syzbot


general protection fault in smack_inode_permission (3)

Status: moderation: reported on 2025/11/07 02:43
Subsystems: lsm
[Documentation on labels]
Reported-by: syzbot+8562ac68bd1e885da59f@syzkaller.appspotmail.com
First crash: 51d, last: 4d18h
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in smack_inode_permission lsm 8 13 343d 597d 0/29 auto-obsoleted due to no activity on 2025/04/25 12:24
upstream general protection fault in smack_inode_permission (2) lsm 2 1 169d 165d 0/29 auto-obsoleted due to no activity on 2025/10/05 23:45
upstream BUG: unable to handle kernel NULL pointer dereference in smack_inode_permission lsm mm 10 C 1 1140d 1136d 22/29 fixed on 2023/02/24 13:50

Sample crash report:
ERROR: (device loop4): jfs_readdir: JFS:Dtree error: ino = 2, bn=0, index = 6
ERROR: (device loop4): jfs_readdir: JFS:Dtree error: ino = 2, bn=0, index = 7
Oops: general protection fault, probably for non-canonical address 0xdffffc018ad15dbb: 0000 [#1] SMP KASAN PTI
KASAN: probably user-memory-access in range [0x0000000c568aedd8-0x0000000c568aeddf]
CPU: 0 UID: 0 PID: 5798 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:smk_of_inode security/smack/smack.h:409 [inline]
RIP: 0010:smack_inode_permission+0x283/0x330 security/smack/smack_lsm.c:1251
Code: 49 83 c7 38 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 ad 5f ea fd 8b 1d 73 a2 ca 08 49 03 1f 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 8e 5f ea fd 48 8b 3b 44 89 f6 48
RSP: 0018:ffffc90004daf940 EFLAGS: 00010206
RAX: 000000018ad15dbb RBX: 0000000c568aedd8 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc90004daf998
RBP: ffffc90004dafa48 R08: ffffc90004daf9c7 R09: 0000000000000000
R10: ffffc90004daf9a0 R11: fffff520009b5f39 R12: 1ffff920009b5f2c
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880658648b8
FS:  000055558d376500(0000) GS:ffff888126d01000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2a9f9d6000 CR3: 00000000298cc000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 security_inode_permission+0xf8/0x310 security/security.c:1816
 lookup_inode_permission_may_exec fs/namei.c:639 [inline]
 may_lookup fs/namei.c:1900 [inline]
 link_path_walk+0xc2d/0x18d0 fs/namei.c:2537
 path_lookupat+0xe4/0x8c0 fs/namei.c:2745
 filename_lookup+0x212/0x570 fs/namei.c:2775
 user_path_at+0x3a/0x60 fs/namei.c:3567
 ksys_umount fs/namespace.c:2058 [inline]
 __do_sys_umount fs/namespace.c:2066 [inline]
 __se_sys_umount fs/namespace.c:2064 [inline]
 __x64_sys_umount+0xee/0x160 fs/namespace.c:2064
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1aabb20a77
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffdf7c2e958 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 00007f1aabba3d7d RCX: 00007f1aabb20a77
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdf7c2ea10
RBP: 00007ffdf7c2ea10 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdf7c2fb00
R13: 00007f1aabba3d7d R14: 0000000000035150 R15: 00007ffdf7c30bd0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:smk_of_inode security/smack/smack.h:409 [inline]
RIP: 0010:smack_inode_permission+0x283/0x330 security/smack/smack_lsm.c:1251
Code: 49 83 c7 38 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 ad 5f ea fd 8b 1d 73 a2 ca 08 49 03 1f 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 8e 5f ea fd 48 8b 3b 44 89 f6 48
RSP: 0018:ffffc90004daf940 EFLAGS: 00010206
RAX: 000000018ad15dbb RBX: 0000000c568aedd8 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc90004daf998
RBP: ffffc90004dafa48 R08: ffffc90004daf9c7 R09: 0000000000000000
R10: ffffc90004daf9a0 R11: fffff520009b5f39 R12: 1ffff920009b5f2c
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880658648b8
FS:  000055558d376500(0000) GS:ffff888126d01000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2a9f9d6000 CR3: 00000000298cc000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	49 83 c7 38          	add    $0x38,%r15
   4:	4c 89 f8             	mov    %r15,%rax
   7:	48 c1 e8 03          	shr    $0x3,%rax
   b:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1)
  10:	74 08                	je     0x1a
  12:	4c 89 ff             	mov    %r15,%rdi
  15:	e8 ad 5f ea fd       	call   0xfdea5fc7
  1a:	8b 1d 73 a2 ca 08    	mov    0x8caa273(%rip),%ebx        # 0x8caa293
  20:	49 03 1f             	add    (%r15),%rbx
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	48 89 df             	mov    %rbx,%rdi
  34:	e8 8e 5f ea fd       	call   0xfdea5fc7
  39:	48 8b 3b             	mov    (%rbx),%rdi
  3c:	44 89 f6             	mov    %r14d,%esi
  3f:	48                   	rex.W

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/19 18:35 upstream dd9b004b7ff3 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in smack_inode_permission
2025/12/16 01:41 upstream 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in smack_inode_permission
2025/11/19 05:28 upstream 5bebe8de1926 ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in smack_inode_permission
2025/11/03 02:35 upstream 6146a0f1dfae 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in smack_inode_permission
* Struck through repros no longer work on HEAD.