syzbot


WARNING: bad unlock balance in rxrpc_recvmsg

Status: fixed on 2019/03/06 07:43
Subsystems: afs net
[Documentation on labels]
Fix commit: 6dce3c20ac42 rxrpc: bad unlock balance in rxrpc_recvmsg
First crash: 1992d, last: 1988d

Sample crash report:
=====================================
WARNING: bad unlock balance detected!
5.0.0-rc4+ #59 Not tainted
-------------------------------------
syz-executor942/7854 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-executor942/7854:
 #0: 00000000bf19f417 (slock-AF_RXRPC){+...}, at: spin_lock_bh include/linux/spinlock.h:334 [inline]
 #0: 00000000bf19f417 (slock-AF_RXRPC){+...}, at: release_sock+0x20/0x1c0 net/core/sock.c:2798

stack backtrace:
CPU: 0 PID: 7854 Comm: syz-executor942 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: 0033:0x446399
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:00007f02d1ec5d98 EFLAGS: 00000246 ORIG_RAX: 000000000000002d
RAX: ffffffffffffffda RBX: 00000000006dbc38 RCX: 0000000000446399
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00000000006dbc30 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 00000000006dbc3c
R13: 0000000000000000 R14: 0000000000000000 R15: 20c49ba5e353f7cf

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/02/04 06:13 upstream 24b888d8d598 c198d5dd .config console log report syz C ci-upstream-kasan-gce-selinux-root
2019/02/04 05:40 upstream 24b888d8d598 c198d5dd .config console log report syz C ci-upstream-kasan-gce-root
2019/02/04 05:34 upstream 24b888d8d598 c198d5dd .config console log report syz C ci-upstream-kasan-gce-smack-root
2019/02/04 05:46 upstream 24b888d8d598 c198d5dd .config console log report syz C ci-upstream-kasan-gce-386
2019/02/04 14:37 upstream 8834f5600cf3 d672172c .config console log report syz ci-upstream-kasan-gce
2019/02/04 05:14 linux-next dc4c89997735 c198d5dd .config console log report syz ci-upstream-linux-next-kasan-gce-root
2019/02/08 07:40 net-next-old fc4aa1ca1628 aa4feb03 .config console log report ci-upstream-net-kasan-gce
2019/02/05 20:43 net-next-old 5468e82f7034 d672172c .config console log report ci-upstream-net-kasan-gce
2019/02/04 04:54 linux-next dc4c89997735 c198d5dd .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.