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WARNING: refcount bug in sock_wfree (2)

Status: closed as invalid on 2020/06/27 23:36
Reported-by: syzbot+c0ba5b9e742f049a2edf@syzkaller.appspotmail.com
Fix commit: io_uring: don't assign skb destructor unless fully set up
First crash: 1662d, last: 1483d
Cause bisection: introduced by (bisect log) :
commit 6c080ff07363389cb4092193eb333639f0392b8c
Author: Jens Axboe <axboe@kernel.dk>
Date: Thu Oct 3 14:11:03 2019 +0000

  io_uring: allow sparse fixed file sets

Crash: WARNING: refcount bug in sock_wfree (log)
Repro: C syz .config
  
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
WARNING: refcount bug in sock_wfree (2) 2 (3) 2019/10/14 15:01
▶ ▼ Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 WARNING: refcount bug in sock_wfree C done done 3 1496d 1617d 1/1 fixed on 2020/04/20 22:55
linux-4.19 WARNING: refcount bug in sock_wfree C done done 1 1496d 1616d 1/1 fixed on 2020/04/20 22:55
upstream WARNING: refcount bug in sock_wfree sctp syz error 24 1975d 2255d 0/26 closed as invalid on 2019/04/09 10:51

Sample crash report:
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 7215 at lib/refcount.c:28 refcount_warn_saturate+0x1d1/0x1e0 lib/refcount.c:28
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 7215 Comm: syz-executor053 Not tainted 5.6.0-rc7-syzkaller #0
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+0x188/0x20d lib/dump_stack.c:118
 panic+0x2e3/0x75c kernel/panic.c:221
 __warn.cold+0x2f/0x35 kernel/panic.c:582
 report_bug+0x27b/0x2f0 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 fixup_bug arch/x86/kernel/traps.c:169 [inline]
 do_error_trap+0x12b/0x220 arch/x86/kernel/traps.c:267
 do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:286
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:refcount_warn_saturate+0x1d1/0x1e0 lib/refcount.c:28
Code: e9 db fe ff ff 48 89 df e8 4c 63 1f fe e9 8a fe ff ff e8 f2 99 e2 fd 48 c7 c7 00 a9 51 88 c6 05 c6 a0 d1 06 01 e8 d7 aa b4 fd <0f> 0b e9 af fe ff ff 0f 1f 84 00 00 00 00 00 41 56 41 55 41 54 55
RSP: 0018:ffffc90001607698 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815c06c1 RDI: fffff520002c0ec5
RBP: 0000000000000003 R08: ffff888089d20140 R09: ffffed1015cc6659
R10: ffffed1015cc6658 R11: ffff8880ae6332c7 R12: 0000000000008100
R13: ffff8880a715ba04 R14: ffff88808fec3540 R15: ffff88808fec3580
 refcount_sub_and_test include/linux/refcount.h:261 [inline]
 sock_wfree+0x1e3/0x240 net/core/sock.c:1968
 sctp_wfree+0x372/0x960 net/sctp/socket.c:9111
 skb_release_head_state+0xe2/0x250 net/core/skbuff.c:651
 skb_release_all+0x11/0x60 net/core/skbuff.c:662
 __kfree_skb net/core/skbuff.c:678 [inline]
 consume_skb net/core/skbuff.c:837 [inline]
 consume_skb+0xf3/0x400 net/core/skbuff.c:831
 sctp_chunk_destroy net/sctp/sm_make_chunk.c:1454 [inline]
 sctp_chunk_put+0x1c0/0x2d0 net/sctp/sm_make_chunk.c:1481
 __sctp_outq_teardown+0x715/0xc60 net/sctp/outqueue.c:257
 sctp_association_free+0x212/0x7e0 net/sctp/associola.c:339
 sctp_cmd_delete_tcb net/sctp/sm_sideeffect.c:930 [inline]
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1318 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1185 [inline]
 sctp_do_sm+0x3911/0x4ed0 net/sctp/sm_sideeffect.c:1156
 sctp_primitive_ABORT+0x9b/0xc0 net/sctp/primitive.c:104
 sctp_close+0x22e/0x8a0 net/sctp/socket.c:1512
 inet_release+0xe4/0x1f0 net/ipv4/af_inet.c:427
 __sock_release+0xcd/0x280 net/socket.c:605
 sock_close+0x18/0x20 net/socket.c:1283
 __fput+0x2da/0x850 fs/file_table.c:280
 task_work_run+0x13f/0x1b0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xb34/0x2dd0 kernel/exit.c:801
 do_group_exit+0x125/0x340 kernel/exit.c:899
 __do_sys_exit_group kernel/exit.c:910 [inline]
 __se_sys_exit_group kernel/exit.c:908 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:908
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x43ef98
Code: Bad RIP value.
RSP: 002b:00007ffc04c40db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ef98
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00000000004be7a8 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 000000002059aff8 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d01a0 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (606):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/03/27 21:49 upstream 527630fbf4f1 831e9a81 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2020/03/26 01:47 upstream e2cf67f6689a 41f049cc .config console log report syz C ci-upstream-kasan-gce-root
2020/03/12 23:39 upstream e6e6ec48dd0f d850e9d0 .config console log report syz C ci-upstream-kasan-gce
2019/12/01 06:10 upstream 32ef9553635a a76bf83f .config console log report syz C ci-upstream-kasan-gce-selinux-root
2019/12/01 05:19 upstream 32ef9553635a a76bf83f .config console log report syz C ci-upstream-kasan-gce-smack-root
2019/11/30 16:13 upstream 81b6b96475ac 3a75be00 .config console log report syz C ci-upstream-kasan-gce-root
2019/11/30 08:29 upstream 81b6b96475ac 3a75be00 .config console log report syz C ci-upstream-kasan-gce
2019/11/22 16:40 upstream 81429eb8d9ca 598ca6c8 .config console log report syz C ci-upstream-kasan-gce-root
2019/11/22 16:38 upstream 81429eb8d9ca 598ca6c8 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2019/11/22 10:47 upstream 81429eb8d9ca 8098ea0f .config console log report syz C ci-upstream-kasan-gce-smack-root
2019/11/22 07:53 upstream 81429eb8d9ca 8098ea0f .config console log report syz C ci-upstream-kasan-gce
2020/03/13 06:41 upstream 3cc6e2c599cd d850e9d0 .config console log report syz C ci-upstream-kasan-gce-386
2019/11/30 19:50 upstream 81b6b96475ac 3a75be00 .config console log report syz C ci-upstream-kasan-gce-386
2019/11/22 09:39 upstream 81429eb8d9ca 8098ea0f .config console log report syz C ci-upstream-kasan-gce-386
2020/04/03 20:36 linux-next 770fbb32d34e 5ed396e6 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2019/12/14 16:38 linux-next 32b8acf85223 eef6e580 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2019/12/07 04:20 linux-next 838333c80c4f 85f26751 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2019/10/08 23:46 linux-next 442630f691a1 b1ebbfef .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2020/03/29 01:05 upstream 906c40438bb6 05736b29 .config console log report ci-upstream-kasan-gce-selinux-root
2020/03/27 03:07 upstream 9420e8ade435 6d25c5a0 .config console log report ci-upstream-kasan-gce-root
2020/03/25 16:39 upstream 76ccd234269b 41f049cc .config console log report ci-upstream-kasan-gce-root
2020/03/25 13:20 upstream 76ccd234269b 41f049cc .config console log report ci-upstream-kasan-gce
2020/03/23 01:38 upstream 67d584e33e54 78267cec .config console log report ci-upstream-kasan-gce-root
2020/03/22 12:52 upstream b74b991fb8b9 78267cec .config console log report ci-upstream-kasan-gce
2020/03/21 14:12 upstream 5ad0ec0b8652 4288d95e .config console log report ci-upstream-kasan-gce-root
2020/03/21 06:06 upstream 5ad0ec0b8652 2c31c529 .config console log report ci-upstream-kasan-gce
2020/03/20 15:04 upstream 6c90b86a745a 2c31c529 .config console log report ci-upstream-kasan-gce
2020/03/19 20:23 upstream cd607737f3b8 2c31c529 .config console log report ci-upstream-kasan-gce-root
2020/03/19 18:18 upstream cd607737f3b8 2c31c529 .config console log report ci-upstream-kasan-gce
2020/03/18 18:08 upstream 5076190daded 0a96a13c .config console log report ci-upstream-kasan-gce-selinux-root
2020/03/18 15:32 upstream ac309e7744be 97bc55ce .config console log report ci-upstream-kasan-gce
2020/03/09 22:46 upstream 2c523b344dfa 35f53e45 .config console log report ci-upstream-kasan-gce-selinux-root
2020/03/09 21:14 upstream 2c523b344dfa 35f53e45 .config console log report ci-upstream-kasan-gce
2020/03/03 18:25 upstream 63623fd44972 c88c7b75 .config console log report ci-upstream-kasan-gce-smack-root
2020/03/02 07:00 upstream 63623fd44972 c88c7b75 .config console log report ci-upstream-kasan-gce-smack-root
2020/03/01 09:34 upstream 63623fd44972 c88c7b75 .config console log report ci-upstream-kasan-gce-root
2020/02/29 11:16 upstream f8788d86ab28 59b57593 .config console log report ci-upstream-kasan-gce-selinux-root
2020/02/27 11:47 upstream f8788d86ab28 59b57593 .config console log report ci-upstream-kasan-gce-root
2020/02/25 17:44 upstream f8788d86ab28 59b57593 .config console log report ci-upstream-kasan-gce-selinux-root
2020/02/24 04:52 upstream d2eee25858f2 d801cb02 .config console log report ci-upstream-kasan-gce
2020/02/23 04:01 upstream 54dedb5b571d 2c36e7a7 .config console log report ci-upstream-kasan-gce-smack-root
2020/02/21 06:28 upstream ca7e1fd1026c bd2a74a3 .config console log report ci-upstream-kasan-gce-smack-root
2020/02/20 10:01 upstream ca7e1fd1026c 81230308 .config console log report ci-upstream-kasan-gce
2020/02/20 09:46 upstream ca7e1fd1026c 81230308 .config console log report ci-upstream-kasan-gce-selinux-root
2020/02/18 04:01 upstream 11a48a5a18c6 1ce142dc .config console log report ci-upstream-kasan-gce-root
2020/02/18 03:59 upstream 11a48a5a18c6 1ce142dc .config console log report ci-upstream-kasan-gce-selinux-root
2020/02/17 01:11 upstream 11a48a5a18c6 1f448cd6 .config console log report ci-upstream-kasan-gce-root
2020/02/15 08:53 upstream 2019fc96af22 5d7b90f1 .config console log report ci-upstream-kasan-gce-smack-root
2020/02/13 07:11 upstream f2850dd5ee01 84f4fc8a .config console log report ci-upstream-kasan-gce-smack-root
2020/02/12 04:08 upstream 359c92c02bfa a75b198c .config console log report ci-upstream-kasan-gce-smack-root
2020/02/10 11:29 upstream bb6d3fb354c5 35f5e45e .config console log report ci-upstream-kasan-gce-selinux-root
2020/02/09 18:21 upstream fdfa3a6778b1 6ece2ea5 .config console log report ci-upstream-kasan-gce-selinux-root
2020/01/30 11:32 upstream 6ba3d7066c71 5ed23f9a .config console log report ci-qemu-upstream
2020/03/27 03:09 upstream 9420e8ade435 6d25c5a0 .config console log report ci-upstream-kasan-gce-386
2020/03/25 15:20 upstream 76ccd234269b 41f049cc .config console log report ci-upstream-kasan-gce-386
2020/03/21 12:58 upstream 5ad0ec0b8652 4288d95e .config console log report ci-upstream-kasan-gce-386
2020/03/19 14:57 upstream 5076190daded 2c31c529 .config console log report ci-upstream-kasan-gce-386
2020/03/01 10:07 upstream 63623fd44972 c88c7b75 .config console log report ci-upstream-kasan-gce-386
2020/02/16 02:30 upstream 829e69446995 5d7b90f1 .config console log report ci-upstream-kasan-gce-386
2020/02/15 21:21 upstream 829e69446995 5d7b90f1 .config console log report ci-upstream-kasan-gce-386
2020/03/29 03:02 linux-next 770fbb32d34e 05736b29 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/03/22 11:45 linux-next 770fbb32d34e 78267cec .config console log report ci-upstream-linux-next-kasan-gce-root
2020/03/21 16:00 linux-next 770fbb32d34e 4288d95e .config console log report ci-upstream-linux-next-kasan-gce-root
2020/03/19 15:08 linux-next 770fbb32d34e 2c31c529 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/02/27 11:32 linux-next bdc5461b23ca 59b57593 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/02/14 22:36 linux-next 9f01828e9e16 5d7b90f1 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/02/12 05:51 linux-next 129759899765 a75b198c .config console log report ci-upstream-linux-next-kasan-gce-root
2019/10/08 12:28 linux-next 442630f691a1 28ac6e64 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.