syzbot


general protection fault in xa_destroy

Status: moderation: reported on 2025/08/05 06:03
Subsystems: ext4
[Documentation on labels]
Reported-by: syzbot+75523e41ed02eff3e3a7@syzkaller.appspotmail.com
First crash: 21d, last: 3d01h

Sample crash report:
loop0: detected capacity change from 0 to 128
__kmem_cache_create_args(ext4_groupinfo_1k) failed with error -22
CPU: 0 UID: 0 PID: 5352 Comm: syz.0.0 Not tainted 6.17.0-rc2-syzkaller-00028-gbe48bcf004f9 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 __kmem_cache_create_args+0x237/0x320 mm/slab_common.c:353
 __kmem_cache_create include/linux/slab.h:353 [inline]
 ext4_groupinfo_create_slab fs/ext4/mballoc.c:3590 [inline]
 ext4_mb_init+0x2ff/0x2860 fs/ext4/mballoc.c:3693
 __ext4_fill_super fs/ext4/super.c:5558 [inline]
 ext4_fill_super+0x5253/0x6090 fs/ext4/super.c:5728
 get_tree_bdev_flags+0x40b/0x4d0 fs/super.c:1692
 vfs_get_tree+0x92/0x2b0 fs/super.c:1815
 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
 do_mount fs/namespace.c:4133 [inline]
 __do_sys_mount fs/namespace.c:4344 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4321
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f79a579038a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f79a656ee68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f79a656eef0 RCX: 00007f79a579038a
RDX: 0000200000000200 RSI: 0000200000000740 RDI: 00007f79a656eeb0
RBP: 0000200000000200 R08: 00007f79a656eef0 R09: 000000000000c000
R10: 000000000000c000 R11: 0000000000000246 R12: 0000200000000740
R13: 00007f79a656eeb0 R14: 0000000000000246 R15: 00002000000006c0
 </TASK>
EXT4-fs: no memory for groupinfo slab cache
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 UID: 0 PID: 5352 Comm: syz.0.0 Not tainted 6.17.0-rc2-syzkaller-00028-gbe48bcf004f9 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline]
RIP: 0010:do_raw_spin_lock+0x78/0x290 kernel/locking/spinlock_debug.c:115
Code: fe 9d 81 48 8d 4c 24 20 48 c1 e9 03 48 b8 f1 f1 f1 f1 04 f3 f3 f3 48 89 4c 24 18 4a 89 04 39 4c 8d 77 04 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 9f 01 00 00 41 8b 06 3d ad 4e ad de 0f
RSP: 0018:ffffc9000d26f700 EFLAGS: 00010047
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffff92001a4dee4
RDX: 0000000000000000 RSI: ffffffff8be348e0 RDI: 0000000000000000
RBP: ffffc9000d26f7b0 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f47487 R12: dffffc0000000000
R13: ffff888043d12560 R14: 0000000000000004 R15: dffffc0000000000
FS:  00007f79a656f6c0(0000) GS:ffff88808d210000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555ae74e9970 CR3: 000000003e40e000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
 _raw_spin_lock_irqsave+0xb3/0xf0 kernel/locking/spinlock.c:162
 xa_destroy+0x59/0x2e0 lib/xarray.c:2390
 ext4_mb_avg_fragment_size_destroy fs/ext4/mballoc.c:3659 [inline]
 ext4_mb_init+0x136a/0x2860 fs/ext4/mballoc.c:3817
 __ext4_fill_super fs/ext4/super.c:5558 [inline]
 ext4_fill_super+0x5253/0x6090 fs/ext4/super.c:5728
 get_tree_bdev_flags+0x40b/0x4d0 fs/super.c:1692
 vfs_get_tree+0x92/0x2b0 fs/super.c:1815
 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
 do_mount fs/namespace.c:4133 [inline]
 __do_sys_mount fs/namespace.c:4344 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4321
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f79a579038a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f79a656ee68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f79a656eef0 RCX: 00007f79a579038a
RDX: 0000200000000200 RSI: 0000200000000740 RDI: 00007f79a656eeb0
RBP: 0000200000000200 R08: 00007f79a656eef0 R09: 000000000000c000
R10: 000000000000c000 R11: 0000000000000246 R12: 0000200000000740
R13: 00007f79a656eeb0 R14: 0000000000000246 R15: 00002000000006c0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline]
RIP: 0010:do_raw_spin_lock+0x78/0x290 kernel/locking/spinlock_debug.c:115
Code: fe 9d 81 48 8d 4c 24 20 48 c1 e9 03 48 b8 f1 f1 f1 f1 04 f3 f3 f3 48 89 4c 24 18 4a 89 04 39 4c 8d 77 04 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 9f 01 00 00 41 8b 06 3d ad 4e ad de 0f
RSP: 0018:ffffc9000d26f700 EFLAGS: 00010047
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffff92001a4dee4
RDX: 0000000000000000 RSI: ffffffff8be348e0 RDI: 0000000000000000
RBP: ffffc9000d26f7b0 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f47487 R12: dffffc0000000000
R13: ffff888043d12560 R14: 0000000000000004 R15: dffffc0000000000
FS:  00007f79a656f6c0(0000) GS:ffff88808d210000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555ae74e9970 CR3: 000000003e40e000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	9d                   	popf
   1:	81 48 8d 4c 24 20 48 	orl    $0x4820244c,-0x73(%rax)
   8:	c1 e9 03             	shr    $0x3,%ecx
   b:	48 b8 f1 f1 f1 f1 04 	movabs $0xf3f3f304f1f1f1f1,%rax
  12:	f3 f3 f3
  15:	48 89 4c 24 18       	mov    %rcx,0x18(%rsp)
  1a:	4a 89 04 39          	mov    %rax,(%rcx,%r15,1)
  1e:	4c 8d 77 04          	lea    0x4(%rdi),%r14
  22:	4c 89 f0             	mov    %r14,%rax
  25:	48 c1 e8 03          	shr    $0x3,%rax
* 29:	42 0f b6 04 38       	movzbl (%rax,%r15,1),%eax <-- trapping instruction
  2e:	84 c0                	test   %al,%al
  30:	0f 85 9f 01 00 00    	jne    0x1d5
  36:	41 8b 06             	mov    (%r14),%eax
  39:	3d ad 4e ad de       	cmp    $0xdead4ead,%eax
  3e:	0f                   	.byte 0xf

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/19 15:00 upstream be48bcf004f9 523f460e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in xa_destroy
2025/08/18 08:07 upstream 8d561baae505 dcc075fb .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in xa_destroy
2025/08/18 00:37 upstream 8d561baae505 dcc075fb .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in xa_destroy
2025/08/01 05:52 upstream d6084bb815c4 0c075d67 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in xa_destroy
* Struck through repros no longer work on HEAD.