AF_NETLINK"  , "slock-AF_PACKET"   ,
  "slock-AF_ASH"   , "slock-AF_ECONET"   , "slock-AF_ATMSVC"   ,
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  "slock-AF_RDS"   , "slock-AF_SNA"      , "slock-AF_IRDA"     ,
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  "slock-AF_PPPOX" , "slock-AF_WANPIPE"  , "slock-AF_LLC"      ,
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  "slock-27"       , "slock-28"          , "slock-AF_CAN"      ,
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  "slock-AF_TIPC"  , "slock-AF_BLUETOOTH", "slock-AF_IUCV"     ,
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  "slock-AF_RXRPC" , "slock-AF_ISDN"     , "slock-AF_PHONET"   ,
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  "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG"      ,
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  "slock-AF_NFC"   , "slock-AF_MAX"
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};
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static const char *const af_family_clock_key_strings[AF_MAX+1] = {
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  "clock-AF_UNSPEC", "clock-AF_UNIX"     , "clock-AF_INET"     ,
  "clock-AF_AX25"  , "clock-AF_IPX"      , "clock-AF_APPLETALK",
  "clock-AF_NETROM", "clock-AF_BRIDGE"   , "clock-AF_ATMPVC"   ,
  "clock-AF_X25"   , "clock-AF_INET6"    , "clock-AF_ROSE"     ,
  "clock-AF_DECnet", "clock-AF_NETBEUI"  , "clock-AF_SECURITY" ,
  "clock-AF_KEY"   , "clock-AF_NETLINK"  , "clock-AF_PACKET"   ,
  "clock-AF_ASH"   , "clock-AF_ECONET"   , "clock-AF_ATMSVC"   ,
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  "clock-AF_RDS"   , "clock-AF_SNA"      , "clock-AF_IRDA"     ,
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  "clock-AF_PPPOX" , "clock-AF_WANPIPE"  , "clock-AF_LLC"      ,
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  "clock-27"       , "clock-28"          , "clock-AF_CAN"      ,
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  "clock-AF_TIPC"  , "clock-AF_BLUETOOTH", "clock-AF_IUCV"     ,
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  "clock-AF_RXRPC" , "clock-AF_ISDN"     , "clock-AF_PHONET"   ,
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  "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG"      ,
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  "clock-AF_NFC"   , "clock-AF_MAX"
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};
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/*
 * sk_callback_lock 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];

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/* Take into consideration the size of the struct sk_buff overhead in the
 * determination of these values, since that is non-constant across
 * platforms.  This makes socket queueing behavior and performance
 * not depend upon such differences.
 */
#define _SK_MEM_PACKETS		256
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#define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
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#define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
#define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)

/* Run time adjustable parameters. */
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__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
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EXPORT_SYMBOL(sysctl_wmem_max);
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__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
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EXPORT_SYMBOL(sysctl_rmem_max);
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__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
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/* Maximal space eaten by iovec or ancillary data plus some space */
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int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
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EXPORT_SYMBOL(sysctl_optmem_max);
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#if defined(CONFIG_CGROUPS)
#if !defined(CONFIG_NET_CLS_CGROUP)
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int net_cls_subsys_id = -1;
EXPORT_SYMBOL_GPL(net_cls_subsys_id);
#endif
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#if !defined(CONFIG_NETPRIO_CGROUP)
int net_prio_subsys_id = -1;
EXPORT_SYMBOL_GPL(net_prio_subsys_id);
#endif
#endif
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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;
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	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
		return -EDOM;
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	if (tv.tv_sec < 0) {
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		static int warned __read_mostly;

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		*timeo_p = 0;
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		if (warned < 10 && net_ratelimit()) {
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			warned++;
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			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
				__func__, current->comm, task_pid_nr(current));
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		}
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		return 0;
	}
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	*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 + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
	return 0;
}

static void sock_warn_obsolete_bsdism(const char *name)
{
	static int warned;
	static char warncomm[TASK_COMM_LEN];
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	if (strcmp(warncomm, current->comm) && warned < 5) {
		strcpy(warncomm,  current->comm);
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		pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
			warncomm, name);
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		warned++;
	}
}

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#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))

static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
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{
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	if (sk->sk_flags & flags) {
		sk->sk_flags &= ~flags;
		if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP))
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			net_disable_timestamp();
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	}
}


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int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
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	int err;
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	int skb_len;
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	unsigned long flags;
	struct sk_buff_head *list = &sk->sk_receive_queue;
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	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
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		atomic_inc(&sk->sk_drops);
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		trace_sock_rcvqueue_full(sk, skb);
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		return -ENOMEM;
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	}

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	err = sk_filter(sk, skb);
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	if (err)
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		return err;
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	if (!sk_rmem_schedule(sk, skb->truesize)) {
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		atomic_inc(&sk->sk_drops);
		return -ENOBUFS;
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	}

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	skb->dev = NULL;
	skb_set_owner_r(skb, sk);
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	/* Cache the SKB length before we tack it onto the receive
	 * queue.  Once it is added it no longer belongs to us and
	 * may be freed by other threads of control pulling packets
	 * from the queue.
	 */
	skb_len = skb->len;

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	/* we escape from rcu protected region, make sure we dont leak
	 * a norefcounted dst
	 */
	skb_dst_force(skb);

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	spin_lock_irqsave(&list->lock, flags);
	skb->dropcount = atomic_read(&sk->sk_drops);
	__skb_queue_tail(list, skb);
	spin_unlock_irqrestore(&list->lock, flags);
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	if (!sock_flag(sk, SOCK_DEAD))
		sk->sk_data_ready(sk, skb_len);
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	return 0;
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}
EXPORT_SYMBOL(sock_queue_rcv_skb);

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int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
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{
	int rc = NET_RX_SUCCESS;

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	if (sk_filter(sk, skb))
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		goto discard_and_relse;

	skb->dev = NULL;

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	if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf)) {
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		atomic_inc(&sk->sk_drops);
		goto discard_and_relse;
	}
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	if (nested)
		bh_lock_sock_nested(sk);
	else
		bh_lock_sock(sk);
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	if (!sock_owned_by_user(sk)) {
		/*
		 * trylock + unlock semantics:
		 */
		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);

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		rc = sk_backlog_rcv(sk, skb);
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		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
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	} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
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		bh_unlock_sock(sk);
		atomic_inc(&sk->sk_drops);
		goto discard_and_relse;
	}

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	bh_unlock_sock(sk);
out:
	sock_put(sk);
	return rc;
discard_and_relse:
	kfree_skb(skb);
	goto out;
}
EXPORT_SYMBOL(sk_receive_skb);

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void sk_reset_txq(struct sock *sk)
{
	sk_tx_queue_clear(sk);
}
EXPORT_SYMBOL(sk_reset_txq);

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struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
{
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	struct dst_entry *dst = __sk_dst_get(sk);
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	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
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		sk_tx_queue_clear(sk);
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		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
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		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);

464 465 466 467
static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
{
	int ret = -ENOPROTOOPT;
#ifdef CONFIG_NETDEVICES
468
	struct net *net = sock_net(sk);
469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493
	char devname[IFNAMSIZ];
	int index;

	/* Sorry... */
	ret = -EPERM;
	if (!capable(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;

494 495
	index = 0;
	if (devname[0] != '\0') {
496
		struct net_device *dev;
497

498 499 500 501 502
		rcu_read_lock();
		dev = dev_get_by_name_rcu(net, devname);
		if (dev)
			index = dev->ifindex;
		rcu_read_unlock();
503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520
		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;
}

521 522 523 524 525 526 527 528
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);
}

L
Linus Torvalds 已提交
529 530 531 532 533 534
/*
 *	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,
535
		    char __user *optval, unsigned int optlen)
L
Linus Torvalds 已提交
536
{
E
Eric Dumazet 已提交
537
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
538 539 540 541
	int val;
	int valbool;
	struct linger ling;
	int ret = 0;
542

L
Linus Torvalds 已提交
543 544 545 546
	/*
	 *	Options without arguments
	 */

547 548 549
	if (optname == SO_BINDTODEVICE)
		return sock_bindtodevice(sk, optval, optlen);

550 551
	if (optlen < sizeof(int))
		return -EINVAL;
552

L
Linus Torvalds 已提交
553 554
	if (get_user(val, (int __user *)optval))
		return -EFAULT;
555

E
Eric Dumazet 已提交
556
	valbool = val ? 1 : 0;
L
Linus Torvalds 已提交
557 558 559

	lock_sock(sk);

E
Eric Dumazet 已提交
560
	switch (optname) {
561
	case SO_DEBUG:
E
Eric Dumazet 已提交
562
		if (val && !capable(CAP_NET_ADMIN))
563
			ret = -EACCES;
E
Eric Dumazet 已提交
564
		else
565
			sock_valbool_flag(sk, SOCK_DBG, valbool);
566 567
		break;
	case SO_REUSEADDR:
568
		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
569 570
		break;
	case SO_TYPE:
571
	case SO_PROTOCOL:
572
	case SO_DOMAIN:
573 574 575 576
	case SO_ERROR:
		ret = -ENOPROTOOPT;
		break;
	case SO_DONTROUTE:
577
		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
578 579 580 581 582 583
		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
584 585 586 587 588
		 * 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);
589
set_sndbuf:
590
		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
591 592
		sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
		/* Wake up sending tasks if we upped the value. */
593 594
		sk->sk_write_space(sk);
		break;
L
Linus Torvalds 已提交
595

596 597 598 599 600 601
	case SO_SNDBUFFORCE:
		if (!capable(CAP_NET_ADMIN)) {
			ret = -EPERM;
			break;
		}
		goto set_sndbuf;
602

603 604
	case SO_RCVBUF:
		/* Don't error on this BSD doesn't and if you think
605 606 607 608 609
		 * 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);
610
set_rcvbuf:
611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626
		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.
		 */
627
		sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
628 629 630 631 632
		break;

	case SO_RCVBUFFORCE:
		if (!capable(CAP_NET_ADMIN)) {
			ret = -EPERM;
L
Linus Torvalds 已提交
633
			break;
634 635
		}
		goto set_rcvbuf;
L
Linus Torvalds 已提交
636

637
	case SO_KEEPALIVE:
L
Linus Torvalds 已提交
638
#ifdef CONFIG_INET
639 640
		if (sk->sk_protocol == IPPROTO_TCP)
			tcp_set_keepalive(sk, valbool);
L
Linus Torvalds 已提交
641
#endif
642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662
		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 = valbool;
		break;

	case SO_PRIORITY:
		if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
			sk->sk_priority = val;
		else
			ret = -EPERM;
		break;

	case SO_LINGER:
		if (optlen < sizeof(ling)) {
			ret = -EINVAL;	/* 1003.1g */
L
Linus Torvalds 已提交
663
			break;
664
		}
E
Eric Dumazet 已提交
665
		if (copy_from_user(&ling, optval, sizeof(ling))) {
666
			ret = -EFAULT;
L
Linus Torvalds 已提交
667
			break;
668 669 670 671
		}
		if (!ling.l_onoff)
			sock_reset_flag(sk, SOCK_LINGER);
		else {
L
Linus Torvalds 已提交
672
#if (BITS_PER_LONG == 32)
673 674
			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
L
Linus Torvalds 已提交
675
			else
676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693
#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:
694
	case SO_TIMESTAMPNS:
695
		if (valbool)  {
696 697 698 699
			if (optname == SO_TIMESTAMP)
				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
			else
				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
700
			sock_set_flag(sk, SOCK_RCVTSTAMP);
701
			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
702
		} else {
703
			sock_reset_flag(sk, SOCK_RCVTSTAMP);
704 705
			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
		}
706 707
		break;

708 709
	case SO_TIMESTAMPING:
		if (val & ~SOF_TIMESTAMPING_MASK) {
710
			ret = -EINVAL;
711 712 713 714 715 716 717 718 719 720 721 722 723
			break;
		}
		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE,
				  val & SOF_TIMESTAMPING_TX_HARDWARE);
		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE,
				  val & SOF_TIMESTAMPING_TX_SOFTWARE);
		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE,
				  val & SOF_TIMESTAMPING_RX_HARDWARE);
		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
			sock_enable_timestamp(sk,
					      SOCK_TIMESTAMPING_RX_SOFTWARE);
		else
			sock_disable_timestamp(sk,
E
Eric Dumazet 已提交
724
					       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
725 726 727 728 729 730 731 732
		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE,
				  val & SOF_TIMESTAMPING_SOFTWARE);
		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE,
				  val & SOF_TIMESTAMPING_SYS_HARDWARE);
		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE,
				  val & SOF_TIMESTAMPING_RAW_HARDWARE);
		break;

733 734 735 736 737 738 739 740 741 742 743 744 745
	case SO_RCVLOWAT:
		if (val < 0)
			val = INT_MAX;
		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;
L
Linus Torvalds 已提交
746

747 748 749 750
	case SO_ATTACH_FILTER:
		ret = -EINVAL;
		if (optlen == sizeof(struct sock_fprog)) {
			struct sock_fprog fprog;
L
Linus Torvalds 已提交
751

752 753
			ret = -EFAULT;
			if (copy_from_user(&fprog, optval, sizeof(fprog)))
L
Linus Torvalds 已提交
754
				break;
755 756 757 758 759 760

			ret = sk_attach_filter(&fprog, sk);
		}
		break;

	case SO_DETACH_FILTER:
761
		ret = sk_detach_filter(sk);
762
		break;
L
Linus Torvalds 已提交
763

764 765 766 767 768 769
	case SO_PASSSEC:
		if (valbool)
			set_bit(SOCK_PASSSEC, &sock->flags);
		else
			clear_bit(SOCK_PASSSEC, &sock->flags);
		break;
770 771 772
	case SO_MARK:
		if (!capable(CAP_NET_ADMIN))
			ret = -EPERM;
E
Eric Dumazet 已提交
773
		else
774 775
			sk->sk_mark = val;
		break;
C
Catherine Zhang 已提交
776

L
Linus Torvalds 已提交
777 778
		/* We implement the SO_SNDLOWAT etc to
		   not be settable (1003.1g 5.3) */
779
	case SO_RXQ_OVFL:
780
		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
781
		break;
782 783 784 785 786

	case SO_WIFI_STATUS:
		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
		break;

787 788 789 790 791 792
	case SO_PEEK_OFF:
		if (sock->ops->set_peek_off)
			sock->ops->set_peek_off(sk, val);
		else
			ret = -EOPNOTSUPP;
		break;
793 794 795 796 797

	case SO_NOFCS:
		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
		break;

798 799 800
	default:
		ret = -ENOPROTOOPT;
		break;
801
	}
L
Linus Torvalds 已提交
802 803 804
	release_sock(sk);
	return ret;
}
E
Eric Dumazet 已提交
805
EXPORT_SYMBOL(sock_setsockopt);
L
Linus Torvalds 已提交
806 807


808 809 810 811 812 813 814 815
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();

816 817
		ucred->uid = from_kuid(current_ns, cred->euid);
		ucred->gid = from_kgid(current_ns, cred->egid);
818 819
	}
}
820
EXPORT_SYMBOL_GPL(cred_to_ucred);
821

L
Linus Torvalds 已提交
822 823 824 825
int sock_getsockopt(struct socket *sock, int level, int optname,
		    char __user *optval, int __user *optlen)
{
	struct sock *sk = sock->sk;
826

827
	union {
828 829
		int val;
		struct linger ling;
L
Linus Torvalds 已提交
830 831
		struct timeval tm;
	} v;
832

833
	int lv = sizeof(int);
L
Linus Torvalds 已提交
834
	int len;
835

836
	if (get_user(len, optlen))
837
		return -EFAULT;
838
	if (len < 0)
L
Linus Torvalds 已提交
839
		return -EINVAL;
840

841
	memset(&v, 0, sizeof(v));
842

E
Eric Dumazet 已提交
843
	switch (optname) {
844 845 846 847 848 849 850 851 852
	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:
E
Eric Dumazet 已提交
853
		v.val = sock_flag(sk, SOCK_BROADCAST);
854 855 856 857 858 859 860 861 862 863 864 865 866 867 868
		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_KEEPALIVE:
E
Eric Dumazet 已提交
869
		v.val = sock_flag(sk, SOCK_KEEPOPEN);
870 871 872 873 874 875
		break;

	case SO_TYPE:
		v.val = sk->sk_type;
		break;

876 877 878 879
	case SO_PROTOCOL:
		v.val = sk->sk_protocol;
		break;

880 881 882 883
	case SO_DOMAIN:
		v.val = sk->sk_family;
		break;

884 885
	case SO_ERROR:
		v.val = -sock_error(sk);
E
Eric Dumazet 已提交
886
		if (v.val == 0)
887 888 889 890
			v.val = xchg(&sk->sk_err_soft, 0);
		break;

	case SO_OOBINLINE:
E
Eric Dumazet 已提交
891
		v.val = sock_flag(sk, SOCK_URGINLINE);
892 893 894 895 896 897 898 899 900 901 902 903
		break;

	case SO_NO_CHECK:
		v.val = sk->sk_no_check;
		break;

	case SO_PRIORITY:
		v.val = sk->sk_priority;
		break;

	case SO_LINGER:
		lv		= sizeof(v.ling);
E
Eric Dumazet 已提交
904
		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
905 906 907 908 909 910 911 912
		v.ling.l_linger	= sk->sk_lingertime / HZ;
		break;

	case SO_BSDCOMPAT:
		sock_warn_obsolete_bsdism("getsockopt");
		break;

	case SO_TIMESTAMP:
913 914 915 916 917 918
		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
				!sock_flag(sk, SOCK_RCVTSTAMPNS);
		break;

	case SO_TIMESTAMPNS:
		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
919 920
		break;

921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938
	case SO_TIMESTAMPING:
		v.val = 0;
		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
			v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
			v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
			v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
			v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
		if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
			v.val |= SOF_TIMESTAMPING_SOFTWARE;
		if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
			v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
		if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
			v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
		break;

939
	case SO_RCVTIMEO:
E
Eric Dumazet 已提交
940
		lv = sizeof(struct timeval);
941 942 943 944 945 946 947 948 949 950
		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) * 1000000) / HZ;
		}
		break;

	case SO_SNDTIMEO:
E
Eric Dumazet 已提交
951
		lv = sizeof(struct timeval);
952 953 954 955 956 957 958 959
		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) * 1000000) / HZ;
		}
		break;
L
Linus Torvalds 已提交
960

961 962 963
	case SO_RCVLOWAT:
		v.val = sk->sk_rcvlowat;
		break;
L
Linus Torvalds 已提交
964

965
	case SO_SNDLOWAT:
E
Eric Dumazet 已提交
966
		v.val = 1;
967
		break;
L
Linus Torvalds 已提交
968

969
	case SO_PASSCRED:
970
		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
971
		break;
L
Linus Torvalds 已提交
972

973
	case SO_PEERCRED:
974 975 976 977 978 979
	{
		struct ucred peercred;
		if (len > sizeof(peercred))
			len = sizeof(peercred);
		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
		if (copy_to_user(optval, &peercred, len))
980 981
			return -EFAULT;
		goto lenout;
982
	}
L
Linus Torvalds 已提交
983

984 985 986 987 988 989 990 991 992 993 994 995
	case SO_PEERNAME:
	{
		char address[128];

		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
			return -ENOTCONN;
		if (lv < len)
			return -EINVAL;
		if (copy_to_user(optval, address, len))
			return -EFAULT;
		goto lenout;
	}
L
Linus Torvalds 已提交
996

997 998 999 1000 1001 1002
	/* 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;
L
Linus Torvalds 已提交
1003

1004
	case SO_PASSSEC:
1005
		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1006
		break;
C
Catherine Zhang 已提交
1007

1008 1009
	case SO_PEERSEC:
		return security_socket_getpeersec_stream(sock, optval, optlen, len);
L
Linus Torvalds 已提交
1010

1011 1012 1013 1014
	case SO_MARK:
		v.val = sk->sk_mark;
		break;

1015
	case SO_RXQ_OVFL:
E
Eric Dumazet 已提交
1016
		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1017 1018
		break;

1019
	case SO_WIFI_STATUS:
E
Eric Dumazet 已提交
1020
		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1021 1022
		break;

1023 1024 1025 1026 1027 1028
	case SO_PEEK_OFF:
		if (!sock->ops->set_peek_off)
			return -EOPNOTSUPP;

		v.val = sk->sk_peek_off;
		break;
1029
	case SO_NOFCS:
E
Eric Dumazet 已提交
1030
		v.val = sock_flag(sk, SOCK_NOFCS);
1031
		break;
1032 1033
	default:
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
1034
	}
1035

L
Linus Torvalds 已提交
1036 1037 1038 1039 1040
	if (len > lv)
		len = lv;
	if (copy_to_user(optval, &v, len))
		return -EFAULT;
lenout:
1041 1042 1043
	if (put_user(len, optlen))
		return -EFAULT;
	return 0;
L
Linus Torvalds 已提交
1044 1045
}

I
Ingo Molnar 已提交
1046 1047 1048 1049 1050
/*
 * Initialize an sk_lock.
 *
 * (We also register the sk_lock with the lock validator.)
 */
D
Dave Jones 已提交
1051
static inline void sock_lock_init(struct sock *sk)
I
Ingo Molnar 已提交
1052
{
1053 1054 1055 1056 1057
	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);
I
Ingo Molnar 已提交
1058 1059
}

E
Eric Dumazet 已提交
1060 1061 1062
/*
 * 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.
1063
 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
E
Eric Dumazet 已提交
1064
 */
1065 1066 1067 1068 1069
static void sock_copy(struct sock *nsk, const struct sock *osk)
{
#ifdef CONFIG_SECURITY_NETWORK
	void *sptr = nsk->sk_security;
#endif
1070 1071 1072 1073 1074
	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));

1075 1076 1077 1078 1079 1080
#ifdef CONFIG_SECURITY_NETWORK
	nsk->sk_security = sptr;
	security_sk_clone(osk, nsk);
#endif
}

1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110
/*
 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
 * un-modified. Special care is taken when initializing object to zero.
 */
static inline void sk_prot_clear_nulls(struct sock *sk, int size)
{
	if (offsetof(struct sock, sk_node.next) != 0)
		memset(sk, 0, offsetof(struct sock, sk_node.next));
	memset(&sk->sk_node.pprev, 0,
	       size - offsetof(struct sock, sk_node.pprev));
}

void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
{
	unsigned long nulls1, nulls2;

	nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
	nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
	if (nulls1 > nulls2)
		swap(nulls1, nulls2);

	if (nulls1 != 0)
		memset((char *)sk, 0, nulls1);
	memset((char *)sk + nulls1 + sizeof(void *), 0,
	       nulls2 - nulls1 - sizeof(void *));
	memset((char *)sk + nulls2 + sizeof(void *), 0,
	       size - nulls2 - sizeof(void *));
}
EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);

1111 1112
static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
		int family)
1113 1114 1115 1116 1117
{
	struct sock *sk;
	struct kmem_cache *slab;

	slab = prot->slab;
1118 1119 1120 1121 1122
	if (slab != NULL) {
		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
		if (!sk)
			return sk;
		if (priority & __GFP_ZERO) {
1123 1124 1125 1126
			if (prot->clear_sk)
				prot->clear_sk(sk, prot->obj_size);
			else
				sk_prot_clear_nulls(sk, prot->obj_size);
1127
		}
1128
	} else
1129 1130
		sk = kmalloc(prot->obj_size, priority);

1131
	if (sk != NULL) {
1132 1133
		kmemcheck_annotate_bitfield(sk, flags);

1134 1135 1136 1137 1138
		if (security_sk_alloc(sk, family, priority))
			goto out_free;

		if (!try_module_get(prot->owner))
			goto out_free_sec;
K
Krishna Kumar 已提交
1139
		sk_tx_queue_clear(sk);
1140 1141
	}

1142
	return sk;
1143 1144 1145 1146 1147 1148 1149 1150 1151

out_free_sec:
	security_sk_free(sk);
out_free:
	if (slab != NULL)
		kmem_cache_free(slab, sk);
	else
		kfree(sk);
	return NULL;
1152 1153 1154 1155 1156
}

static void sk_prot_free(struct proto *prot, struct sock *sk)
{
	struct kmem_cache *slab;
1157
	struct module *owner;
1158

1159
	owner = prot->owner;
1160
	slab = prot->slab;
1161 1162

	security_sk_free(sk);
1163 1164 1165 1166
	if (slab != NULL)
		kmem_cache_free(slab, sk);
	else
		kfree(sk);
1167
	module_put(owner);
1168 1169
}

1170 1171 1172
#ifdef CONFIG_CGROUPS
void sock_update_classid(struct sock *sk)
{
1173
	u32 classid;
1174

1175 1176 1177
	rcu_read_lock();  /* doing current task, which cannot vanish. */
	classid = task_cls_classid(current);
	rcu_read_unlock();
1178 1179 1180
	if (classid && classid != sk->sk_classid)
		sk->sk_classid = classid;
}
1181
EXPORT_SYMBOL(sock_update_classid);
1182 1183 1184 1185 1186

void sock_update_netprioidx(struct sock *sk)
{
	if (in_interrupt())
		return;
1187 1188

	sk->sk_cgrp_prioidx = task_netprioidx(current);
1189 1190
}
EXPORT_SYMBOL_GPL(sock_update_netprioidx);
1191 1192
#endif

L
Linus Torvalds 已提交
1193 1194
/**
 *	sk_alloc - All socket objects are allocated here
1195
 *	@net: the applicable net namespace
1196 1197 1198
 *	@family: protocol family
 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
 *	@prot: struct proto associated with this new sock instance
L
Linus Torvalds 已提交
1199
 */
1200
struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1201
		      struct proto *prot)
L
Linus Torvalds 已提交
1202
{
1203
	struct sock *sk;
L
Linus Torvalds 已提交
1204

1205
	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
L
Linus Torvalds 已提交
1206
	if (sk) {
1207 1208 1209 1210 1211 1212 1213
		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;
		sock_lock_init(sk);
1214
		sock_net_set(sk, get_net(net));
1215
		atomic_set(&sk->sk_wmem_alloc, 1);
1216 1217

		sock_update_classid(sk);
1218
		sock_update_netprioidx(sk);
L
Linus Torvalds 已提交
1219
	}
1220

1221
	return sk;
L
Linus Torvalds 已提交
1222
}
E
Eric Dumazet 已提交
1223
EXPORT_SYMBOL(sk_alloc);
L
Linus Torvalds 已提交
1224

1225
static void __sk_free(struct sock *sk)
L
Linus Torvalds 已提交
1226 1227 1228 1229 1230 1231
{
	struct sk_filter *filter;

	if (sk->sk_destruct)
		sk->sk_destruct(sk);

1232 1233
	filter = rcu_dereference_check(sk->sk_filter,
				       atomic_read(&sk->sk_wmem_alloc) == 0);
L
Linus Torvalds 已提交
1234
	if (filter) {
1235
		sk_filter_uncharge(sk, filter);
1236
		RCU_INIT_POINTER(sk->sk_filter, NULL);
L
Linus Torvalds 已提交
1237 1238
	}

E
Eric Dumazet 已提交
1239
	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
L
Linus Torvalds 已提交
1240 1241

	if (atomic_read(&sk->sk_omem_alloc))
J
Joe Perches 已提交
1242 1243
		pr_debug("%s: optmem leakage (%d bytes) detected\n",
			 __func__, atomic_read(&sk->sk_omem_alloc));
L
Linus Torvalds 已提交
1244

1245 1246 1247
	if (sk->sk_peer_cred)
		put_cred(sk->sk_peer_cred);
	put_pid(sk->sk_peer_pid);
1248
	put_net(sock_net(sk));
1249
	sk_prot_free(sk->sk_prot_creator, sk);
L
Linus Torvalds 已提交
1250
}
1251 1252 1253 1254

void sk_free(struct sock *sk)
{
	/*
L
Lucas De Marchi 已提交
1255
	 * We subtract one from sk_wmem_alloc and can know if
1256 1257 1258 1259 1260 1261
	 * some packets are still in some tx queue.
	 * If not null, sock_wfree() will call __sk_free(sk) later
	 */
	if (atomic_dec_and_test(&sk->sk_wmem_alloc))
		__sk_free(sk);
}
E
Eric Dumazet 已提交
1262
EXPORT_SYMBOL(sk_free);
L
Linus Torvalds 已提交
1263

1264
/*
L
Lucas De Marchi 已提交
1265 1266
 * Last sock_put should drop reference to sk->sk_net. It has already
 * been dropped in sk_change_net. Taking reference to stopping namespace
1267
 * is not an option.
L
Lucas De Marchi 已提交
1268
 * Take reference to a socket to remove it from hash _alive_ and after that
1269 1270 1271 1272 1273 1274 1275 1276 1277
 * destroy it in the context of init_net.
 */
void sk_release_kernel(struct sock *sk)
{
	if (sk == NULL || sk->sk_socket == NULL)
		return;

	sock_hold(sk);
	sock_release(sk->sk_socket);
1278
	release_net(sock_net(sk));
1279
	sock_net_set(sk, get_net(&init_net));
1280 1281
	sock_put(sk);
}
1282
EXPORT_SYMBOL(sk_release_kernel);
1283

1284 1285 1286 1287 1288 1289
static void sk_update_clone(const struct sock *sk, struct sock *newsk)
{
	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
		sock_update_memcg(newsk);
}

1290 1291 1292 1293 1294 1295 1296 1297
/**
 *	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)
1298
{
1299
	struct sock *newsk;
1300

1301
	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1302 1303 1304
	if (newsk != NULL) {
		struct sk_filter *filter;

1305
		sock_copy(newsk, sk);
1306 1307

		/* SANITY */
1308
		get_net(sock_net(newsk));
1309 1310 1311
		sk_node_init(&newsk->sk_node);
		sock_lock_init(newsk);
		bh_lock_sock(newsk);
1312
		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
Z
Zhu Yi 已提交
1313
		newsk->sk_backlog.len = 0;
1314 1315

		atomic_set(&newsk->sk_rmem_alloc, 0);
1316 1317 1318 1319
		/*
		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
		 */
		atomic_set(&newsk->sk_wmem_alloc, 1);
1320 1321 1322
		atomic_set(&newsk->sk_omem_alloc, 0);
		skb_queue_head_init(&newsk->sk_receive_queue);
		skb_queue_head_init(&newsk->sk_write_queue);
1323 1324 1325
#ifdef CONFIG_NET_DMA
		skb_queue_head_init(&newsk->sk_async_wait_queue);
#endif
1326

E
Eric Dumazet 已提交
1327
		spin_lock_init(&newsk->sk_dst_lock);
1328
		rwlock_init(&newsk->sk_callback_lock);
1329 1330 1331
		lockdep_set_class_and_name(&newsk->sk_callback_lock,
				af_callback_keys + newsk->sk_family,
				af_family_clock_key_strings[newsk->sk_family]);
1332 1333 1334 1335 1336 1337 1338 1339 1340 1341

		newsk->sk_dst_cache	= NULL;
		newsk->sk_wmem_queued	= 0;
		newsk->sk_forward_alloc = 0;
		newsk->sk_send_head	= NULL;
		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;

		sock_reset_flag(newsk, SOCK_DONE);
		skb_queue_head_init(&newsk->sk_error_queue);

1342
		filter = rcu_dereference_protected(newsk->sk_filter, 1);
1343 1344 1345 1346 1347 1348 1349
		if (filter != NULL)
			sk_filter_charge(newsk, filter);

		if (unlikely(xfrm_sk_clone_policy(newsk))) {
			/* It is still raw copy of parent, so invalidate
			 * destructor and make plain sk_free() */
			newsk->sk_destruct = NULL;
1350
			bh_unlock_sock(newsk);
1351 1352 1353 1354 1355 1356 1357
			sk_free(newsk);
			newsk = NULL;
			goto out;
		}

		newsk->sk_err	   = 0;
		newsk->sk_priority = 0;
E
Eric Dumazet 已提交
1358 1359 1360 1361 1362
		/*
		 * Before updating sk_refcnt, we must commit prior changes to memory
		 * (Documentation/RCU/rculist_nulls.txt for details)
		 */
		smp_wmb();
1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376
		atomic_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);
1377
		sk_set_socket(newsk, NULL);
1378
		newsk->sk_wq = NULL;
1379

1380 1381
		sk_update_clone(sk, newsk);

1382
		if (newsk->sk_prot->sockets_allocated)
1383
			sk_sockets_allocated_inc(newsk);
1384

E
Eric Dumazet 已提交
1385
		if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1386
			net_enable_timestamp();
1387 1388 1389 1390
	}
out:
	return newsk;
}
1391
EXPORT_SYMBOL_GPL(sk_clone_lock);
1392

1393 1394 1395 1396 1397
void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
{
	__sk_dst_set(sk, dst);
	sk->sk_route_caps = dst->dev->features;
	if (sk->sk_route_caps & NETIF_F_GSO)
1398
		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
E
Eric Dumazet 已提交
1399
	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1400
	if (sk_can_gso(sk)) {
1401
		if (dst->header_len) {
1402
			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1403
		} else {
1404
			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1405 1406
			sk->sk_gso_max_size = dst->dev->gso_max_size;
		}
1407 1408 1409 1410
	}
}
EXPORT_SYMBOL_GPL(sk_setup_caps);

L
Linus Torvalds 已提交
1411 1412
void __init sk_init(void)
{
1413
	if (totalram_pages <= 4096) {
L
Linus Torvalds 已提交
1414 1415 1416 1417
		sysctl_wmem_max = 32767;
		sysctl_rmem_max = 32767;
		sysctl_wmem_default = 32767;
		sysctl_rmem_default = 32767;
1418
	} else if (totalram_pages >= 131072) {
L
Linus Torvalds 已提交
1419 1420 1421 1422 1423 1424 1425 1426 1427 1428
		sysctl_wmem_max = 131071;
		sysctl_rmem_max = 131071;
	}
}

/*
 *	Simple resource managers for sockets.
 */


1429 1430
/*
 * Write buffer destructor automatically called from kfree_skb.
L
Linus Torvalds 已提交
1431 1432 1433 1434
 */
void sock_wfree(struct sk_buff *skb)
{
	struct sock *sk = skb->sk;
E
Eric Dumazet 已提交
1435
	unsigned int len = skb->truesize;
L
Linus Torvalds 已提交
1436

E
Eric Dumazet 已提交
1437 1438 1439 1440 1441 1442
	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
		/*
		 * Keep a reference on sk_wmem_alloc, this will be released
		 * after sk_write_space() call
		 */
		atomic_sub(len - 1, &sk->sk_wmem_alloc);
L
Linus Torvalds 已提交
1443
		sk->sk_write_space(sk);
E
Eric Dumazet 已提交
1444 1445
		len = 1;
	}
1446
	/*
E
Eric Dumazet 已提交
1447 1448
	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
	 * could not do because of in-flight packets
1449
	 */
E
Eric Dumazet 已提交
1450
	if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1451
		__sk_free(sk);
L
Linus Torvalds 已提交
1452
}
E
Eric Dumazet 已提交
1453
EXPORT_SYMBOL(sock_wfree);
L
Linus Torvalds 已提交
1454

1455 1456
/*
 * Read buffer destructor automatically called from kfree_skb.
L
Linus Torvalds 已提交
1457 1458 1459 1460
 */
void sock_rfree(struct sk_buff *skb)
{
	struct sock *sk = skb->sk;
E
Eric Dumazet 已提交
1461
	unsigned int len = skb->truesize;
L
Linus Torvalds 已提交
1462

E
Eric Dumazet 已提交
1463 1464
	atomic_sub(len, &sk->sk_rmem_alloc);
	sk_mem_uncharge(sk, len);
L
Linus Torvalds 已提交
1465
}
E
Eric Dumazet 已提交
1466
EXPORT_SYMBOL(sock_rfree);
L
Linus Torvalds 已提交
1467 1468 1469 1470 1471 1472


int sock_i_uid(struct sock *sk)
{
	int uid;

E
Eric Dumazet 已提交
1473
	read_lock_bh(&sk->sk_callback_lock);
L
Linus Torvalds 已提交
1474
	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
E
Eric Dumazet 已提交
1475
	read_unlock_bh(&sk->sk_callback_lock);
L
Linus Torvalds 已提交
1476 1477
	return uid;
}
E
Eric Dumazet 已提交
1478
EXPORT_SYMBOL(sock_i_uid);
L
Linus Torvalds 已提交
1479 1480 1481 1482 1483

unsigned long sock_i_ino(struct sock *sk)
{
	unsigned long ino;

E
Eric Dumazet 已提交
1484
	read_lock_bh(&sk->sk_callback_lock);
L
Linus Torvalds 已提交
1485
	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
E
Eric Dumazet 已提交
1486
	read_unlock_bh(&sk->sk_callback_lock);
L
Linus Torvalds 已提交
1487 1488
	return ino;
}
E
Eric Dumazet 已提交
1489
EXPORT_SYMBOL(sock_i_ino);
L
Linus Torvalds 已提交
1490 1491 1492 1493

/*
 * Allocate a skb from the socket's send buffer.
 */
V
Victor Fusco 已提交
1494
struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
A
Al Viro 已提交
1495
			     gfp_t priority)
L
Linus Torvalds 已提交
1496 1497
{
	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
E
Eric Dumazet 已提交
1498
		struct sk_buff *skb = alloc_skb(size, priority);
L
Linus Torvalds 已提交
1499 1500 1501 1502 1503 1504 1505
		if (skb) {
			skb_set_owner_w(skb, sk);
			return skb;
		}
	}
	return NULL;
}
E
Eric Dumazet 已提交
1506
EXPORT_SYMBOL(sock_wmalloc);
L
Linus Torvalds 已提交
1507 1508 1509

/*
 * Allocate a skb from the socket's receive buffer.
1510
 */
V
Victor Fusco 已提交
1511
struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
A
Al Viro 已提交
1512
			     gfp_t priority)
L
Linus Torvalds 已提交
1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523
{
	if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
		struct sk_buff *skb = alloc_skb(size, priority);
		if (skb) {
			skb_set_owner_r(skb, sk);
			return skb;
		}
	}
	return NULL;
}

1524
/*
L
Linus Torvalds 已提交
1525
 * Allocate a memory block from the socket's option memory buffer.
1526
 */
A
Al Viro 已提交
1527
void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
L
Linus Torvalds 已提交
1528
{
1529
	if ((unsigned int)size <= sysctl_optmem_max &&
L
Linus Torvalds 已提交
1530 1531 1532
	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
		void *mem;
		/* First do the add, to avoid the race if kmalloc
1533
		 * might sleep.
L
Linus Torvalds 已提交
1534 1535 1536 1537 1538 1539 1540 1541 1542
		 */
		atomic_add(size, &sk->sk_omem_alloc);
		mem = kmalloc(size, priority);
		if (mem)
			return mem;
		atomic_sub(size, &sk->sk_omem_alloc);
	}
	return NULL;
}
E
Eric Dumazet 已提交
1543
EXPORT_SYMBOL(sock_kmalloc);
L
Linus Torvalds 已提交
1544 1545 1546 1547 1548 1549 1550 1551 1552

/*
 * Free an option memory block.
 */
void sock_kfree_s(struct sock *sk, void *mem, int size)
{
	kfree(mem);
	atomic_sub(size, &sk->sk_omem_alloc);
}
E
Eric Dumazet 已提交
1553
EXPORT_SYMBOL(sock_kfree_s);
L
Linus Torvalds 已提交
1554 1555 1556 1557

/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
   I think, these locks should be removed for datagram sockets.
 */
E
Eric Dumazet 已提交
1558
static long sock_wait_for_wmem(struct sock *sk, long timeo)
L
Linus Torvalds 已提交
1559 1560 1561 1562 1563 1564 1565 1566 1567 1568
{
	DEFINE_WAIT(wait);

	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
	for (;;) {
		if (!timeo)
			break;
		if (signal_pending(current))
			break;
		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
E
Eric Dumazet 已提交
1569
		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
L
Linus Torvalds 已提交
1570 1571 1572 1573 1574 1575 1576 1577
		if (atomic_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);
	}
E
Eric Dumazet 已提交
1578
	finish_wait(sk_sleep(sk), &wait);
L
Linus Torvalds 已提交
1579 1580 1581 1582 1583 1584 1585 1586
	return timeo;
}


/*
 *	Generic send/receive buffer handlers
 */

H
Herbert Xu 已提交
1587 1588 1589
struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
				     unsigned long data_len, int noblock,
				     int *errcode)
L
Linus Torvalds 已提交
1590 1591
{
	struct sk_buff *skb;
A
Al Viro 已提交
1592
	gfp_t gfp_mask;
L
Linus Torvalds 已提交
1593 1594
	long timeo;
	int err;
1595 1596 1597 1598 1599
	int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;

	err = -EMSGSIZE;
	if (npages > MAX_SKB_FRAGS)
		goto failure;
L
Linus Torvalds 已提交
1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615

	gfp_mask = sk->sk_allocation;
	if (gfp_mask & __GFP_WAIT)
		gfp_mask |= __GFP_REPEAT;

	timeo = sock_sndtimeo(sk, noblock);
	while (1) {
		err = sock_error(sk);
		if (err != 0)
			goto failure;

		err = -EPIPE;
		if (sk->sk_shutdown & SEND_SHUTDOWN)
			goto failure;

		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1616
			skb = alloc_skb(header_len, gfp_mask);
L
Linus Torvalds 已提交
1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636
			if (skb) {
				int i;

				/* No pages, we're done... */
				if (!data_len)
					break;

				skb->truesize += data_len;
				skb_shinfo(skb)->nr_frags = npages;
				for (i = 0; i < npages; i++) {
					struct page *page;

					page = alloc_pages(sk->sk_allocation, 0);
					if (!page) {
						err = -ENOBUFS;
						skb_shinfo(skb)->nr_frags = i;
						kfree_skb(skb);
						goto failure;
					}

1637 1638 1639 1640 1641
					__skb_fill_page_desc(skb, i,
							page, 0,
							(data_len >= PAGE_SIZE ?
							 PAGE_SIZE :
							 data_len));
L
Linus Torvalds 已提交
1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669
					data_len -= PAGE_SIZE;
				}

				/* Full success... */
				break;
			}
			err = -ENOBUFS;
			goto failure;
		}
		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
		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_set_owner_w(skb, sk);
	return skb;

interrupted:
	err = sock_intr_errno(timeo);
failure:
	*errcode = err;
	return NULL;
}
H
Herbert Xu 已提交
1670
EXPORT_SYMBOL(sock_alloc_send_pskb);
L
Linus Torvalds 已提交
1671

1672
struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
L
Linus Torvalds 已提交
1673 1674 1675 1676
				    int noblock, int *errcode)
{
	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
}
E
Eric Dumazet 已提交
1677
EXPORT_SYMBOL(sock_alloc_send_skb);
L
Linus Torvalds 已提交
1678 1679

static void __lock_sock(struct sock *sk)
1680 1681
	__releases(&sk->sk_lock.slock)
	__acquires(&sk->sk_lock.slock)
L
Linus Torvalds 已提交
1682 1683 1684
{
	DEFINE_WAIT(wait);

1685
	for (;;) {
L
Linus Torvalds 已提交
1686 1687 1688 1689 1690
		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);
1691
		if (!sock_owned_by_user(sk))
L
Linus Torvalds 已提交
1692 1693 1694 1695 1696 1697
			break;
	}
	finish_wait(&sk->sk_lock.wq, &wait);
}

static void __release_sock(struct sock *sk)
1698 1699
	__releases(&sk->sk_lock.slock)
	__acquires(&sk->sk_lock.slock)
L
Linus Torvalds 已提交
1700 1701 1702 1703 1704 1705 1706 1707 1708 1709
{
	struct sk_buff *skb = sk->sk_backlog.head;

	do {
		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
		bh_unlock_sock(sk);

		do {
			struct sk_buff *next = skb->next;

1710
			prefetch(next);
E
Eric Dumazet 已提交
1711
			WARN_ON_ONCE(skb_dst_is_noref(skb));
L
Linus Torvalds 已提交
1712
			skb->next = NULL;
P
Peter Zijlstra 已提交
1713
			sk_backlog_rcv(sk, skb);
L
Linus Torvalds 已提交
1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726

			/*
			 * We are in process context here with softirqs
			 * disabled, use cond_resched_softirq() to preempt.
			 * This is safe to do because we've taken the backlog
			 * queue private:
			 */
			cond_resched_softirq();

			skb = next;
		} while (skb != NULL);

		bh_lock_sock(sk);
1727
	} while ((skb = sk->sk_backlog.head) != NULL);
Z
Zhu Yi 已提交
1728 1729 1730 1731 1732 1733

	/*
	 * Doing the zeroing here guarantee we can not loop forever
	 * while a wild producer attempts to flood us.
	 */
	sk->sk_backlog.len = 0;
L
Linus Torvalds 已提交
1734 1735 1736 1737
}

/**
 * sk_wait_data - wait for data to arrive at sk_receive_queue
1738 1739
 * @sk:    sock to wait on
 * @timeo: for how long
L
Linus Torvalds 已提交
1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750
 *
 * 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)
{
	int rc;
	DEFINE_WAIT(wait);

E
Eric Dumazet 已提交
1751
	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
L
Linus Torvalds 已提交
1752 1753 1754
	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
E
Eric Dumazet 已提交
1755
	finish_wait(sk_sleep(sk), &wait);
L
Linus Torvalds 已提交
1756 1757 1758 1759
	return rc;
}
EXPORT_SYMBOL(sk_wait_data);

1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773
/**
 *	__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)
{
	struct proto *prot = sk->sk_prot;
	int amt = sk_mem_pages(size);
E
Eric Dumazet 已提交
1774
	long allocated;
G
Glauber Costa 已提交
1775
	int parent_status = UNDER_LIMIT;
1776 1777

	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1778

G
Glauber Costa 已提交
1779
	allocated = sk_memory_allocated_add(sk, amt, &parent_status);
1780 1781

	/* Under limit. */
G
Glauber Costa 已提交
1782 1783
	if (parent_status == UNDER_LIMIT &&
			allocated <= sk_prot_mem_limits(sk, 0)) {
1784
		sk_leave_memory_pressure(sk);
1785 1786 1787
		return 1;
	}

G
Glauber Costa 已提交
1788 1789 1790
	/* Under pressure. (we or our parents) */
	if ((parent_status > SOFT_LIMIT) ||
			allocated > sk_prot_mem_limits(sk, 1))
1791
		sk_enter_memory_pressure(sk);
1792

G
Glauber Costa 已提交
1793 1794 1795
	/* Over hard limit (we or our parents) */
	if ((parent_status == OVER_LIMIT) ||
			(allocated > sk_prot_mem_limits(sk, 2)))
1796 1797 1798 1799 1800 1801
		goto suppress_allocation;

	/* guarantee minimum buffer size under pressure */
	if (kind == SK_MEM_RECV) {
		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
			return 1;
1802

1803 1804 1805 1806 1807 1808 1809 1810 1811
	} else { /* SK_MEM_SEND */
		if (sk->sk_type == SOCK_STREAM) {
			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
				return 1;
		} else if (atomic_read(&sk->sk_wmem_alloc) <
			   prot->sysctl_wmem[0])
				return 1;
	}

1812
	if (sk_has_memory_pressure(sk)) {
1813 1814
		int alloc;

1815
		if (!sk_under_memory_pressure(sk))
1816
			return 1;
1817 1818
		alloc = sk_sockets_allocated_read_positive(sk);
		if (sk_prot_mem_limits(sk, 2) > alloc *
1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836
		    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;
	}

1837 1838
	trace_sock_exceed_buf_limit(sk, prot, allocated);

1839 1840
	/* Alas. Undo changes. */
	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1841

1842
	sk_memory_allocated_sub(sk, amt);
1843

1844 1845 1846 1847 1848 1849 1850 1851 1852 1853
	return 0;
}
EXPORT_SYMBOL(__sk_mem_schedule);

/**
 *	__sk_reclaim - reclaim memory_allocated
 *	@sk: socket
 */
void __sk_mem_reclaim(struct sock *sk)
{
1854
	sk_memory_allocated_sub(sk,
1855
				sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT);
1856 1857
	sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;

1858 1859 1860
	if (sk_under_memory_pressure(sk) &&
	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
		sk_leave_memory_pressure(sk);
1861 1862 1863 1864
}
EXPORT_SYMBOL(__sk_mem_reclaim);


L
Linus Torvalds 已提交
1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875
/*
 * 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;
}
E
Eric Dumazet 已提交
1876
EXPORT_SYMBOL(sock_no_bind);
L
Linus Torvalds 已提交
1877

1878
int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
L
Linus Torvalds 已提交
1879 1880 1881 1882
		    int len, int flags)
{
	return -EOPNOTSUPP;
}
E
Eric Dumazet 已提交
1883
EXPORT_SYMBOL(sock_no_connect);
L
Linus Torvalds 已提交
1884 1885 1886 1887 1888

int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
{
	return -EOPNOTSUPP;
}
E
Eric Dumazet 已提交
1889
EXPORT_SYMBOL(sock_no_socketpair);
L
Linus Torvalds 已提交
1890 1891 1892 1893 1894

int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
{
	return -EOPNOTSUPP;
}
E
Eric Dumazet 已提交
1895
EXPORT_SYMBOL(sock_no_accept);
L
Linus Torvalds 已提交
1896

1897
int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
L
Linus Torvalds 已提交
1898 1899 1900 1901
		    int *len, int peer)
{
	return -EOPNOTSUPP;
}
E
Eric Dumazet 已提交
1902
EXPORT_SYMBOL(sock_no_getname);
L
Linus Torvalds 已提交
1903

E
Eric Dumazet 已提交
1904
unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
L
Linus Torvalds 已提交
1905 1906 1907
{
	return 0;
}
E
Eric Dumazet 已提交
1908
EXPORT_SYMBOL(sock_no_poll);
L
Linus Torvalds 已提交
1909 1910 1911 1912 1913

int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
	return -EOPNOTSUPP;
}
E
Eric Dumazet 已提交
1914
EXPORT_SYMBOL(sock_no_ioctl);
L
Linus Torvalds 已提交
1915 1916 1917 1918 1919

int sock_no_listen(struct socket *sock, int backlog)
{
	return -EOPNOTSUPP;
}
E
Eric Dumazet 已提交
1920
EXPORT_SYMBOL(sock_no_listen);
L
Linus Torvalds 已提交
1921 1922 1923 1924 1925

int sock_no_shutdown(struct socket *sock, int how)
{
	return -EOPNOTSUPP;
}
E
Eric Dumazet 已提交
1926
EXPORT_SYMBOL(sock_no_shutdown);
L
Linus Torvalds 已提交
1927 1928

int sock_no_setsockopt(struct socket *sock, int level, int optname,
1929
		    char __user *optval, unsigned int optlen)
L
Linus Torvalds 已提交
1930 1931 1932
{
	return -EOPNOTSUPP;
}
E
Eric Dumazet 已提交
1933
EXPORT_SYMBOL(sock_no_setsockopt);
L
Linus Torvalds 已提交
1934 1935 1936 1937 1938 1939

int sock_no_getsockopt(struct socket *sock, int level, int optname,
		    char __user *optval, int __user *optlen)
{
	return -EOPNOTSUPP;
}
E
Eric Dumazet 已提交
1940
EXPORT_SYMBOL(sock_no_getsockopt);
L
Linus Torvalds 已提交
1941 1942 1943 1944 1945 1946

int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
		    size_t len)
{
	return -EOPNOTSUPP;
}
E
Eric Dumazet 已提交
1947
EXPORT_SYMBOL(sock_no_sendmsg);
L
Linus Torvalds 已提交
1948 1949 1950 1951 1952 1953

int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
		    size_t len, int flags)
{
	return -EOPNOTSUPP;
}
E
Eric Dumazet 已提交
1954
EXPORT_SYMBOL(sock_no_recvmsg);
L
Linus Torvalds 已提交
1955 1956 1957 1958 1959 1960

int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
{
	/* Mirror missing mmap method error code */
	return -ENODEV;
}
E
Eric Dumazet 已提交
1961
EXPORT_SYMBOL(sock_no_mmap);
L
Linus Torvalds 已提交
1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974

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;
}
E
Eric Dumazet 已提交
1975
EXPORT_SYMBOL(sock_no_sendpage);
L
Linus Torvalds 已提交
1976 1977 1978 1979 1980 1981 1982

/*
 *	Default Socket Callbacks
 */

static void sock_def_wakeup(struct sock *sk)
{
1983 1984 1985 1986 1987 1988 1989
	struct socket_wq *wq;

	rcu_read_lock();
	wq = rcu_dereference(sk->sk_wq);
	if (wq_has_sleeper(wq))
		wake_up_interruptible_all(&wq->wait);
	rcu_read_unlock();
L
Linus Torvalds 已提交
1990 1991 1992 1993
}

static void sock_def_error_report(struct sock *sk)
{
1994 1995 1996 1997 1998 1999
	struct socket_wq *wq;

	rcu_read_lock();
	wq = rcu_dereference(sk->sk_wq);
	if (wq_has_sleeper(wq))
		wake_up_interruptible_poll(&wq->wait, POLLERR);
2000
	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2001
	rcu_read_unlock();
L
Linus Torvalds 已提交
2002 2003 2004 2005
}

static void sock_def_readable(struct sock *sk, int len)
{
2006 2007 2008 2009 2010
	struct socket_wq *wq;

	rcu_read_lock();
	wq = rcu_dereference(sk->sk_wq);
	if (wq_has_sleeper(wq))
2011
		wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2012
						POLLRDNORM | POLLRDBAND);
2013
	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2014
	rcu_read_unlock();
L
Linus Torvalds 已提交
2015 2016 2017 2018
}

static void sock_def_write_space(struct sock *sk)
{
2019 2020 2021
	struct socket_wq *wq;

	rcu_read_lock();
L
Linus Torvalds 已提交
2022 2023 2024 2025

	/* Do not wake up a writer until he can make "significant"
	 * progress.  --DaveM
	 */
2026
	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2027 2028 2029
		wq = rcu_dereference(sk->sk_wq);
		if (wq_has_sleeper(wq))
			wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2030
						POLLWRNORM | POLLWRBAND);
L
Linus Torvalds 已提交
2031 2032 2033

		/* Should agree with poll, otherwise some programs break */
		if (sock_writeable(sk))
2034
			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
L
Linus Torvalds 已提交
2035 2036
	}

2037
	rcu_read_unlock();
L
Linus Torvalds 已提交
2038 2039 2040 2041
}

static void sock_def_destruct(struct sock *sk)
{
J
Jesper Juhl 已提交
2042
	kfree(sk->sk_protinfo);
L
Linus Torvalds 已提交
2043 2044 2045 2046 2047 2048
}

void sk_send_sigurg(struct sock *sk)
{
	if (sk->sk_socket && sk->sk_socket->file)
		if (send_sigurg(&sk->sk_socket->file->f_owner))
2049
			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
L
Linus Torvalds 已提交
2050
}
E
Eric Dumazet 已提交
2051
EXPORT_SYMBOL(sk_send_sigurg);
L
Linus Torvalds 已提交
2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072

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 (timer_pending(timer) && del_timer(timer))
		__sock_put(sk);
}
EXPORT_SYMBOL(sk_stop_timer);

void sock_init_data(struct socket *sock, 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);
2073 2074 2075
#ifdef CONFIG_NET_DMA
	skb_queue_head_init(&sk->sk_async_wait_queue);
#endif
L
Linus Torvalds 已提交
2076 2077 2078 2079

	sk->sk_send_head	=	NULL;

	init_timer(&sk->sk_timer);
2080

L
Linus Torvalds 已提交
2081 2082 2083 2084
	sk->sk_allocation	=	GFP_KERNEL;
	sk->sk_rcvbuf		=	sysctl_rmem_default;
	sk->sk_sndbuf		=	sysctl_wmem_default;
	sk->sk_state		=	TCP_CLOSE;
2085
	sk_set_socket(sk, sock);
L
Linus Torvalds 已提交
2086 2087 2088

	sock_set_flag(sk, SOCK_ZAPPED);

2089
	if (sock) {
L
Linus Torvalds 已提交
2090
		sk->sk_type	=	sock->type;
2091
		sk->sk_wq	=	sock->wq;
L
Linus Torvalds 已提交
2092 2093
		sock->sk	=	sk;
	} else
2094
		sk->sk_wq	=	NULL;
L
Linus Torvalds 已提交
2095

E
Eric Dumazet 已提交
2096
	spin_lock_init(&sk->sk_dst_lock);
L
Linus Torvalds 已提交
2097
	rwlock_init(&sk->sk_callback_lock);
2098 2099 2100
	lockdep_set_class_and_name(&sk->sk_callback_lock,
			af_callback_keys + sk->sk_family,
			af_family_clock_key_strings[sk->sk_family]);
L
Linus Torvalds 已提交
2101 2102 2103 2104 2105 2106 2107 2108 2109

	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_sndmsg_page	=	NULL;
	sk->sk_sndmsg_off	=	0;
2110
	sk->sk_peek_off		=	-1;
L
Linus Torvalds 已提交
2111

2112 2113
	sk->sk_peer_pid 	=	NULL;
	sk->sk_peer_cred	=	NULL;
L
Linus Torvalds 已提交
2114 2115 2116 2117 2118
	sk->sk_write_pending	=	0;
	sk->sk_rcvlowat		=	1;
	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;

2119
	sk->sk_stamp = ktime_set(-1L, 0);
L
Linus Torvalds 已提交
2120

E
Eric Dumazet 已提交
2121 2122 2123 2124 2125
	/*
	 * Before updating sk_refcnt, we must commit prior changes to memory
	 * (Documentation/RCU/rculist_nulls.txt for details)
	 */
	smp_wmb();
L
Linus Torvalds 已提交
2126
	atomic_set(&sk->sk_refcnt, 1);
W
Wang Chen 已提交
2127
	atomic_set(&sk->sk_drops, 0);
L
Linus Torvalds 已提交
2128
}
E
Eric Dumazet 已提交
2129
EXPORT_SYMBOL(sock_init_data);
L
Linus Torvalds 已提交
2130

H
Harvey Harrison 已提交
2131
void lock_sock_nested(struct sock *sk, int subclass)
L
Linus Torvalds 已提交
2132 2133
{
	might_sleep();
I
Ingo Molnar 已提交
2134
	spin_lock_bh(&sk->sk_lock.slock);
2135
	if (sk->sk_lock.owned)
L
Linus Torvalds 已提交
2136
		__lock_sock(sk);
2137
	sk->sk_lock.owned = 1;
I
Ingo Molnar 已提交
2138 2139 2140 2141
	spin_unlock(&sk->sk_lock.slock);
	/*
	 * The sk_lock has mutex_lock() semantics here:
	 */
2142
	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
I
Ingo Molnar 已提交
2143
	local_bh_enable();
L
Linus Torvalds 已提交
2144
}
2145
EXPORT_SYMBOL(lock_sock_nested);
L
Linus Torvalds 已提交
2146

H
Harvey Harrison 已提交
2147
void release_sock(struct sock *sk)
L
Linus Torvalds 已提交
2148
{
I
Ingo Molnar 已提交
2149 2150 2151 2152 2153 2154
	/*
	 * The sk_lock has mutex_unlock() semantics:
	 */
	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);

	spin_lock_bh(&sk->sk_lock.slock);
L
Linus Torvalds 已提交
2155 2156
	if (sk->sk_backlog.tail)
		__release_sock(sk);
2157
	sk->sk_lock.owned = 0;
I
Ingo Molnar 已提交
2158 2159 2160
	if (waitqueue_active(&sk->sk_lock.wq))
		wake_up(&sk->sk_lock.wq);
	spin_unlock_bh(&sk->sk_lock.slock);
L
Linus Torvalds 已提交
2161 2162 2163
}
EXPORT_SYMBOL(release_sock);

2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196
/**
 * 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);

L
Linus Torvalds 已提交
2197
int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2198
{
2199
	struct timeval tv;
L
Linus Torvalds 已提交
2200
	if (!sock_flag(sk, SOCK_TIMESTAMP))
2201
		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2202 2203
	tv = ktime_to_timeval(sk->sk_stamp);
	if (tv.tv_sec == -1)
L
Linus Torvalds 已提交
2204
		return -ENOENT;
2205 2206 2207 2208 2209
	if (tv.tv_sec == 0) {
		sk->sk_stamp = ktime_get_real();
		tv = ktime_to_timeval(sk->sk_stamp);
	}
	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2210
}
L
Linus Torvalds 已提交
2211 2212
EXPORT_SYMBOL(sock_get_timestamp);

2213 2214 2215 2216
int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
{
	struct timespec ts;
	if (!sock_flag(sk, SOCK_TIMESTAMP))
2217
		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228
	ts = ktime_to_timespec(sk->sk_stamp);
	if (ts.tv_sec == -1)
		return -ENOENT;
	if (ts.tv_sec == 0) {
		sk->sk_stamp = ktime_get_real();
		ts = ktime_to_timespec(sk->sk_stamp);
	}
	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
}
EXPORT_SYMBOL(sock_get_timestampns);

2229
void sock_enable_timestamp(struct sock *sk, int flag)
2230
{
2231
	if (!sock_flag(sk, flag)) {
E
Eric Dumazet 已提交
2232 2233
		unsigned long previous_flags = sk->sk_flags;

2234 2235 2236 2237 2238 2239
		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
		 */
E
Eric Dumazet 已提交
2240
		if (!(previous_flags & SK_FLAGS_TIMESTAMP))
2241
			net_enable_timestamp();
L
Linus Torvalds 已提交
2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260
	}
}

/*
 *	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);

2261
#ifdef CONFIG_COMPAT
2262 2263
int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
				  char __user *optval, int __user *optlen)
2264 2265 2266
{
	struct sock *sk = sock->sk;

2267
	if (sk->sk_prot->compat_getsockopt != NULL)
2268 2269
		return sk->sk_prot->compat_getsockopt(sk, level, optname,
						      optval, optlen);
2270 2271 2272 2273 2274
	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
}
EXPORT_SYMBOL(compat_sock_common_getsockopt);
#endif

L
Linus Torvalds 已提交
2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293
int sock_common_recvmsg(struct kiocb *iocb, 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(iocb, 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,
2294
			   char __user *optval, unsigned int optlen)
L
Linus Torvalds 已提交
2295 2296 2297 2298 2299 2300 2301
{
	struct sock *sk = sock->sk;

	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
}
EXPORT_SYMBOL(sock_common_setsockopt);

2302
#ifdef CONFIG_COMPAT
2303
int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2304
				  char __user *optval, unsigned int optlen)
2305 2306 2307
{
	struct sock *sk = sock->sk;

2308 2309 2310
	if (sk->sk_prot->compat_setsockopt != NULL)
		return sk->sk_prot->compat_setsockopt(sk, level, optname,
						      optval, optlen);
2311 2312 2313 2314 2315
	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
}
EXPORT_SYMBOL(compat_sock_common_setsockopt);
#endif

L
Linus Torvalds 已提交
2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346
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);

2347
	sk_refcnt_debug_release(sk);
L
Linus Torvalds 已提交
2348 2349 2350 2351
	sock_put(sk);
}
EXPORT_SYMBOL(sk_common_release);

2352 2353
#ifdef CONFIG_PROC_FS
#define PROTO_INUSE_NR	64	/* should be enough for the first time */
2354 2355 2356
struct prot_inuse {
	int val[PROTO_INUSE_NR];
};
2357 2358

static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2359 2360 2361 2362

#ifdef CONFIG_NET_NS
void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
{
E
Eric Dumazet 已提交
2363
	__this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378
}
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.inuse, cpu)->val[idx];

	return res >= 0 ? res : 0;
}
EXPORT_SYMBOL_GPL(sock_prot_inuse_get);

2379
static int __net_init sock_inuse_init_net(struct net *net)
2380 2381 2382 2383 2384
{
	net->core.inuse = alloc_percpu(struct prot_inuse);
	return net->core.inuse ? 0 : -ENOMEM;
}

2385
static void __net_exit sock_inuse_exit_net(struct net *net)
2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404
{
	free_percpu(net->core.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);
#else
2405 2406
static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);

2407
void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2408
{
E
Eric Dumazet 已提交
2409
	__this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2410 2411 2412
}
EXPORT_SYMBOL_GPL(sock_prot_inuse_add);

2413
int sock_prot_inuse_get(struct net *net, struct proto *prot)
2414 2415 2416 2417 2418 2419 2420 2421 2422 2423
{
	int cpu, idx = prot->inuse_idx;
	int res = 0;

	for_each_possible_cpu(cpu)
		res += per_cpu(prot_inuse, cpu).val[idx];

	return res >= 0 ? res : 0;
}
EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2424
#endif
2425 2426 2427 2428 2429 2430

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)) {
J
Joe Perches 已提交
2431
		pr_err("PROTO_INUSE_NR exhausted\n");
2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452
		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)
{
}
#endif

2453 2454
int proto_register(struct proto *prot, int alloc_slab)
{
L
Linus Torvalds 已提交
2455 2456
	if (alloc_slab) {
		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2457 2458
					SLAB_HWCACHE_ALIGN | prot->slab_flags,
					NULL);
L
Linus Torvalds 已提交
2459 2460

		if (prot->slab == NULL) {
J
Joe Perches 已提交
2461 2462
			pr_crit("%s: Can't create sock SLAB cache!\n",
				prot->name);
2463
			goto out;
L
Linus Torvalds 已提交
2464
		}
2465 2466

		if (prot->rsk_prot != NULL) {
2467
			prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2468
			if (prot->rsk_prot->slab_name == NULL)
2469 2470
				goto out_free_sock_slab;

2471
			prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2472
								 prot->rsk_prot->obj_size, 0,
2473
								 SLAB_HWCACHE_ALIGN, NULL);
2474 2475

			if (prot->rsk_prot->slab == NULL) {
J
Joe Perches 已提交
2476 2477
				pr_crit("%s: Can't create request sock SLAB cache!\n",
					prot->name);
2478 2479 2480
				goto out_free_request_sock_slab_name;
			}
		}
2481

2482
		if (prot->twsk_prot != NULL) {
2483
			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2484

2485
			if (prot->twsk_prot->twsk_slab_name == NULL)
2486 2487
				goto out_free_request_sock_slab;

2488
			prot->twsk_prot->twsk_slab =
2489
				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2490
						  prot->twsk_prot->twsk_obj_size,
2491 2492 2493
						  0,
						  SLAB_HWCACHE_ALIGN |
							prot->slab_flags,
2494
						  NULL);
2495
			if (prot->twsk_prot->twsk_slab == NULL)
2496 2497
				goto out_free_timewait_sock_slab_name;
		}
L
Linus Torvalds 已提交
2498 2499
	}

2500
	mutex_lock(&proto_list_mutex);
L
Linus Torvalds 已提交
2501
	list_add(&prot->node, &proto_list);
2502
	assign_proto_idx(prot);
2503
	mutex_unlock(&proto_list_mutex);
2504 2505
	return 0;

2506
out_free_timewait_sock_slab_name:
2507
	kfree(prot->twsk_prot->twsk_slab_name);
2508 2509 2510 2511 2512
out_free_request_sock_slab:
	if (prot->rsk_prot && prot->rsk_prot->slab) {
		kmem_cache_destroy(prot->rsk_prot->slab);
		prot->rsk_prot->slab = NULL;
	}
2513
out_free_request_sock_slab_name:
2514 2515
	if (prot->rsk_prot)
		kfree(prot->rsk_prot->slab_name);
2516 2517 2518
out_free_sock_slab:
	kmem_cache_destroy(prot->slab);
	prot->slab = NULL;
2519 2520
out:
	return -ENOBUFS;
L
Linus Torvalds 已提交
2521 2522 2523 2524 2525
}
EXPORT_SYMBOL(proto_register);

void proto_unregister(struct proto *prot)
{
2526
	mutex_lock(&proto_list_mutex);
2527
	release_proto_idx(prot);
2528
	list_del(&prot->node);
2529
	mutex_unlock(&proto_list_mutex);
L
Linus Torvalds 已提交
2530 2531 2532 2533 2534 2535

	if (prot->slab != NULL) {
		kmem_cache_destroy(prot->slab);
		prot->slab = NULL;
	}

2536 2537
	if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
		kmem_cache_destroy(prot->rsk_prot->slab);
2538
		kfree(prot->rsk_prot->slab_name);
2539 2540 2541
		prot->rsk_prot->slab = NULL;
	}

2542 2543
	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2544
		kfree(prot->twsk_prot->twsk_slab_name);
2545
		prot->twsk_prot->twsk_slab = NULL;
2546
	}
L
Linus Torvalds 已提交
2547 2548 2549 2550 2551
}
EXPORT_SYMBOL(proto_unregister);

#ifdef CONFIG_PROC_FS
static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2552
	__acquires(proto_list_mutex)
L
Linus Torvalds 已提交
2553
{
2554
	mutex_lock(&proto_list_mutex);
2555
	return seq_list_start_head(&proto_list, *pos);
L
Linus Torvalds 已提交
2556 2557 2558 2559
}

static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
2560
	return seq_list_next(v, &proto_list, pos);
L
Linus Torvalds 已提交
2561 2562 2563
}

static void proto_seq_stop(struct seq_file *seq, void *v)
2564
	__releases(proto_list_mutex)
L
Linus Torvalds 已提交
2565
{
2566
	mutex_unlock(&proto_list_mutex);
L
Linus Torvalds 已提交
2567 2568 2569 2570 2571 2572
}

static char proto_method_implemented(const void *method)
{
	return method == NULL ? 'n' : 'y';
}
2573 2574
static long sock_prot_memory_allocated(struct proto *proto)
{
2575
	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2576 2577 2578 2579 2580 2581 2582
}

static char *sock_prot_memory_pressure(struct proto *proto)
{
	return proto->memory_pressure != NULL ?
	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
}
L
Linus Torvalds 已提交
2583 2584 2585

static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
{
2586

E
Eric Dumazet 已提交
2587
	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
L
Linus Torvalds 已提交
2588 2589 2590
			"%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,
2591
		   sock_prot_inuse_get(seq_file_net(seq), proto),
2592 2593
		   sock_prot_memory_allocated(proto),
		   sock_prot_memory_pressure(proto),
L
Linus Torvalds 已提交
2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619
		   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)
{
2620
	if (v == &proto_list)
L
Linus Torvalds 已提交
2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631
		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
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		proto_seq_printf(seq, list_entry(v, struct proto, node));
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	return 0;
}

2636
static const struct seq_operations proto_seq_ops = {
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	.start  = proto_seq_start,
	.next   = proto_seq_next,
	.stop   = proto_seq_stop,
	.show   = proto_seq_show,
};

static int proto_seq_open(struct inode *inode, struct file *file)
{
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	return seq_open_net(inode, file, &proto_seq_ops,
			    sizeof(struct seq_net_private));
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}

2649
static const struct file_operations proto_seq_fops = {
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	.owner		= THIS_MODULE,
	.open		= proto_seq_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
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	.release	= seq_release_net,
};

static __net_init int proto_init_net(struct net *net)
{
	if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
		return -ENOMEM;

	return 0;
}

static __net_exit void proto_exit_net(struct net *net)
{
	proc_net_remove(net, "protocols");
}


static __net_initdata struct pernet_operations proto_net_ops = {
	.init = proto_init_net,
	.exit = proto_exit_net,
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};

static int __init proto_init(void)
{
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	return register_pernet_subsys(&proto_net_ops);
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}

subsys_initcall(proto_init);

#endif /* PROC_FS */