From 1c23c2941712bb6ddce3715b7def5c74253732ad Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 4 Feb 2019 08:36:06 -0800 Subject: rxrpc: bad unlock balance in rxrpc_recvmsg [ 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: [] 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 Cc: David Howells Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/rxrpc/recvmsg.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c index 3e52b7fdc35d..72de69175476 100644 --- a/net/rxrpc/recvmsg.c +++ b/net/rxrpc/recvmsg.c @@ -552,6 +552,7 @@ error: rxrpc_put_call(call, rxrpc_call_put); error_no_call: release_sock(&rx->sk); +error_trace: trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, 0, 0, 0, ret); return ret; @@ -560,7 +561,7 @@ wait_interrupted: wait_error: finish_wait(sk_sleep(&rx->sk), &wait); call = NULL; - goto error_no_call; + goto error_trace; } /** -- cgit v1.2.3