Re: [syzbot] [erofs?] WARNING in rmqueue
From: syzbot
Date: Mon Apr 10 2023 - 05:26:32 EST
Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
BUG: unable to handle kernel paging request in z_erofs_decompress_queue
BUG: unable to handle page fault for address: fffff52101a3fff9
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 23ffed067 P4D 23ffed067 PUD 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 4398 Comm: kworker/u5:1 Not tainted 6.3.0-rc6-syzkaller-g09a9639e56c0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
Workqueue: erofs_worker z_erofs_decompressqueue_work
RIP: 0010:z_erofs_decompress_queue+0xb7e/0x2b40
Code: 0a 48 8b 7c 24 68 e8 51 fe 00 fe 89 db 48 c1 e3 03 48 03 9c 24 20 03 00 00 49 89 de 49 c1 ee 03 48 b8 00 00 00 00 00 fc ff df <41> 80 3c 06 00 74 08 48 89 df e8 23 fe 00 fe 48 83 3b 00 0f 84 a1
RSP: 0018:ffffc90006a5f7c0 EFLAGS: 00010a06
RAX: dffffc0000000000 RBX: ffffc9080d1fffc8 RCX: 1ffff92000d4bf5c
RDX: ffff88802b800000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90006a5fbb0 R08: ffffffff83ddecfa R09: fffff52001a40000
R10: 0000000000000000 R11: dffffc0000000001 R12: 00000000ffff8f00
R13: ffff888073fad0b8 R14: 1ffff92101a3fff9 R15: ffffea0001b54b40
FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffff52101a3fff9 CR3: 000000002b4b9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
z_erofs_decompressqueue_work+0x99/0xe0
process_one_work+0x8f6/0x1170
worker_thread+0xa63/0x1210
kthread+0x270/0x300
ret_from_fork+0x1f/0x30
</TASK>
Modules linked in:
CR2: fffff52101a3fff9
---[ end trace 0000000000000000 ]---
RIP: 0010:z_erofs_decompress_queue+0xb7e/0x2b40
Code: 0a 48 8b 7c 24 68 e8 51 fe 00 fe 89 db 48 c1 e3 03 48 03 9c 24 20 03 00 00 49 89 de 49 c1 ee 03 48 b8 00 00 00 00 00 fc ff df <41> 80 3c 06 00 74 08 48 89 df e8 23 fe 00 fe 48 83 3b 00 0f 84 a1
RSP: 0018:ffffc90006a5f7c0 EFLAGS: 00010a06
RAX: dffffc0000000000 RBX: ffffc9080d1fffc8 RCX: 1ffff92000d4bf5c
RDX: ffff88802b800000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90006a5fbb0 R08: ffffffff83ddecfa R09: fffff52001a40000
R10: 0000000000000000 R11: dffffc0000000001 R12: 00000000ffff8f00
R13: ffff888073fad0b8 R14: 1ffff92101a3fff9 R15: ffffea0001b54b40
FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffff52101a3fff9 CR3: 000000002b4b9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 48 8b 7c 24 68 mov 0x68(%rsp),%rdi
5: e8 51 fe 00 fe callq 0xfe00fe5b
a: 89 db mov %ebx,%ebx
c: 48 c1 e3 03 shl $0x3,%rbx
10: 48 03 9c 24 20 03 00 add 0x320(%rsp),%rbx
17: 00
18: 49 89 de mov %rbx,%r14
1b: 49 c1 ee 03 shr $0x3,%r14
1f: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
26: fc ff df
* 29: 41 80 3c 06 00 cmpb $0x0,(%r14,%rax,1) <-- trapping instruction
2e: 74 08 je 0x38
30: 48 89 df mov %rbx,%rdi
33: e8 23 fe 00 fe callq 0xfe00fe5b
38: 48 83 3b 00 cmpq $0x0,(%rbx)
3c: 0f .byte 0xf
3d: 84 .byte 0x84
3e: a1 .byte 0xa1
Tested on:
commit: 09a9639e Linux 6.3-rc6
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ v6.3-rc6
console output: https://syzkaller.appspot.com/x/log.txt?x=1125d353c80000
kernel config: https://syzkaller.appspot.com/x/.config?x=174dd96f08254844
dashboard link: https://syzkaller.appspot.com/bug?extid=aafb3f37cfeb6534c4ac
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
Note: no patches were applied.