| From foo@baz Sun Feb 10 12:47:17 CET 2019 |
| From: Eric Dumazet <edumazet@google.com> |
| Date: Mon, 4 Feb 2019 08:36:06 -0800 |
| Subject: rxrpc: bad unlock balance in rxrpc_recvmsg |
| |
| From: Eric Dumazet <edumazet@google.com> |
| |
| [ Upstream commit 6dce3c20ac429e7a651d728e375853370c796e8d ] |
| |
| When either "goto wait_interrupted;" or "goto wait_error;" |
| paths are taken, socket lock has already been released. |
| |
| This patch fixes following syzbot splat : |
| |
| WARNING: bad unlock balance detected! |
| 5.0.0-rc4+ #59 Not tainted |
| ------------------------------------- |
| syz-executor223/8256 is trying to release lock (sk_lock-AF_RXRPC) at: |
| [<ffffffff86651353>] rxrpc_recvmsg+0x6d3/0x3099 net/rxrpc/recvmsg.c:598 |
| but there are no more locks to release! |
| |
| other info that might help us debug this: |
| 1 lock held by syz-executor223/8256: |
| #0: 00000000fa9ed0f4 (slock-AF_RXRPC){+...}, at: spin_lock_bh include/linux/spinlock.h:334 [inline] |
| #0: 00000000fa9ed0f4 (slock-AF_RXRPC){+...}, at: release_sock+0x20/0x1c0 net/core/sock.c:2798 |
| |
| stack backtrace: |
| CPU: 1 PID: 8256 Comm: syz-executor223 Not tainted 5.0.0-rc4+ #59 |
| Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 |
| Call Trace: |
| __dump_stack lib/dump_stack.c:77 [inline] |
| dump_stack+0x172/0x1f0 lib/dump_stack.c:113 |
| print_unlock_imbalance_bug kernel/locking/lockdep.c:3391 [inline] |
| print_unlock_imbalance_bug.cold+0x114/0x123 kernel/locking/lockdep.c:3368 |
| __lock_release kernel/locking/lockdep.c:3601 [inline] |
| lock_release+0x67e/0xa00 kernel/locking/lockdep.c:3860 |
| sock_release_ownership include/net/sock.h:1471 [inline] |
| release_sock+0x183/0x1c0 net/core/sock.c:2808 |
| rxrpc_recvmsg+0x6d3/0x3099 net/rxrpc/recvmsg.c:598 |
| sock_recvmsg_nosec net/socket.c:794 [inline] |
| sock_recvmsg net/socket.c:801 [inline] |
| sock_recvmsg+0xd0/0x110 net/socket.c:797 |
| __sys_recvfrom+0x1ff/0x350 net/socket.c:1845 |
| __do_sys_recvfrom net/socket.c:1863 [inline] |
| __se_sys_recvfrom net/socket.c:1859 [inline] |
| __x64_sys_recvfrom+0xe1/0x1a0 net/socket.c:1859 |
| do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 |
| entry_SYSCALL_64_after_hwframe+0x49/0xbe |
| RIP: 0033:0x446379 |
| Code: e8 2c b3 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 2b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00 |
| RSP: 002b:00007fe5da89fd98 EFLAGS: 00000246 ORIG_RAX: 000000000000002d |
| RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 0000000000446379 |
| RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 |
| RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000 |
| R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c |
| R13: 0000000000000000 R14: 0000000000000000 R15: 20c49ba5e353f7cf |
| |
| Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code") |
| Signed-off-by: Eric Dumazet <edumazet@google.com> |
| Cc: David Howells <dhowells@redhat.com> |
| Reported-by: syzbot <syzkaller@googlegroups.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/rxrpc/recvmsg.c | 3 ++- |
| 1 file changed, 2 insertions(+), 1 deletion(-) |
| |
| --- a/net/rxrpc/recvmsg.c |
| +++ b/net/rxrpc/recvmsg.c |
| @@ -588,6 +588,7 @@ error_requeue_call: |
| } |
| error_no_call: |
| release_sock(&rx->sk); |
| +error_trace: |
| trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, 0, 0, 0, ret); |
| return ret; |
| |
| @@ -596,7 +597,7 @@ wait_interrupted: |
| wait_error: |
| finish_wait(sk_sleep(&rx->sk), &wait); |
| call = NULL; |
| - goto error_no_call; |
| + goto error_trace; |
| } |
| |
| /** |