kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 3364 Comm: kmmpd-loop5 Tainted: G        W         5.4.292-syzkaller-00021-gcd8e74fa0fa3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:bdevname+0x30/0xb0 block/partition-generic.c:49
Code: 41 56 41 55 41 54 53 48 89 f3 49 89 ff 49 bd 00 00 00 00 00 fc ff df e8 ae b5 49 ff 49 8d bf 80 00 00 00 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 05 e8 c4 af 77 ff 4d 8b b7 80 00 00 00 49 83 c7
RSP: 0018:ffff8881deecfdd8 EFLAGS: 00010202
RAX: 0000000000000010 RBX: ffff8881cd081050 RCX: ffff8881f37f2f40
RDX: 0000000000000000 RSI: ffff8881cd081050 RDI: 0000000000000080
RBP: ffff8881deecfe00 R08: dffffc0000000000 R09: ffffed103c104611
R10: ffffed103c104611 R11: 1ffff1103c104610 R12: ffff8881df1cddc0
R13: dffffc0000000000 R14: 0000000000000005 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000001e6ac6000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 kmmpd+0x1e6/0x9a0 fs/ext4/mmp.c:158
 kthread+0x31e/0x3a0 kernel/kthread.c:288
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:354
Modules linked in:
---[ end trace 1db9df427189b363 ]---
RIP: 0010:bdevname+0x30/0xb0 block/partition-generic.c:49
Code: 41 56 41 55 41 54 53 48 89 f3 49 89 ff 49 bd 00 00 00 00 00 fc ff df e8 ae b5 49 ff 49 8d bf 80 00 00 00 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 05 e8 c4 af 77 ff 4d 8b b7 80 00 00 00 49 83 c7
RSP: 0018:ffff8881deecfdd8 EFLAGS: 00010202
RAX: 0000000000000010 RBX: ffff8881cd081050 RCX: ffff8881f37f2f40
RDX: 0000000000000000 RSI: ffff8881cd081050 RDI: 0000000000000080
RBP: ffff8881deecfe00 R08: dffffc0000000000 R09: ffffed103c104611
R10: ffffed103c104611 R11: 1ffff1103c104610 R12: ffff8881df1cddc0
R13: dffffc0000000000 R14: 0000000000000005 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555558d654a8 CR3: 00000001e2373000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	41 56                	push   %r14
   2:	41 55                	push   %r13
   4:	41 54                	push   %r12
   6:	53                   	push   %rbx
   7:	48 89 f3             	mov    %rsi,%rbx
   a:	49 89 ff             	mov    %rdi,%r15
   d:	49 bd 00 00 00 00 00 	movabs $0xdffffc0000000000,%r13
  14:	fc ff df
  17:	e8 ae b5 49 ff       	call   0xff49b5ca
  1c:	49 8d bf 80 00 00 00 	lea    0x80(%r15),%rdi
  23:	48 89 f8             	mov    %rdi,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1) <-- trapping instruction
  2f:	74 05                	je     0x36
  31:	e8 c4 af 77 ff       	call   0xff77affa
  36:	4d 8b b7 80 00 00 00 	mov    0x80(%r15),%r14
  3d:	49                   	rex.WB
  3e:	83                   	.byte 0x83
  3f:	c7                   	.byte 0xc7