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| author | Xin Long <lucien.xin@gmail.com> | 2017-06-10 08:56:56 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-06-10 22:22:25 +0200 |
| commit | 6dfe4b97e08ec3d1a593fdaca099f0ef0a3a19e6 (patch) | |
| tree | 410f8487b0c3467dff585d3f3defa9a4fba5048c /net/sctp | |
| parent | net/packet: remove unneeded declaraion of tpacket_snd(). (diff) | |
| download | linux-6dfe4b97e08ec3d1a593fdaca099f0ef0a3a19e6.tar.xz linux-6dfe4b97e08ec3d1a593fdaca099f0ef0a3a19e6.zip | |
sctp: fix recursive locking warning in sctp_do_peeloff
Dmitry got the following recursive locking report while running syzkaller
fuzzer, the Call Trace:
__dump_stack lib/dump_stack.c:16 [inline]
dump_stack+0x2ee/0x3ef lib/dump_stack.c:52
print_deadlock_bug kernel/locking/lockdep.c:1729 [inline]
check_deadlock kernel/locking/lockdep.c:1773 [inline]
validate_chain kernel/locking/lockdep.c:2251 [inline]
__lock_acquire+0xef2/0x3430 kernel/locking/lockdep.c:3340
lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755
lock_sock_nested+0xcb/0x120 net/core/sock.c:2536
lock_sock include/net/sock.h:1460 [inline]
sctp_close+0xcd/0x9d0 net/sctp/socket.c:1497
inet_release+0xed/0x1c0 net/ipv4/af_inet.c:425
inet6_release+0x50/0x70 net/ipv6/af_inet6.c:432
sock_release+0x8d/0x1e0 net/socket.c:597
__sock_create+0x38b/0x870 net/socket.c:1226
sock_create+0x7f/0xa0 net/socket.c:1237
sctp_do_peeloff+0x1a2/0x440 net/sctp/socket.c:4879
sctp_getsockopt_peeloff net/sctp/socket.c:4914 [inline]
sctp_getsockopt+0x111a/0x67e0 net/sctp/socket.c:6628
sock_common_getsockopt+0x95/0xd0 net/core/sock.c:2690
SYSC_getsockopt net/socket.c:1817 [inline]
SyS_getsockopt+0x240/0x380 net/socket.c:1799
entry_SYSCALL_64_fastpath+0x1f/0xc2
This warning is caused by the lock held by sctp_getsockopt() is on one
socket, while the other lock that sctp_close() is getting later is on
the newly created (which failed) socket during peeloff operation.
This patch is to avoid this warning by use lock_sock with subclass
SINGLE_DEPTH_NESTING as Wang Cong and Marcelo's suggestion.
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Suggested-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/sctp')
| -rw-r--r-- | net/sctp/socket.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 5f58dd03e3ac..32d5495e793c 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -1494,7 +1494,7 @@ static void sctp_close(struct sock *sk, long timeout) pr_debug("%s: sk:%p, timeout:%ld\n", __func__, sk, timeout); - lock_sock(sk); + lock_sock_nested(sk, SINGLE_DEPTH_NESTING); sk->sk_shutdown = SHUTDOWN_MASK; sk->sk_state = SCTP_SS_CLOSING; @@ -1544,7 +1544,7 @@ static void sctp_close(struct sock *sk, long timeout) * held and that should be grabbed before socket lock. */ spin_lock_bh(&net->sctp.addr_wq_lock); - bh_lock_sock(sk); + bh_lock_sock_nested(sk); /* Hold the sock, since sk_common_release() will put sock_put() * and we have just a little more cleanup. |