syzbot
general protection fault in update_sit_entry
Status:
upstream: reported C repro on 2024/10/11 17:04
Bug presence:
origin:lts-only
[Documentation on labels]
Reported-by: syzbot+731f6e02febb1c3865b4@syzkaller.appspotmail.com
First crash: 650d, last: 43d
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Bug presence (2)
| Date |
Name |
Commit |
Repro |
Result |
| 2025/05/31 |
linux-5.15.y (ToT) |
98f47d0e9b8c |
C
|
[report] general protection fault in update_sit_entry
|
| 2025/05/31 |
upstream (ToT) |
0f70f5b08a47 |
C
|
Didn't crash |
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Last patch testing requests (10)
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Fix bisection attempts (6)
Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 PID: 4200 Comm: syz-executor482 Not tainted 5.15.184-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:2768 [inline]
RIP: 0010:update_sit_entry+0x626/0xf30 fs/f2fs/segment.c:2305
Code: 01 00 00 48 8d 5d 20 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 d7 ef 3e fe 48 8b 1b 4c 01 e3 48 89 d8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 ae 07 00 00 0f b6 2b 89 e8 44 8b 74 24
RSP: 0018:ffffc900030af020 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88801a583b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88814ca9a090 R08: ffff88801a583b80 R09: 0000000000000003
R10: 00000000ffffffff R11: 0000000000000000 R12: 0000000000000000
R13: ffff888077afc000 R14: ffff888075eec240 R15: dffffc0000000000
FS: 00007f6b08dd66c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000b000 CR3: 000000002b4a9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
f2fs_allocate_data_block+0x15fd/0x3610 fs/f2fs/segment.c:3432
do_write_page+0x156/0x6c0 fs/f2fs/segment.c:3520
f2fs_outplace_write_data+0xcb/0x1b0 fs/f2fs/segment.c:3586
f2fs_do_write_data_page+0xc0a/0x1230 fs/f2fs/data.c:2769
f2fs_write_single_data_page+0xfeb/0x1720 fs/f2fs/data.c:2893
f2fs_write_cache_pages fs/f2fs/data.c:3144 [inline]
__f2fs_write_data_pages fs/f2fs/data.c:3294 [inline]
f2fs_write_data_pages+0x15b3/0x26b0 fs/f2fs/data.c:3321
do_writepages+0x48d/0x6d0 mm/page-writeback.c:2386
filemap_fdatawrite_wbc+0x1eb/0x240 mm/filemap.c:400
__filemap_fdatawrite_range mm/filemap.c:433 [inline]
filemap_write_and_wait_range+0xfa/0x380 mm/filemap.c:704
f2fs_symlink+0x5f1/0x800 fs/f2fs/namei.c:662
vfs_symlink+0x247/0x3d0 fs/namei.c:4429
do_symlinkat+0x1be/0x6c0 fs/namei.c:4458
__do_sys_symlink fs/namei.c:4480 [inline]
__se_sys_symlink fs/namei.c:4478 [inline]
__x64_sys_symlink+0x7a/0x90 fs/namei.c:4478
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6b08e3ad89
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6b08dd6218 EFLAGS: 00000246 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007f6b08ec86b8 RCX: 00007f6b08e3ad89
RDX: 0000000000000000 RSI: 0000200000000cc0 RDI: 000020000000a900
RBP: 00007f6b08ec86b0 R08: 00007ffd0a39c967 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000020000000a900
R13: 0000200000000cc0 R14: 00007ffd0a39c880 R15: 0000200000000100
</TASK>
Modules linked in:
---[ end trace a0204b00e34aa443 ]---
RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:2768 [inline]
RIP: 0010:update_sit_entry+0x626/0xf30 fs/f2fs/segment.c:2305
Code: 01 00 00 48 8d 5d 20 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 d7 ef 3e fe 48 8b 1b 4c 01 e3 48 89 d8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 ae 07 00 00 0f b6 2b 89 e8 44 8b 74 24
RSP: 0018:ffffc900030af020 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88801a583b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88814ca9a090 R08: ffff88801a583b80 R09: 0000000000000003
R10: 00000000ffffffff R11: 0000000000000000 R12: 0000000000000000
R13: ffff888077afc000 R14: ffff888075eec240 R15: dffffc0000000000
FS: 00007f6b08dd66c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6b08e8e898 CR3: 000000002b4a9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 01 00 add %eax,(%rax)
2: 00 48 8d add %cl,-0x73(%rax)
5: 5d pop %rbp
6: 20 48 89 and %cl,-0x77(%rax)
9: d8 48 c1 fmuls -0x3f(%rax)
c: e8 03 42 80 3c call 0x3c804214
11: 38 00 cmp %al,(%rax)
13: 74 08 je 0x1d
15: 48 89 df mov %rbx,%rdi
18: e8 d7 ef 3e fe call 0xfe3eeff4
1d: 48 8b 1b mov (%rbx),%rbx
20: 4c 01 e3 add %r12,%rbx
23: 48 89 d8 mov %rbx,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 0f b6 04 38 movzbl (%rax,%r15,1),%eax <-- trapping instruction
2f: 84 c0 test %al,%al
31: 0f 85 ae 07 00 00 jne 0x7e5
37: 0f b6 2b movzbl (%rbx),%ebp
3a: 89 e8 mov %ebp,%eax
3c: 44 rex.R
3d: 8b .byte 0x8b
3e: 74 24 je 0x64
* Struck through repros no longer work on HEAD.