syzbot


general protection fault in sysfs_move_dir_ns

Status: upstream: reported on 2026/05/13 10:40
Reported-by: syzbot+0208e28be8483d1576f2@syzkaller.appspotmail.com
First crash: 19h30m, last: 19h30m
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 general protection fault in sysfs_move_dir_ns 2 1 4d10h 4d10h 0/3 upstream: reported on 2026/05/09 19:51
upstream general protection fault in sysfs_move_dir_ns fs 2 10 408d 530d 0/29 auto-obsoleted due to no activity on 2025/06/30 00:17

Sample crash report:
EXT4-fs error (device loop4): htree_dirblock_to_tree:1112: inode #2: block 13: comm syz-executor: bad entry in directory: rec_len is smaller than minimal - offset=24, inode=11, rec_len=8, size=1024 fake=0
general protection fault, probably for non-canonical address 0xdffffc0000000007: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]
CPU: 0 PID: 4202 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:sysfs_move_dir_ns+0xa6/0xd0 fs/sysfs/dir.c:127
Code: 96 48 c1 e8 03 42 80 3c 20 00 74 0c 48 c7 c7 20 f4 3a 96 e8 ac 4c d0 ff 4c 8b 3d 65 ed 4c 14 49 8d 7e 38 48 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 05 e8 8e 4c d0 ff 49 8b 56 38 4c 89 f7 4c 89 fe
RSP: 0018:ffffc9000331f9b8 EFLAGS: 00010202
RAX: 0000000000000007 RBX: 0000000000000000 RCX: ffff8880638e0000
RDX: 0000000000000000 RSI: ffff88801bc35800 RDI: 0000000000000038
RBP: ffffc9000331fa88 R08: ffff8880638e0000 R09: 0000000000000012
R10: 0000000000000012 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888073077500 R14: 0000000000000000 R15: ffff888141f85bc8
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556affe9f8 CR3: 0000000063d67000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kobject_move+0x546/0x700 lib/kobject.c:593
 device_move+0xdc/0x6f0 drivers/base/core.c:4329
 hci_conn_del_sysfs+0xab/0x160 net/bluetooth/hci_sysfs.c:73
 hci_conn_cleanup+0x4d1/0x680 net/bluetooth/hci_conn.c:140
 hci_conn_del+0x2ab/0x3e0 net/bluetooth/hci_conn.c:678
 hci_conn_hash_flush+0x185/0x220 net/bluetooth/hci_conn.c:1623
 hci_dev_do_close+0x991/0x1030 net/bluetooth/hci_core.c:1795
 hci_unregister_dev+0x2d7/0x580 net/bluetooth/hci_core.c:4044
 vhci_release+0x73/0xc0 drivers/bluetooth/hci_vhci.c:345
 __fput+0x234/0x930 fs/file_table.c:311
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 exit_task_work include/linux/task_work.h:33 [inline]
 do_exit+0x626/0x20c0 kernel/exit.c:883
 do_group_exit+0x12e/0x300 kernel/exit.c:997
 __do_sys_exit_group kernel/exit.c:1008 [inline]
 __se_sys_exit_group kernel/exit.c:1006 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
 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: 0033:0x7ffa523b9e59
Code: Unable to access opcode bytes at RIP 0x7ffa523b9e2f.
RSP: 002b:00007ffe35653418 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007ffa5244f23c RCX: 00007ffa523b9e59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000010 R08: 0000000000000000 R09: 00007ffa5244f1ca
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe356546d0
R13: 00007ffa5244f1ca R14: 000055556cba64e8 R15: 00007ffe356557a0
 </TASK>
Modules linked in:
---[ end trace 44c064040bd5c8fc ]---
RIP: 0010:sysfs_move_dir_ns+0xa6/0xd0 fs/sysfs/dir.c:127
Code: 96 48 c1 e8 03 42 80 3c 20 00 74 0c 48 c7 c7 20 f4 3a 96 e8 ac 4c d0 ff 4c 8b 3d 65 ed 4c 14 49 8d 7e 38 48 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 05 e8 8e 4c d0 ff 49 8b 56 38 4c 89 f7 4c 89 fe
RSP: 0018:ffffc9000331f9b8 EFLAGS: 00010202
RAX: 0000000000000007 RBX: 0000000000000000 RCX: ffff8880638e0000
RDX: 0000000000000000 RSI: ffff88801bc35800 RDI: 0000000000000038
RBP: ffffc9000331fa88 R08: ffff8880638e0000 R09: 0000000000000012
R10: 0000000000000012 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888073077500 R14: 0000000000000000 R15: ffff888141f85bc8
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559797395950 CR3: 000000007e160000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	96                   	xchg   %eax,%esi
   1:	48 c1 e8 03          	shr    $0x3,%rax
   5:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1)
   a:	74 0c                	je     0x18
   c:	48 c7 c7 20 f4 3a 96 	mov    $0xffffffff963af420,%rdi
  13:	e8 ac 4c d0 ff       	call   0xffd04cc4
  18:	4c 8b 3d 65 ed 4c 14 	mov    0x144ced65(%rip),%r15        # 0x144ced84
  1f:	49 8d 7e 38          	lea    0x38(%r14),%rdi
  23:	48 89 f8             	mov    %rdi,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1) <-- trapping instruction
  2f:	74 05                	je     0x36
  31:	e8 8e 4c d0 ff       	call   0xffd04cc4
  36:	49 8b 56 38          	mov    0x38(%r14),%rdx
  3a:	4c 89 f7             	mov    %r14,%rdi
  3d:	4c 89 fe             	mov    %r15,%rsi

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/13 10:40 linux-5.15.y de8dfb3f0278 fec2a7ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan general protection fault in sysfs_move_dir_ns
* Struck through repros no longer work on HEAD.