linux-stable.git/net/core/sock.c, branch linux-4.19.y

ipv6: Fix data races around sk->sk_prot.

2024-07-05T07:00:35+00:00

commit 364f997b5cfe1db0d63a390fe7c801fa2b3115f6 upstream.

Commit 086d49058cd8 ("ipv6: annotate some data-races around sk->sk_prot")
fixed some data-races around sk->sk_prot but it was not enough.

Some functions in inet6_(stream|dgram)_ops still access sk->sk_prot
without lock_sock() or rtnl_lock(), so they need READ_ONCE() to avoid
load tearing.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima 
Signed-off-by: Jakub Kicinski 
Signed-off-by: Kazunori Kobayashi 
Signed-off-by: Greg Kroah-Hartman

net: mark racy access on sk->sk_rcvbuf

2024-05-17T09:42:39+00:00

[ Upstream commit c2deb2e971f5d9aca941ef13ee05566979e337a4 ]

sk->sk_rcvbuf in __sock_queue_rcv_skb() and __sk_receive_skb() can be
changed by other threads. Mark this as benign using READ_ONCE().

This patch is aimed at reducing the number of benign races reported by
KCSAN in order to focus future debugging effort on harmful races.

Signed-off-by: linke li 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

mptcp: add sk_stop_timer_sync helper

2024-04-13T10:50:12+00:00

[ Upstream commit 08b81d873126b413cda511b1ea1cbb0e99938bbd ]

This patch added a new helper sk_stop_timer_sync, it deactivates a timer
like sk_stop_timer, but waits for the handler to finish.

Acked-by: Paolo Abeni 
Signed-off-by: Geliang Tang 
Reviewed-by: Mat Martineau 
Signed-off-by: David S. Miller 
Stable-dep-of: 151c9c724d05 ("tcp: properly terminate timers for kernel sockets")
Signed-off-by: Sasha Levin

net: annotate data-races around sk->sk_dst_pending_confirm

2023-11-28T16:46:31+00:00

[ Upstream commit eb44ad4e635132754bfbcb18103f1dcb7058aedd ]

This field can be read or written without socket lock being held.

Add annotations to avoid load-store tearing.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

af_unix: Fix data race around sk->sk_err.

2023-09-23T08:48:13+00:00

[ Upstream commit b192812905e4b134f7b7994b079eb647e9d2d37e ]

As with sk->sk_shutdown shown in the previous patch, sk->sk_err can be
read locklessly by unix_dgram_sendmsg().

Let's use READ_ONCE() for sk_err as well.

Note that the writer side is marked by commit cc04410af7de ("af_unix:
annotate lockless accesses to sk->sk_err").

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

af_unix: Fix data-races around sk->sk_shutdown.

2023-09-23T08:48:13+00:00

[ Upstream commit afe8764f76346ba838d4f162883e23d2fcfaa90e ]

sk->sk_shutdown is changed under unix_state_lock(sk), but
unix_dgram_sendmsg() calls two functions to read sk_shutdown locklessly.

  sock_alloc_send_pskb
  `- sock_wait_for_wmem

Let's use READ_ONCE() there.

Note that the writer side was marked by commit e1d09c2c2f57 ("af_unix:
Fix data races around sk->sk_shutdown.").

BUG: KCSAN: data-race in sock_alloc_send_pskb / unix_release_sock

write (marked) to 0xffff8880069af12c of 1 bytes by task 1 on cpu 1:
 unix_release_sock+0x75c/0x910 net/unix/af_unix.c:631
 unix_release+0x59/0x80 net/unix/af_unix.c:1053
 __sock_release+0x7d/0x170 net/socket.c:654
 sock_close+0x19/0x30 net/socket.c:1386
 __fput+0x2a3/0x680 fs/file_table.c:384
 ____fput+0x15/0x20 fs/file_table.c:412
 task_work_run+0x116/0x1a0 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x174/0x180 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:297
 do_syscall_64+0x4b/0x90 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x6e/0xd8

read to 0xffff8880069af12c of 1 bytes by task 28650 on cpu 0:
 sock_alloc_send_pskb+0xd2/0x620 net/core/sock.c:2767
 unix_dgram_sendmsg+0x2f8/0x14f0 net/unix/af_unix.c:1944
 unix_seqpacket_sendmsg net/unix/af_unix.c:2308 [inline]
 unix_seqpacket_sendmsg+0xba/0x130 net/unix/af_unix.c:2292
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg+0x148/0x160 net/socket.c:748
 ____sys_sendmsg+0x4e4/0x610 net/socket.c:2494
 ___sys_sendmsg+0xc6/0x140 net/socket.c:2548
 __sys_sendmsg+0x94/0x140 net/socket.c:2577
 __do_sys_sendmsg net/socket.c:2586 [inline]
 __se_sys_sendmsg net/socket.c:2584 [inline]
 __x64_sys_sendmsg+0x45/0x50 net/socket.c:2584
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x6e/0xd8

value changed: 0x00 -> 0x03

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 28650 Comm: systemd-coredum Not tainted 6.4.0-11989-g6843306689af #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzkaller 
Signed-off-by: Kuniyuki Iwashima 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: read sk->sk_family once in sk_mc_loop()

2023-09-23T08:48:13+00:00

[ Upstream commit a3e0fdf71bbe031de845e8e08ed7fba49f9c702c ]

syzbot is playing with IPV6_ADDRFORM quite a lot these days,
and managed to hit the WARN_ON_ONCE(1) in sk_mc_loop()

We have many more similar issues to fix.

WARNING: CPU: 1 PID: 1593 at net/core/sock.c:782 sk_mc_loop+0x165/0x260
Modules linked in:
CPU: 1 PID: 1593 Comm: kworker/1:3 Not tainted 6.1.40-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Workqueue: events_power_efficient gc_worker
RIP: 0010:sk_mc_loop+0x165/0x260 net/core/sock.c:782
Code: 34 1b fd 49 81 c7 18 05 00 00 4c 89 f8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ff e8 25 36 6d fd 4d 8b 37 eb 13 e8 db 33 1b fd <0f> 0b b3 01 eb 34 e8 d0 33 1b fd 45 31 f6 49 83 c6 38 4c 89 f0 48
RSP: 0018:ffffc90000388530 EFLAGS: 00010246
RAX: ffffffff846d9b55 RBX: 0000000000000011 RCX: ffff88814f884980
RDX: 0000000000000102 RSI: ffffffff87ae5160 RDI: 0000000000000011
RBP: ffffc90000388550 R08: 0000000000000003 R09: ffffffff846d9a65
R10: 0000000000000002 R11: ffff88814f884980 R12: dffffc0000000000
R13: ffff88810dbee000 R14: 0000000000000010 R15: ffff888150084000
FS: 0000000000000000(0000) GS:ffff8881f6b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000180 CR3: 000000014ee5b000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:

[] ip6_finish_output2+0x33f/0x1ae0 net/ipv6/ip6_output.c:83
[] __ip6_finish_output net/ipv6/ip6_output.c:200 [inline]
[] ip6_finish_output+0x6c6/0xb10 net/ipv6/ip6_output.c:211
[] NF_HOOK_COND include/linux/netfilter.h:298 [inline]
[] ip6_output+0x2bc/0x3d0 net/ipv6/ip6_output.c:232
[] dst_output include/net/dst.h:444 [inline]
[] ip6_local_out+0x10f/0x140 net/ipv6/output_core.c:161
[] ipvlan_process_v6_outbound drivers/net/ipvlan/ipvlan_core.c:483 [inline]
[] ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:529 [inline]
[] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline]
[] ipvlan_queue_xmit+0x1174/0x1be0 drivers/net/ipvlan/ipvlan_core.c:677
[] ipvlan_start_xmit+0x49/0x100 drivers/net/ipvlan/ipvlan_main.c:229
[] netdev_start_xmit include/linux/netdevice.h:4925 [inline]
[] xmit_one net/core/dev.c:3644 [inline]
[] dev_hard_start_xmit+0x320/0x980 net/core/dev.c:3660
[] sch_direct_xmit+0x2a0/0x9c0 net/sched/sch_generic.c:342
[] qdisc_restart net/sched/sch_generic.c:407 [inline]
[] __qdisc_run+0xb13/0x1e70 net/sched/sch_generic.c:415
[] qdisc_run+0xd6/0x260 include/net/pkt_sched.h:125
[] net_tx_action+0x7ac/0x940 net/core/dev.c:5247
[] __do_softirq+0x2bd/0x9bd kernel/softirq.c:599
[] invoke_softirq kernel/softirq.c:430 [inline]
[] __irq_exit_rcu+0xc8/0x170 kernel/softirq.c:683
[] irq_exit_rcu+0x9/0x20 kernel/softirq.c:695

Fixes: 7ad6848c7e81 ("ip: fix mc_loop checks for tunnels with multicast outer addresses")
Reported-by: syzbot 
Signed-off-by: Eric Dumazet 
Reviewed-by: Kuniyuki Iwashima 
Link: https://lore.kernel.org/r/20230830101244.1146934-1-edumazet@google.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

sock: Fix misuse of sk_under_memory_pressure()

2023-08-30T14:31:49+00:00

[ Upstream commit 2d0c88e84e483982067a82073f6125490ddf3614 ]

The status of global socket memory pressure is updated when:

  a) __sk_mem_raise_allocated():

	enter: sk_memory_allocated(sk) >  sysctl_mem[1]
	leave: sk_memory_allocated(sk) <= sysctl_mem[0]

  b) __sk_mem_reduce_allocated():

	leave: sk_under_memory_pressure(sk) &&
		sk_memory_allocated(sk) < sysctl_mem[0]

So the conditions of leaving global pressure are inconstant, which
may lead to the situation that one pressured net-memcg prevents the
global pressure from being cleared when there is indeed no global
pressure, thus the global constrains are still in effect unexpectedly
on the other sockets.

This patch fixes this by ignoring the net-memcg's pressure when
deciding whether should leave global memory pressure.

Fixes: e1aab161e013 ("socket: initial cgroup code.")
Signed-off-by: Abel Wu 
Acked-by: Shakeel Butt 
Link: https://lore.kernel.org/r/20230816091226.1542-1-wuyun.abel@bytedance.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

net: add missing data-race annotation for sk_ll_usec

2023-08-11T09:45:37+00:00

[ Upstream commit e5f0d2dd3c2faa671711dac6d3ff3cef307bcfe3 ]

In a prior commit I forgot that sk_getsockopt() reads
sk->sk_ll_usec without holding a lock.

Fixes: 0dbffbb5335a ("net: annotate data race around sk_ll_usec")
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: add missing data-race annotations around sk->sk_peek_off

2023-08-11T09:45:37+00:00

[ Upstream commit 11695c6e966b0ec7ed1d16777d294cef865a5c91 ]

sk_getsockopt() runs locklessly, thus we need to annotate the read
of sk->sk_peek_off.

While we are at it, add corresponding annotations to sk_set_peek_off()
and unix_set_peek_off().

Fixes: b9bb53f3836f ("sock: convert sk_peek_offset functions to WRITE_ONCE")
Signed-off-by: Eric Dumazet 
Cc: Willem de Bruijn 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin