syzbot


BUG: corrupted list in p9_conn_cancel

Status: fixed on 2019/11/11 16:48
Subsystems: v9fs
[Documentation on labels]
Reported-by: syzbot+ad0832746849421bba05@syzkaller.appspotmail.com
Fix commit: 9f476d7c540c net/9p/trans_fd.c: fix race by holding the lock
First crash: 2106d, last: 2005d
Fix bisection: fixed by (bisect log) :
commit 9f476d7c540cb57556d3cc7e78704e6cd5100f5f
Author: Tomas Bortoli <tomasbortoli@gmail.com>
Date: Mon Jul 23 18:42:53 2018 +0000

  net/9p/trans_fd.c: fix race by holding the lock

  
Discussions (3)
Title Replies (including bot) Last reply
BUG: corrupted list in p9_conn_cancel 0 (2) 2019/11/07 13:42
Reminder: 18 open syzbot bugs in "fs/9p" subsystem 1 (1) 2019/07/24 01:46
Reminder: 18 open syzbot bugs in "fs/9p" subsystem 1 (1) 2019/07/02 06:29
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: corrupted list in p9_conn_cancel (3) v9fs 1 241d 237d 0/26 auto-obsoleted due to no activity on 2023/11/14 18:11
upstream BUG: corrupted list in p9_conn_cancel (2) v9fs 1 431d 427d 0/26 auto-obsoleted due to no activity on 2023/05/08 23:23
linux-4.14 BUG: corrupted list in p9_conn_cancel syz error 5 1407d 1657d 0/1 upstream: reported syz repro on 2019/10/01 03:22

Sample crash report:
list_del corruption. next->prev should be ffff88012ed59368, but was ffff8801cd53f3b0
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:56!
invalid opcode: 0000 [#1] SMP KASAN
CPU: 1 PID: 2133 Comm: kworker/1:2 Not tainted 4.18.0-rc4+ #142
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events p9_poll_workfn
RIP: 0010:__list_del_entry_valid.cold.1+0x37/0x58 lib/list_debug.c:54
Code: e8 4a 6e 02 fe 0f 0b 4c 89 ea 48 89 de 48 c7 c7 c0 65 1a 88 e8 36 6e 02 fe 0f 0b 48 89 de 48 c7 c7 e0 66 1a 88 e8 25 6e 02 fe <0f> 0b 48 89 de 48 c7 c7 80 66 1a 88 e8 14 6e 02 fe 0f 0b 90 90 90 
RSP: 0018:ffff8801cd53f318 EFLAGS: 00010282
RAX: 0000000000000054 RBX: ffff88012ed59368 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81631821 RDI: 0000000000000001
RBP: ffff8801cd53f330 R08: ffff8801cd54e680 R09: ffffed003b5e4fc0
R10: ffffed003b5e4fc0 R11: ffff8801daf27e07 R12: ffff8801cd53f3b0
R13: ffff8801cd53f3b0 R14: ffff8801cd53f388 R15: 1ffff10039aa7e9e
FS:  0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000000 CR3: 0000000008e6a000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __list_del_entry include/linux/list.h:117 [inline]
 list_del include/linux/list.h:125 [inline]
 p9_conn_cancel+0x8d6/0xd30 net/9p/trans_fd.c:224
 p9_poll_mux net/9p/trans_fd.c:620 [inline]
 p9_poll_workfn+0x4b2/0x6d0 net/9p/trans_fd.c:1107
 process_one_work+0xc73/0x1ba0 kernel/workqueue.c:2153
 worker_thread+0x189/0x13c0 kernel/workqueue.c:2296
 kthread+0x345/0x410 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
Modules linked in:
Dumping ftrace buffer:
   (ftrace buffer empty)
---[ end trace 1586ea80a4eed1d0 ]---
RIP: 0010:__list_del_entry_valid.cold.1+0x37/0x58 lib/list_debug.c:54
Code: e8 4a 6e 02 fe 0f 0b 4c 89 ea 48 89 de 48 c7 c7 c0 65 1a 88 e8 36 6e 02 fe 0f 0b 48 89 de 48 c7 c7 e0 66 1a 88 e8 25 6e 02 fe <0f> 0b 48 89 de 48 c7 c7 80 66 1a 88 e8 14 6e 02 fe 0f 0b 90 90 90 
RSP: 0018:ffff8801cd53f318 EFLAGS: 00010282
RAX: 0000000000000054 RBX: ffff88012ed59368 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81631821 RDI: 0000000000000001
RBP: ffff8801cd53f330 R08: ffff8801cd54e680 R09: ffffed003b5e4fc0
R10: ffffed003b5e4fc0 R11: ffff8801daf27e07 R12: ffff8801cd53f3b0
R13: ffff8801cd53f3b0 R14: ffff8801cd53f388 R15: 1ffff10039aa7e9e
FS:  0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000000 CR3: 0000000008e6a000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (18):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/07/11 23:56 upstream c25c74b7476e 2e0e3130 .config console log report syz C ci-upstream-kasan-gce
2018/07/11 15:16 upstream 1e09177acae3 2e0e3130 .config console log report syz C ci-upstream-kasan-gce
2018/07/10 22:45 upstream 30c2c32d7f70 2e0e3130 .config console log report syz C ci-upstream-kasan-gce
2018/07/10 18:10 upstream 092150a25cb7 9fa03fa5 .config console log report syz C ci-upstream-kasan-gce
2018/07/10 14:45 upstream 092150a25cb7 9fa03fa5 .config console log report syz C ci-upstream-kasan-gce
2018/07/10 04:52 upstream 092150a25cb7 f25e5770 .config console log report syz C ci-upstream-kasan-gce
2018/07/10 21:42 upstream 30c2c32d7f70 2e0e3130 .config console log report syz C ci-upstream-kasan-gce-386
2018/07/10 06:44 upstream 092150a25cb7 f25e5770 .config console log report syz C ci-upstream-kasan-gce-386
2018/07/10 05:10 upstream 092150a25cb7 f25e5770 .config console log report syz C ci-upstream-kasan-gce-386
2018/07/09 10:53 upstream ca04b3cca11a f25e5770 .config console log report syz C ci-upstream-kasan-gce-386
2018/07/13 18:03 linux-next 483d835c8189 92a49505 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2018/07/10 17:01 upstream 092150a25cb7 9fa03fa5 .config console log report syz ci-upstream-kasan-gce-386
2018/10/18 04:50 upstream c343db455eb3 b2695b95 .config console log report ci-upstream-kasan-gce-selinux-root
2018/08/12 17:51 upstream ec0c96714e7d 7a88b141 .config console log report ci-upstream-kasan-gce-root
2018/08/04 05:47 upstream 0b5b1f9a78b5 df7f6947 .config console log report ci-upstream-kasan-gce-root
2018/07/10 12:35 upstream 092150a25cb7 9fa03fa5 .config console log report ci-upstream-kasan-gce
2018/07/10 05:35 upstream 092150a25cb7 f25e5770 .config console log report ci-upstream-kasan-gce-root
2018/07/10 12:38 upstream 092150a25cb7 9fa03fa5 .config console log report ci-upstream-kasan-gce-386
* Struck through repros no longer work on HEAD.