syzbot


general protection fault in __rt_mutex_slowlock_locked

Status: upstream: reported on 2025/11/11 20:25
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+60f8f8d9d0a992e59f1a@syzkaller.appspotmail.com
First crash: 131d, last: 2d21h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [mm?] general protection fault in __rt_mutex_slowlock_locked 0 (1) 2025/11/11 20:25

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc00e000015e: 0000 [#1] SMP KASAN PTI
KASAN: probably user-memory-access in range [0x0000000700000af0-0x0000000700000af7]
CPU: 1 UID: 0 PID: 9891 Comm: syz.2.532 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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 e9 00 20 fc 08 cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc90006db71d8 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: ffffffff8b26544e RCX: 0000000080000003
RDX: 0000000000000000 RSI: ffffffff8b26544e RDI: 00000000e000015e
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1005c29ccc R12: 0000000000000000
R13: 0000000700000af0 R14: 0000000700000af0 R15: 0000000000000001
FS:  00007fb7aaf466c0(0000) GS:ffff88812643c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb7a2b0c000 CR3: 000000003cef4000 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+0x79/0x2e0 kernel/locking/lockdep.c:5842
 __raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 task_blocks_on_rt_mutex kernel/locking/rtmutex.c:1265 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1719 [inline]
 __rt_mutex_slowlock_locked+0x1226/0x25c0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244
 i_mmap_lock_write include/linux/fs.h:512 [inline]
 vma_link_file mm/vma.c:1817 [inline]
 __mmap_new_vma mm/vma.c:2555 [inline]
 __mmap_region mm/vma.c:2759 [inline]
 mmap_region+0x1ce2/0x2230 mm/vma.c:2837
 do_mmap+0xc2f/0x10c0 mm/mmap.c:559
 vm_mmap_pgoff+0x2cc/0x4f0 mm/util.c:581
 ksys_mmap_pgoff+0x4e8/0x720 mm/mmap.c:605
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb7accec799
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:00007fb7aaf46028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007fb7acf65fa0 RCX: 00007fb7accec799
RDX: 0000000000000001 RSI: 0000000000400000 RDI: 0000200000000000
RBP: 00007fb7acd82c99 R08: 0000000000000006 R09: 0000000000000000
R10: 0000000000010012 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb7acf66038 R14: 00007fb7acf65fa0 R15: 00007fffb4aa89c8
 </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> b6 04 07 3c 08 0f 92 c0 e9 00 20 fc 08 cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc90006db71d8 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: ffffffff8b26544e RCX: 0000000080000003
RDX: 0000000000000000 RSI: ffffffff8b26544e RDI: 00000000e000015e
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1005c29ccc R12: 0000000000000000
R13: 0000000700000af0 R14: 0000000700000af0 R15: 0000000000000001
FS:  00007fb7aaf466c0(0000) GS:ffff88812643c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb7a2b0c000 CR3: 000000003cef4000 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:	e9 00 20 fc 08       	jmp    0x8fc2034
  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 (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/16 12:17 upstream f338e7738378 64e21424 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in __rt_mutex_slowlock_locked
2026/02/25 07:04 upstream 7dff99b35460 787dfb7c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in __rt_mutex_slowlock_locked
2026/02/21 03:02 upstream a95f71ad3e2e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in __rt_mutex_slowlock_locked
2026/02/20 03:27 upstream 8bf22c33e7a1 c8d8c52d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in __rt_mutex_slowlock_locked
2026/02/16 12:34 upstream c22e26bd0906 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in __rt_mutex_slowlock_locked
2026/02/16 03:15 upstream c22e26bd0906 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in __rt_mutex_slowlock_locked
2026/01/06 19:22 upstream f0b9d8eb98df d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in __rt_mutex_slowlock_locked
2026/01/01 11:37 upstream b69053dd3ffb d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in __rt_mutex_slowlock_locked
2025/12/27 01:11 upstream 3f0e9c8cefa9 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in __rt_mutex_slowlock_locked
2025/11/07 18:47 upstream 4a0c9b339199 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in __rt_mutex_slowlock_locked
2025/11/07 18:46 upstream 4a0c9b339199 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in __rt_mutex_slowlock_locked
* Struck through repros no longer work on HEAD.