[syzbot] [mm?] general protection fault in find_lock_task_mm

[syzbot <syzbot+c2e074db555379260750@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    231825b2e1ff Revert "unicode: Don't special case ignorable..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=133b4d44580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=99a5586995ec03b2
dashboard link: https://syzkaller.appspot.com/bug?extid=c2e074db555379260750
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=102844f8580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/41e68d86d902/disk-231825b2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0cb4e353f885/vmlinux-231825b2.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c4df524e0176/bzImage-231825b2.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c2e074db555379260750@syzkaller.appspotmail.com

Oops: general protection fault, probably for non-canonical address 0xdffffc000000006c: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000360-0x0000000000000367]
CPU: 0 UID: 0 PID: 8122 Comm: syz-executor Not tainted 6.13.0-rc2-syzkaller-00036-g231825b2e1ff #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
RIP: 0010:__lock_acquire+0xe4/0x3c40 kernel/locking/lockdep.c:5089
Code: 08 84 d2 0f 85 15 14 00 00 44 8b 0d 4a 00 a7 0e 45 85 c9 0f 84 b4 0e 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 0f 85 96 2c 00 00 49 8b 04 24 48 3d a0 17 32 93 0f 84
RSP: 0018:ffffc9000d087990 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 000000000000006c RSI: 1ffff92001a10f44 RDI: 0000000000000360
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff901cc317 R11: 0000000000000002 R12: 0000000000000360
R13: ffff888034c38000 R14: 0000000000000000 R15: 0000000000000000
FS:  00005555879c4500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555879c4808 CR3: 0000000030ed6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 task_lock include/linux/sched/task.h:229 [inline]
 find_lock_task_mm+0xd4/0x2f0 mm/oom_kill.c:140
 __set_oom_adj.isra.0+0xcd8/0x1120 fs/proc/base.c:1157
 oom_score_adj_write+0x1b8/0x200 fs/proc/base.c:1294
 vfs_write+0x24c/0x1150 fs/read_write.c:677
 ksys_write+0x12b/0x250 fs/read_write.c:731
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3c079847cf
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007fffc0defcf0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f3c079847cf
RDX: 0000000000000004 RSI: 00007fffc0defd40 RDI: 0000000000000003
RBP: 00007f3c07a0320c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000004
R13: 00007fffc0defd40 R14: 00007fffc0df02a0 R15: 00007fffc0df02a0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__lock_acquire+0xe4/0x3c40 kernel/locking/lockdep.c:5089
Code: 08 84 d2 0f 85 15 14 00 00 44 8b 0d 4a 00 a7 0e 45 85 c9 0f 84 b4 0e 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 0f 85 96 2c 00 00 49 8b 04 24 48 3d a0 17 32 93 0f 84
RSP: 0018:ffffc9000d087990 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 000000000000006c RSI: 1ffff92001a10f44 RDI: 0000000000000360
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff901cc317 R11: 0000000000000002 R12: 0000000000000360
R13: ffff888034c38000 R14: 0000000000000000 R15: 0000000000000000
FS:  00005555879c4500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555879c4808 CR3: 0000000030ed6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	08 84 d2 0f 85 15 14 	or     %al,0x1415850f(%rdx,%rdx,8)
   7:	00 00                	add    %al,(%rax)
   9:	44 8b 0d 4a 00 a7 0e 	mov    0xea7004a(%rip),%r9d        # 0xea7005a
  10:	45 85 c9             	test   %r9d,%r9d
  13:	0f 84 b4 0e 00 00    	je     0xecd
  19:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  20:	fc ff df
  23:	4c 89 e2             	mov    %r12,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 96 2c 00 00    	jne    0x2cca
  34:	49 8b 04 24          	mov    (%r12),%rax
  38:	48 3d a0 17 32 93    	cmp    $0xffffffff933217a0,%rax
  3e:	0f                   	.byte 0xf
  3f:	84                   	.byte 0x84


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