syzbot


general protection fault in loop_process_work

Status: auto-obsoleted due to no activity on 2023/10/06 02:37
Subsystems: block
[Documentation on labels]
Reported-by: syzbot+1e0c0f6fa11e5acdd9af@syzkaller.appspotmail.com
First crash: 570d, last: 570d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in loop_process_work (2) block 1 463d 459d 0/28 auto-obsoleted due to no activity on 2024/01/21 18:59

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000032: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000190-0x0000000000000197]
CPU: 1 PID: 8868 Comm: kworker/u4:12 Not tainted 6.4.0-syzkaller-12316-g4f6b6c2b2f86 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Workqueue: loop3 loop_workfn
RIP: 0010:lo_write_bvec drivers/block/loop.c:248 [inline]
RIP: 0010:lo_write_simple drivers/block/loop.c:271 [inline]
RIP: 0010:do_req_filebacked drivers/block/loop.c:495 [inline]
RIP: 0010:loop_handle_cmd drivers/block/loop.c:1886 [inline]
RIP: 0010:loop_process_work+0x101c/0x20a0 drivers/block/loop.c:1921
Code: 01 00 00 00 be 01 00 00 00 48 8b 54 24 48 48 8b 7c 24 18 48 8b 68 60 e8 92 57 e6 fe 4c 8d a5 90 01 00 00 4c 89 e0 48 c1 e8 03 <42> 80 3c 38 00 0f 85 5e 0c 00 00 4c 8b b5 90 01 00 00 4c 89 f0 48
RSP: 0018:ffffc9000530fb30 EFLAGS: 00010212
RAX: 0000000000000032 RBX: 0000000000001000 RCX: 0000000000000000
RDX: 1ffff92000a61f93 RSI: 1ffff92000a61f01 RDI: ffffc9000530fc98
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000190
R13: ffffea0000a86f40 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555558d3848 CR3: 000000007bb2c000 CR4: 0000000000350ee0
Call Trace:
 <TASK>
 process_one_work+0xa34/0x16f0 kernel/workqueue.c:2597
 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2748
 kthread+0x344/0x440 kernel/kthread.c:389
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:lo_write_bvec drivers/block/loop.c:248 [inline]
RIP: 0010:lo_write_simple drivers/block/loop.c:271 [inline]
RIP: 0010:do_req_filebacked drivers/block/loop.c:495 [inline]
RIP: 0010:loop_handle_cmd drivers/block/loop.c:1886 [inline]
RIP: 0010:loop_process_work+0x101c/0x20a0 drivers/block/loop.c:1921
Code: 01 00 00 00 be 01 00 00 00 48 8b 54 24 48 48 8b 7c 24 18 48 8b 68 60 e8 92 57 e6 fe 4c 8d a5 90 01 00 00 4c 89 e0 48 c1 e8 03 <42> 80 3c 38 00 0f 85 5e 0c 00 00 4c 8b b5 90 01 00 00 4c 89 f0 48
RSP: 0018:ffffc9000530fb30 EFLAGS: 00010212
RAX: 0000000000000032 RBX: 0000000000001000 RCX: 0000000000000000
RDX: 1ffff92000a61f93 RSI: 1ffff92000a61f01 RDI: ffffc9000530fc98
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000190
R13: ffffea0000a86f40 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7bc6ffb000 CR3: 000000002f8b6000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
   0:	01 00                	add    %eax,(%rax)
   2:	00 00                	add    %al,(%rax)
   4:	be 01 00 00 00       	mov    $0x1,%esi
   9:	48 8b 54 24 48       	mov    0x48(%rsp),%rdx
   e:	48 8b 7c 24 18       	mov    0x18(%rsp),%rdi
  13:	48 8b 68 60          	mov    0x60(%rax),%rbp
  17:	e8 92 57 e6 fe       	callq  0xfee657ae
  1c:	4c 8d a5 90 01 00 00 	lea    0x190(%rbp),%r12
  23:	4c 89 e0             	mov    %r12,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 38 00       	cmpb   $0x0,(%rax,%r15,1) <-- trapping instruction
  2f:	0f 85 5e 0c 00 00    	jne    0xc93
  35:	4c 8b b5 90 01 00 00 	mov    0x190(%rbp),%r14
  3c:	4c 89 f0             	mov    %r14,%rax
  3f:	48                   	rex.W

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/07/08 02:37 upstream 4f6b6c2b2f86 668cb1fa .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root general protection fault in loop_process_work
* Struck through repros no longer work on HEAD.