syzbot


kernel panic: panic_on_warn set

Status: closed as invalid on 2021/08/23 09:16
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 525d, last: 525d

Cause bisection: failed (bisect log)
similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream kernel panic: panic_on_warn set (4) syz error 2 504d 504d 0/24 closed as invalid on 2021/09/13 11:45
android-54 kernel panic: panic_on_warn set C 52 693d 791d 0/2 upstream: reported C repro on 2020/11/27 15:20
upstream kernel panic: panic_on_warn set (3) syz error 1 506d 505d 0/24 closed as invalid on 2021/09/10 07:34
upstream kernel panic: panic_on_warn set (2) syz error 1 507d 507d 0/24 closed as invalid on 2021/09/08 09:41

Sample crash report:
 handle drivers/base/devtmpfs.c:382 [inline]
 devtmpfs_work_loop drivers/base/devtmpfs.c:395 [inline]
 devtmpfsd+0x1ba/0x2ab drivers/base/devtmpfs.c:437
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 22 Comm: kdevtmpfs Not tainted 5.14.0-rc6-next-20210820-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 panic+0x2af/0x6d5 kernel/panic.c:232
 kfence_report_error.cold+0x30b/0xa76 mm/kfence/report.c:271
 kfence_handle_page_fault+0x205/0x640 mm/kfence/core.c:883
 page_fault_oops+0x1c5/0x6b0 arch/x86/mm/fault.c:686
 kernelmode_fixup_or_oops+0x221/0x280 arch/x86/mm/fault.c:755
 __bad_area_nosemaphore+0x372/0x400 arch/x86/mm/fault.c:801
 do_kern_addr_fault+0x5f/0x80 arch/x86/mm/fault.c:1200
 handle_page_fault arch/x86/mm/fault.c:1473 [inline]
 exc_page_fault+0x155/0x180 arch/x86/mm/fault.c:1531
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:568
RIP: 0010:kvm_fastop_exception+0xf68/0x1056
Code: d3 ed e9 e4 91 6d f8 49 8d 0e 48 83 e1 f8 4c 8b 21 41 8d 0e 83 e1 07 c1 e1 03 49 d3 ec e9 3f 9f 6d f8 49 8d 4d 00 48 83 e1 f8 <4c> 8b 21 41 8d 4d 00 83 e1 07 c1 e1 03 49 d3 ec e9 39 a9 6d f8 bd
RSP: 0018:ffffc90000dcfaa8 EFLAGS: 00010282
RAX: 0000000035736376 RBX: ffff88806df67358 RCX: ffff88823bd14020
RDX: ffffed100dbece72 RSI: 0000000000000004 RDI: 0000000000000007
RBP: 0000000000000004 R08: 0000000000000000 R09: ffff88806df67388
R10: ffffed100dbece71 R11: 0000000000000000 R12: ffff88823bd14020
R13: ffff88823bd14020 R14: ffff88806df67388 R15: dffffc0000000000
 d_lookup+0xdd/0x170 fs/dcache.c:2370
 lookup_dcache+0x1e/0x130 fs/namei.c:1520
 __lookup_hash+0x29/0x180 fs/namei.c:1543
 kern_path_locked+0x17e/0x320 fs/namei.c:2567
 handle_remove+0xa2/0x5fe drivers/base/devtmpfs.c:312
 handle drivers/base/devtmpfs.c:382 [inline]
 devtmpfs_work_loop drivers/base/devtmpfs.c:395 [inline]
 devtmpfsd+0x1ba/0x2ab drivers/base/devtmpfs.c:437
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Kernel Offset: disabled
----------------
Code disassembly (best guess):
   0:	d3 ed                	shr    %cl,%ebp
   2:	e9 e4 91 6d f8       	jmpq   0xf86d91eb
   7:	49 8d 0e             	lea    (%r14),%rcx
   a:	48 83 e1 f8          	and    $0xfffffffffffffff8,%rcx
   e:	4c 8b 21             	mov    (%rcx),%r12
  11:	41 8d 0e             	lea    (%r14),%ecx
  14:	83 e1 07             	and    $0x7,%ecx
  17:	c1 e1 03             	shl    $0x3,%ecx
  1a:	49 d3 ec             	shr    %cl,%r12
  1d:	e9 3f 9f 6d f8       	jmpq   0xf86d9f61
  22:	49 8d 4d 00          	lea    0x0(%r13),%rcx
  26:	48 83 e1 f8          	and    $0xfffffffffffffff8,%rcx
* 2a:	4c 8b 21             	mov    (%rcx),%r12 <-- trapping instruction
  2d:	41 8d 4d 00          	lea    0x0(%r13),%ecx
  31:	83 e1 07             	and    $0x7,%ecx
  34:	c1 e1 03             	shl    $0x3,%ecx
  37:	49 d3 ec             	shr    %cl,%r12
  3a:	e9 39 a9 6d f8       	jmpq   0xf86da978
  3f:	bd                   	.byte 0xbd

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci-upstream-linux-next-kasan-gce-root 2021/08/21 05:04 linux-next 86ed57fd8c93 b599f2fc .config console log report syz kernel panic: panic_on_warn set
* Struck through repros no longer work on HEAD.