[syzbot] [mm?] general protection fault in lru_gen_test_recent (2)

syzbot
2025-12-07T08:55:26Z

Hello,

syzbot found the following issue on:

HEAD commit: c06c303832ec ocfs2: fix xattr array entry __counted_by error
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14cbfc1a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=5aef7d5187304591
dashboard link: https://syzkaller.appspot.com/bug?extid=e008db2ac01e282550ee
compiler: gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=127f2992580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15cf4eb4580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-c06c3038.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1a5115eeda38/vmlinux-c06c3038.xz
kernel image: https://storage.googleapis.com/syzbot-assets/98eb17e54bb8/bzImage-c06c3038.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e008db2ac01e282550ee@syzkaller.appspotmail.com

Oops: general protection fault, probably for non-canonical address 0xdffffc00000009c0: 0000 [#1] SMP KASAN NOPTI
KASAN: probably user-memory-access in range [0x0000000000004e00-0x0000000000004e07]
CPU: 2 UID: 0 PID: 6121 Comm: syz.0.27 Not tainted syzkaller #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:mem_cgroup_lruvec include/linux/memcontrol.h:720 [inline]
RIP: 0010:lru_gen_test_recent+0xee/0x320 mm/workingset.c:275
Code: 38 80 b5 ff 48 85 db 0f 84 79 01 00 00 e8 2a 80 b5 ff 49 8d bd 00 4e 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e a3 01 00 00 4d 63 b5 00 4e 00
RSP: 0018:ffffc90003e17828 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffff888100068000 RCX: ffffc90003e1772c
RDX: 00000000000009c0 RSI: ffffffff82096446 RDI: 0000000000004e00
RBP: ffffc90003e178c0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffff888028282ff0 R12: ffffc90003e178e0
R13: 0000000000000000 R14: ffffc90003e178b0 R15: 0000000000000000
FS: 00007f6361dfa6c0(0000) GS:ffff8880d6b0d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000409000000 CR3: 0000000039516000 CR4: 0000000000352ef0
Call Trace:
<TASK>
lru_gen_refault mm/workingset.c:296 [inline]
workingset_refault+0x251/0xca0 mm/workingset.c:546
filemap_add_folio+0x23d/0x610 mm/filemap.c:981
do_read_cache_folio+0x23c/0x5c0 mm/filemap.c:4063
freader_get_folio+0x33a/0x930 lib/buildid.c:58
freader_fetch+0xbd/0x740 lib/buildid.c:101
__build_id_parse.isra.0+0xdd/0x6c0 lib/buildid.c:289
do_procmap_query+0xb0e/0x1080 fs/proc/task_mmu.c:733
procfs_procmap_ioctl+0x9d/0xe0 fs/proc/task_mmu.c:813
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6360f8f7c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6361dfa038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f63611e5fa0 RCX: 00007f6360f8f7c9
RDX: 0000200000000180 RSI: 00000000c0686611 RDI: 0000000000000003
RBP: 00007f6361013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f63611e6038 R14: 00007f63611e5fa0 R15: 00007ffe36ff8138
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:mem_cgroup_lruvec include/linux/memcontrol.h:720 [inline]
RIP: 0010:lru_gen_test_recent+0xee/0x320 mm/workingset.c:275
Code: 38 80 b5 ff 48 85 db 0f 84 79 01 00 00 e8 2a 80 b5 ff 49 8d bd 00 4e 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e a3 01 00 00 4d 63 b5 00 4e 00
RSP: 0018:ffffc90003e17828 EFLAGS: 00010206

RAX: dffffc0000000000 RBX: ffff888100068000 RCX: ffffc90003e1772c
RDX: 00000000000009c0 RSI: ffffffff82096446 RDI: 0000000000004e00
RBP: ffffc90003e178c0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffff888028282ff0 R12: ffffc90003e178e0
R13: 0000000000000000 R14: ffffc90003e178b0 R15: 0000000000000000
FS: 00007f6361dfa6c0(0000) GS:ffff8880d6b0d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000409000000 CR3: 0000000039516000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess):
0: 38 80 b5 ff 48 85 cmp %al,-0x7ab7004b(%rax)
6: db 0f fisttpl (%rdi)
8: 84 79 01 test %bh,0x1(%rcx)
b: 00 00 add %al,(%rax)
d: e8 2a 80 b5 ff call 0xffb5803c
12: 49 8d bd 00 4e 00 00 lea 0x4e00(%r13),%rdi
19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
20: fc ff df
23: 48 89 fa mov %rdi,%rdx
26: 48 c1 ea 03 shr $0x3,%rdx
* 2a: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax <-- trapping instruction
2e: 84 c0 test %al,%al
30: 74 08 je 0x3a
32: 3c 03 cmp $0x3,%al
34: 0f 8e a3 01 00 00 jle 0x1dd
3a: 4d rex.WRB
3b: 63 .byte 0x63
3c: b5 00 mov $0x0,%ch
3e: 4e rex.WRX

---
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