syzbot


general protection fault in update_sit_entry

Status: upstream: reported C repro on 2024/12/08 18:16
Bug presence: origin:downstream
[Documentation on labels]
Reported-by: syzbot+5befe124e5915c6e2b0f@syzkaller.appspotmail.com
First crash: 181d, last: 12d
Bug presence (3)
Date Name Commit Repro Result
2024/12/09 android14-6.1 (ToT) c276c53965a8 C [report] general protection fault in update_sit_entry
2024/12/09 lts (merge base) 0d968ced7330 C Didn't crash
2024/12/09 upstream (ToT) fac04efc5c79 C Didn't crash
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 general protection fault in update_sit_entry origin:lts-only C error 18 7d05h 239d 0/3 upstream: reported C repro on 2024/10/11 17:04
linux-4.14 general protection fault in update_sit_entry f2fs C 9 825d 938d 0/1 upstream: reported C repro on 2022/11/12 02:17
android-5-10 general protection fault in update_sit_entry C 11 1d03h 190d 0/2 upstream: reported C repro on 2024/11/29 11:40
linux-6.1 general protection fault in update_sit_entry origin:lts-only C done 6 30d 151d 0/3 upstream: reported C repro on 2025/01/07 01:40
android-5-15 general protection fault in update_sit_entry origin:downstream C 11 4d13h 195d 0/2 upstream: reported C repro on 2024/11/24 02:28
Last patch testing requests (4)
Created Duration User Patch Repo Result
2025/03/21 04:37 11m retest repro android14-6.1 report log
2025/03/21 04:37 6m retest repro android14-6.1 report log
2024/12/26 11:37 7m retest repro android14-6.1 report log
2024/12/26 11:37 6m retest repro android14-6.1 report log
Fix bisection attempts (3)
Created Duration User Patch Repo Result
2025/04/25 04:32 2h46m bisect fix android14-6.1 OK (0) job log log
2025/03/05 01:17 1h12m bisect fix android14-6.1 OK (0) job log log
2025/01/31 09:30 1h20m bisect fix android14-6.1 OK (0) job log log

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: 292 Comm: syz-executor290 Not tainted 6.1.134-syzkaller-00039-g3c6d0251e1fb #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:2940 [inline]
RIP: 0010:update_sit_entry_for_alloc fs/f2fs/segment.c:2396 [inline]
RIP: 0010:update_sit_entry+0x4f9/0x15a0 fs/f2fs/segment.c:2440
Code: 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 ae 1c 8d ff 48 8b 1b 4c 01 f3 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 0f 85 55 0f 00 00 44 0f b6 23 44 89 e0 44 08 f8
RSP: 0018:ffffc90000eb71e0 EFLAGS: 00010247
RAX: 0000000000000000 RBX: 0000000000000004 RCX: dffffc0000000000
RDX: ffff88810e63d100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000eb72b0 R08: ffff88810e63d100 R09: 0000000000000003
R10: 00000000ffffffff R11: 0000000000000000 R12: 0000000000000000
R13: ffff88810d9440c8 R14: 0000000000000004 R15: 0000000000000008
FS:  00007f3709de76c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3702221000 CR3: 0000000124f14000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 f2fs_allocate_data_block+0x148c/0x3af0 fs/f2fs/segment.c:3430
 __allocate_data_block fs/f2fs/data.c:1488 [inline]
 f2fs_map_blocks+0x11a8/0x3a60 fs/f2fs/data.c:1671
 f2fs_expand_inode_data+0x639/0xa70 fs/f2fs/file.c:1847
 f2fs_fallocate+0x3cc/0x720 fs/f2fs/file.c:1948
 vfs_fallocate+0x4c5/0x5a0 fs/open.c:324
 ioctl_preallocate fs/ioctl.c:290 [inline]
 file_ioctl fs/ioctl.c:-1 [inline]
 do_vfs_ioctl+0x1a1d/0x1c80 fs/ioctl.c:849
 __do_sys_ioctl fs/ioctl.c:868 [inline]
 __se_sys_ioctl+0x9f/0x1b0 fs/ioctl.c:856
 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856
 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f3709e2a739
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 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:00007f3709de7218 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f3709eb6608 RCX: 00007f3709e2a739
RDX: 00002000000000c0 RSI: 0000000040305828 RDI: 0000000000000004
RBP: 00007f3709eb6600 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3709e835f0
R13: 00002000000000c0 R14: 00002000000000e0 R15: 0000200000000000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:2940 [inline]
RIP: 0010:update_sit_entry_for_alloc fs/f2fs/segment.c:2396 [inline]
RIP: 0010:update_sit_entry+0x4f9/0x15a0 fs/f2fs/segment.c:2440
Code: 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 ae 1c 8d ff 48 8b 1b 4c 01 f3 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 0f 85 55 0f 00 00 44 0f b6 23 44 89 e0 44 08 f8
RSP: 0018:ffffc90000eb71e0 EFLAGS: 00010247
RAX: 0000000000000000 RBX: 0000000000000004 RCX: dffffc0000000000
RDX: ffff88810e63d100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000eb72b0 R08: ffff88810e63d100 R09: 0000000000000003
R10: 00000000ffffffff R11: 0000000000000000 R12: 0000000000000000
R13: ffff88810d9440c8 R14: 0000000000000004 R15: 0000000000000008
FS:  00007f3709de76c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3702470000 CR3: 0000000124f14000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 4 bytes skipped:
   0:	df 80 3c 08 00 74    	filds  0x7400083c(%rax)
   6:	08 48 89             	or     %cl,-0x77(%rax)
   9:	df e8                	fucomip %st(0),%st
   b:	ae                   	scas   %es:(%rdi),%al
   c:	1c 8d                	sbb    $0x8d,%al
   e:	ff 48 8b             	decl   -0x75(%rax)
  11:	1b 4c 01 f3          	sbb    -0xd(%rcx,%rax,1),%ecx
  15:	48 89 d8             	mov    %rbx,%rax
  18:	48 c1 e8 03          	shr    $0x3,%rax
  1c:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  23:	fc ff df
* 26:	0f b6 04 08          	movzbl (%rax,%rcx,1),%eax <-- trapping instruction
  2a:	84 c0                	test   %al,%al
  2c:	0f 85 55 0f 00 00    	jne    0xf87
  32:	44 0f b6 23          	movzbl (%rbx),%r12d
  36:	44 89 e0             	mov    %r12d,%eax
  39:	44 08 f8             	or     %r15b,%al

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/26 07:00 android14-6.1 3c6d0251e1fb 2d4582d0 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-android-6-1 general protection fault in update_sit_entry
2024/12/08 19:26 android14-6.1 c276c53965a8 9ac0fdc6 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 general protection fault in update_sit_entry
2024/12/08 18:51 android14-6.1 c276c53965a8 9ac0fdc6 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 general protection fault in update_sit_entry
2024/12/08 18:12 android14-6.1 c276c53965a8 9ac0fdc6 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 general protection fault in update_sit_entry
2024/12/28 19:34 android14-6.1 3f924195e222 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in update_sit_entry
2024/12/28 19:33 android14-6.1 3f924195e222 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in update_sit_entry
2024/12/08 22:06 android14-6.1 c276c53965a8 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in update_sit_entry
2024/12/08 17:38 android14-6.1 c276c53965a8 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in update_sit_entry
* Struck through repros no longer work on HEAD.