general protection fault in start_dirop

Status: upstream: reported C repro on 2026/07/29 00:19
Subsystems: usb fs
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+1e3d934ee3cff1ac188b@syzkaller.appspotmail.com
First crash: 54d, last: 18d
▶ ▼ ✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
b2073c69 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ general protection fault in start_dirop 2026/07/25 00:43 2026/07/25 00:43 2026/07/25 01:33 1bdb5c57
▶ ▼ Discussions (2)
Title Replies (including bot) Last reply
[PATCH] i2c: fix use-after-free in debugfs directory during adapter removal 3 (3) 2026/08/01 03:49
[syzbot] [fs?] general protection fault in start_dirop 0 (4) 2026/07/29 14:59
▶ ▼ Last patch testing requests (8)
Created Duration User Patch Repo Result
2026/09/16 07:52 8m retest repro linux-next error job log
2026/09/12 22:05 20m retest repro upstream no crash job log log
2026/09/12 22:05 19m retest repro upstream no crash job log log
2026/09/12 22:05 19m retest repro upstream no crash job log log
2026/09/12 22:05 21m retest repro upstream no crash job log log
2026/07/29 14:59 26m yun.zhou@windriver.com patch upstream OK log
2026/07/29 13:59 27m yun.zhou@windriver.com patch upstream OK log
2026/07/29 08:32 26m dmantipov@yandex.ru patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git fc02acf6ac0ccde0c805c2daa9148683cdd01ba8 report log

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000028: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000140-0x0000000000000147]
CPU: 1 UID: 0 PID: 6333 Comm: syz.0.101 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:kasan_byte_accessible+0x12/0x30 mm/kasan/generic.c:210
Code: 79 ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 c1 ef 03 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 07 3c 08 0f 92 c0 c3 cc cc cc cc cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc90005a0f368 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffffffff81a2e9bd RCX: 8000000000000001
RDX: 0000000000000000 RSI: ffffffff81a2e9bd RDI: 0000000000000028
RBP: ffffc90005a0f4a8 R08: 0000000000000001 R09: 0000000000000000
R10: 000000000000002f R11: 0000000000000000 R12: 0000000000000140
R13: 0000000000000000 R14: 0000000000000140 R15: 0000000000000001
FS:  000055555f967500(0000) GS:ffff88812498a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30763fff CR3: 000000006a536000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 __kasan_check_byte+0x12/0x40 mm/kasan/common.c:573
 kasan_check_byte include/linux/kasan.h:402 [inline]
 lock_acquire+0x7d/0x350 kernel/locking/lockdep.c:5882
 down_write_nested+0x9d/0x210 kernel/locking/rwsem.c:1757
 inode_lock_nested include/linux/fs.h:1069 [inline]
 __start_dirop fs/namei.c:2918 [inline]
 start_dirop+0x4f/0x90 fs/namei.c:2942
 simple_start_creating+0xcc/0x110 fs/libfs.c:2308
 debugfs_start_creating+0xca/0x1b0 fs/debugfs/inode.c:397
 debugfs_create_dir+0x24/0x350 fs/debugfs/inode.c:575
 i2c_device_probe+0x814/0xbf0 drivers/i2c/i2c-core-base.c:589
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x254/0xae0 drivers/base/dd.c:706
 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
 __device_attach_driver+0x270/0x410 drivers/base/dd.c:1026
 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
 __device_attach+0x2c4/0x450 drivers/base/dd.c:1098
 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x12a/0x220 drivers/base/bus.c:620
 device_add+0x7d7/0xb80 drivers/base/core.c:3776
 i2c_new_client_device+0xa29/0x1130 drivers/i2c/i2c-core-base.c:1020
 new_device_store+0x24b/0x530 drivers/i2c/i2c-core-base.c:1308
 kernfs_fop_write_iter+0x3a4/0x540 fs/kernfs/file.c:345
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x612/0xba0 fs/read_write.c:687
 ksys_write+0x150/0x270 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe59319e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdfaea9088 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fe593425fa0 RCX: 00007fe59319e0d9
RDX: 000000000000000c RSI: 0000200000000280 RDI: 0000000000000004
RBP: 00007fe593235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe593425fac R14: 00007fe593425fa0 R15: 00007fe593425fa0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:kasan_byte_accessible+0x12/0x30 mm/kasan/generic.c:210
Code: 79 ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 c1 ef 03 48 b8 00 00 00 00 00 fc ff df <0f> 
Code: 79 ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 c1 ef 03 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 07 3c 08 0f 92 c0 c3 cc cc cc cc cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc90005a0f368 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffffffff81a2e9bd RCX: 8000000000000001
RDX: 0000000000000000 RSI: ffffffff81a2e9bd RDI: 0000000000000028
RBP: ffffc90005a0f4a8 R08: 0000000000000001 R09: 0000000000000000
R10: 000000000000002f R11: 0000000000000000 R12: 0000000000000140
R13: 0000000000000000 R14: 0000000000000140 R15: 0000000000000001
FS:  000055555f967500(0000) GS:ffff88812488a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7eceaa6fb3 CR3: 000000006a536000 CR4: 00000000003526f0
----------------
Code disassembly (best guess), 4 bytes skipped:
   0:	0f 1f 40 00          	nopl   0x0(%rax)
   4:	90                   	nop
   5:	90                   	nop
   6:	90                   	nop
   7:	90                   	nop
   8:	90                   	nop
   9:	90                   	nop
   a:	90                   	nop
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	0f 1f 40 d6          	nopl   -0x2a(%rax)
  18:	48 c1 ef 03          	shr    $0x3,%rdi
  1c:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  23:	fc ff df
* 26:	0f b6 04 07          	movzbl (%rdi,%rax,1),%eax <-- trapping instruction
  2a:	3c 08                	cmp    $0x8,%al
  2c:	0f 92 c0             	setb   %al
  2f:	c3                   	ret
  30:	cc                   	int3
  31:	cc                   	int3
  32:	cc                   	int3
  33:	cc                   	int3
  34:	cc                   	int3
  35:	66                   	data16
  36:	66                   	data16
  37:	66                   	data16
  38:	66                   	data16
  39:	66                   	data16
  3a:	66                   	data16
  3b:	2e                   	cs

Crashes (20):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/23 15:03 linux-next 903c1cf6dff9 1e72964b .config strace log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce general protection fault in start_dirop
2026/08/27 17:37 upstream 73e3f0710014 e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root general protection fault in start_dirop
2026/08/26 12:32 upstream 73ae59e97596 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root general protection fault in start_dirop
2026/08/26 10:15 upstream 73ae59e97596 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root general protection fault in start_dirop
2026/08/12 11:59 upstream f5bbbfec59b4 f8d35649 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in start_dirop
2026/08/12 11:57 upstream f5bbbfec59b4 f8d35649 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in start_dirop
2026/08/04 14:46 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root general protection fault in start_dirop
2026/07/24 23:11 upstream 48a5a7ab8d6a 05b26a28 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in start_dirop
2026/08/29 21:42 upstream 08dbfad3f504 2f52988a .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_dirop
2026/08/28 20:22 upstream 818bebeb63dd 41d151d4 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_dirop
2026/08/27 15:33 upstream 818bebeb63dd c53a1b9c .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_dirop
2026/08/24 16:59 upstream 818bebeb63dd b55bd4c3 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in start_dirop
2026/08/22 11:34 upstream 818bebeb63dd 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in start_dirop
2026/07/28 04:10 upstream 62cc90241548 4a865b71 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_dirop
2026/07/26 16:18 upstream 3dab139d4795 4a865b71 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_dirop
2026/07/26 03:24 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_dirop
2026/07/25 01:25 upstream 48a5a7ab8d6a 4a865b71 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_dirop
2026/07/24 23:19 upstream 48a5a7ab8d6a 4a865b71 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_dirop
2026/07/24 22:03 upstream 48a5a7ab8d6a 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_dirop
2026/07/28 13:49 upstream 62cc90241548 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in start_dirop
* Struck through repros no longer work on HEAD.