WARNING: refcount bug in smc_tcp_listen_work

Status: fixed on 2018/08/07 13:43
Subsystems: net s390
[Documentation on labels]
Fix commit: e1bbdd570474 net/smc: reduce sock_put() for fallback sockets
First crash: 2006d, last: 2006d
Discussions (2)
Title Replies (including bot) Last reply
[PATCH net 1/1] net/smc: reduce sock_put() for fallback sockets 2 (2) 2018/07/07 11:25
WARNING: refcount bug in smc_tcp_listen_work 0 (1) 2018/06/06 13:32

Sample crash report:
A link change request failed with some changes committed already. Interface bridge0 may have been left with an inconsistent configuration, please check.
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 23870 at lib/refcount.c:187 refcount_sub_and_test+0x2d3/0x330 lib/refcount.c:187
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 23870 Comm: kworker/0:4 Not tainted 4.17.0-rc7+ #79
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events smc_tcp_listen_work
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
 panic+0x22f/0x4de kernel/panic.c:184
 __warn.cold.8+0x163/0x1b3 kernel/panic.c:536
 report_bug+0x252/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x1de/0x490 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992
RIP: 0010:refcount_sub_and_test+0x2d3/0x330 lib/refcount.c:187
RSP: 0018:ffff880194aaf4f8 EFLAGS: 00010286
RAX: 0000000000000026 RBX: 0000000000000000 RCX: ffffffff8160b8ad
RDX: 0000000000000000 RSI: ffffffff81610561 RDI: ffff880194aaf058
RBP: ffff880194aaf5e0 R08: ffff88014148e500 R09: 0000000000000006
R10: ffff88014148e500 R11: 0000000000000000 R12: 00000000ffffffff
R13: ffff880194aaf5b8 R14: 0000000000000001 R15: ffff880194aaf728
 refcount_dec_and_test+0x1a/0x20 lib/refcount.c:212
 sock_put include/net/sock.h:1668 [inline]
 smc_tcp_listen_work+0xb94/0xec0 net/smc/af_smc.c:1073
 process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145
 worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279
 kthread+0x345/0x410 kernel/kthread.c:240
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/06/06 09:20 net-next-old 75d4e704fa8d 41f9540d .config console log report ci-upstream-net-kasan-gce
* Struck through repros no longer work on HEAD.