syzbot


BUG: unable to handle kernel NULL pointer dereference in call_rcu

Status: fixed on 2021/03/10 01:48
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+9d3ede723bdc58553f13@syzkaller.appspotmail.com
Fix commit: 13384f6125ad kasan: fix null pointer dereference in kasan_record_aux_stack
First crash: 1248d, last: 1241d
Cause bisection: introduced by (bisect log) :
commit 97593cad003c668e2532cb2939a24a031f8de52d
Author: Andrey Konovalov <andreyknvl@google.com>
Date: Tue Dec 22 20:03:28 2020 +0000

  kasan: sanitize objects when metadata doesn't fit

Crash: BUG: unable to handle kernel NULL pointer dereference in call_rcu (log)
Repro: C syz .config
  
Discussions (1)
Title Replies (including bot) Last reply
BUG: unable to handle kernel NULL pointer dereference in call_rcu 4 (6) 2021/02/24 15:11
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2021/01/29 01:38 16m bisect fix upstream error job log (0)
Cause bisection attempts (2)
Created Duration User Patch Repo Result
2021/02/24 05:36 7h21m bisect upstream job log (1) log
2020/12/23 07:55 15m bisect upstream error job log (0)

Sample crash report:
BUG: kernel NULL pointer dereference, address: 0000000000000008
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 2d993067 P4D 2d993067 PUD 19a3c067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 3852 Comm: kworker/1:2 Not tainted 5.10.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events free_ipc
RIP: 0010:kasan_record_aux_stack+0x77/0xb0 mm/kasan/generic.c:341
Code: 48 f7 fe 8b 47 24 49 89 f0 48 29 d3 8d 70 ff 41 0f af f0 48 01 ce 48 39 f3 48 0f 46 f3 e8 81 e9 ff ff bf 00 08 00 00 48 89 c3 <8b> 40 08 89 43 0c e8 1e e6 ff ff 89 43 08 5b c3 48 8b 50 08 48 c7
RSP: 0018:ffffc90002e6fae8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888039800000
RDX: 0000000000000078 RSI: ffff888039800000 RDI: 0000000000000800
RBP: ffffffff837ef3a0 R08: 0000000000400000 R09: 000000000000002e
R10: ffffffff8132b7ea R11: 000000000000003f R12: 0000000000035b40
R13: ffff888039800088 R14: ffffc90002e6fc08 R15: 0000000000000200
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000008 CR3: 0000000011841000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __call_rcu kernel/rcu/tree.c:2965 [inline]
 call_rcu+0xbb/0x710 kernel/rcu/tree.c:3038
 ipc_rcu_putref+0x83/0xb0 ipc/util.c:505
 freeary+0x139c/0x1b30 ipc/sem.c:1188
 free_ipcs+0x98/0x1e0 ipc/namespace.c:112
 sem_exit_ns+0x1b/0x40 ipc/sem.c:260
 free_ipc_ns ipc/namespace.c:124 [inline]
 free_ipc+0xf8/0x200 ipc/namespace.c:141
 process_one_work+0x98d/0x1630 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
Modules linked in:
CR2: 0000000000000008
---[ end trace 28dc093e61d44dc2 ]---
RIP: 0010:kasan_record_aux_stack+0x77/0xb0 mm/kasan/generic.c:341
Code: 48 f7 fe 8b 47 24 49 89 f0 48 29 d3 8d 70 ff 41 0f af f0 48 01 ce 48 39 f3 48 0f 46 f3 e8 81 e9 ff ff bf 00 08 00 00 48 89 c3 <8b> 40 08 89 43 0c e8 1e e6 ff ff 89 43 08 5b c3 48 8b 50 08 48 c7
RSP: 0018:ffffc90002e6fae8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888039800000
RDX: 0000000000000078 RSI: ffff888039800000 RDI: 0000000000000800
RBP: ffffffff837ef3a0 R08: 0000000000400000 R09: 000000000000002e
R10: ffffffff8132b7ea R11: 000000000000003f R12: 0000000000035b40
R13: ffff888039800088 R14: ffffc90002e6fc08 R15: 0000000000000200
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000008 CR3: 0000000011841000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (85):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/12/23 02:33 upstream 614cb5894306 04201c06 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2020/12/23 02:17 upstream 614cb5894306 04201c06 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2020/12/23 02:06 upstream 614cb5894306 04201c06 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2020/12/29 23:59 upstream dea8dcf2a9fa 80910769 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/29 22:33 upstream dea8dcf2a9fa 80910769 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/29 15:23 upstream dea8dcf2a9fa 856f7b87 .config console log report info ci-qemu-upstream
2020/12/29 09:43 upstream dea8dcf2a9fa 8259d56c .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/29 06:49 upstream dea8dcf2a9fa 8259d56c .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/29 04:55 upstream dea8dcf2a9fa 8259d56c .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/28 20:50 upstream 5c8fe583cce5 8259d56c .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/28 19:27 upstream 5c8fe583cce5 8259d56c .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/28 17:34 upstream 5c8fe583cce5 8259d56c .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/28 16:32 upstream 5c8fe583cce5 8259d56c .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/28 14:54 upstream 5c8fe583cce5 8259d56c .config console log report info ci-qemu-upstream
2020/12/28 06:08 upstream 5c8fe583cce5 2242f77f .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/28 04:07 upstream 5c8fe583cce5 2242f77f .config console log report info ci-qemu-upstream
2020/12/27 19:39 upstream f838f8d2b694 2242f77f .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/27 16:58 upstream f838f8d2b694 2242f77f .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/27 15:41 upstream f838f8d2b694 2242f77f .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/27 14:11 upstream f838f8d2b694 2242f77f .config console log report info ci-qemu-upstream
2020/12/27 12:05 upstream f838f8d2b694 821e0b09 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/27 11:50 upstream f838f8d2b694 821e0b09 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/27 05:19 upstream f838f8d2b694 821e0b09 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/27 04:08 upstream f838f8d2b694 821e0b09 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/26 16:54 upstream 40f78232f973 821e0b09 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/26 15:30 upstream 40f78232f973 821e0b09 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/26 11:19 upstream 5814bc2d4cc2 821e0b09 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/26 10:06 upstream 5814bc2d4cc2 821e0b09 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/26 04:34 upstream 5814bc2d4cc2 821e0b09 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/26 03:08 upstream 5814bc2d4cc2 821e0b09 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/26 01:29 upstream 5814bc2d4cc2 821e0b09 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/26 00:20 upstream 5814bc2d4cc2 821e0b09 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 23:44 upstream 5814bc2d4cc2 b982b3ea .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 16:28 upstream 71c5f03154ac b982b3ea .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 16:06 upstream 71c5f03154ac b982b3ea .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 16:04 upstream 71c5f03154ac b982b3ea .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 16:04 upstream 71c5f03154ac b982b3ea .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 15:05 upstream 71c5f03154ac b982b3ea .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 15:05 upstream 71c5f03154ac b982b3ea .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 15:05 upstream 71c5f03154ac b982b3ea .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 13:39 upstream 71c5f03154ac b982b3ea .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 12:18 upstream 71c5f03154ac b982b3ea .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 11:19 upstream 71c5f03154ac b982b3ea .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 10:06 upstream 71c5f03154ac b982b3ea .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 03:26 upstream 3913d00ac51a c2c1d1dd .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 03:25 upstream 3913d00ac51a c2c1d1dd .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 01:59 upstream 3913d00ac51a c2c1d1dd .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/25 00:44 upstream 3913d00ac51a c2c1d1dd .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/22 23:21 upstream 614cb5894306 04201c06 .config console log report info ci-upstream-kasan-gce-selinux-root
* Struck through repros no longer work on HEAD.