syzbot


BUG: unable to handle kernel paging request in dbUpdatePMap

Status: upstream: reported C repro on 2025/11/22 04:56
Reported-by: syzbot+8b9738aed3fee77451a0@syzkaller.appspotmail.com
First crash: 2d17h, last: 7h10m
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: corrupted list in dbUpdatePMap jfs 8 C error 7 2d07h 18d 0/29 upstream: reported C repro on 2025/11/06 00:09
linux-4.19 general protection fault in dbUpdatePMap 2 C error 2 1126d 1126d 0/1 upstream: reported C repro on 2022/10/25 14:29
linux-6.6 general protection fault in dbUpdatePMap 2 C 1 16h41m 16h41m 0/2 upstream: reported C repro on 2025/11/24 06:07

Sample crash report:
Unable to handle kernel paging request at virtual address fbd5200000000021
KASAN: maybe wild-memory-access in range [0xdead000000000108-0xdead00000000010f]
Mem abort info:
  ESR = 0x0000000096000004
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x04: level 0 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000004
  CM = 0, WnR = 0
[fbd5200000000021] address between user and kernel address ranges
Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 92 Comm: jfsCommit Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
pstate: 824000c5 (Nzcv daIF +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : __list_add_valid+0x3c/0x110 lib/list_debug.c:27
lr : __list_add include/linux/list.h:69 [inline]
lr : list_add include/linux/list.h:88 [inline]
lr : dbUpdatePMap+0x5f0/0xc40 fs/jfs/jfs_dmap.c:577
sp : ffff80001ce97ac0
x29: ffff80001ce97ac0 x28: 0000000000000004 x27: ffff0000c983a1f0
x26: dfff800000000000 x25: 0000000000000004 x24: dead000000000100
x23: dfff800000000000 x22: dead000000000108 x21: ffff0000c983a200
x20: ffff80001fd29120 x19: dead000000000100 x18: ffff800011abbcc0
x17: 1fffe00033edbb7e x16: ffff8000082e7914 x15: ffff8000150bd000
x14: 0000000000000100 x13: 1ffff00002a180b1 x12: 0000000000ff0100
x11: ff0080000986e11c x10: ffff0000d5053a80 x9 : 0000000000000000
x8 : 1bd5a00000000021 x7 : ffff80000986e0e8 x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : ffff8000082e7a34
x2 : dead000000000100 x1 : ffff80001fd29120 x0 : ffff0000c983a200
Call trace:
 __list_add_valid+0x3c/0x110 lib/list_debug.c:27
 __list_add include/linux/list.h:69 [inline]
 list_add include/linux/list.h:88 [inline]
 dbUpdatePMap+0x5f0/0xc40 fs/jfs/jfs_dmap.c:577
 txAllocPMap+0x4a0/0x5d4 fs/jfs/jfs_txnmgr.c:2425
 txUpdateMap+0x628/0x79c fs/jfs/jfs_txnmgr.c:2363
 txLazyCommit fs/jfs/jfs_txnmgr.c:2664 [inline]
 jfs_lazycommit+0x378/0x918 fs/jfs/jfs_txnmgr.c:2732
 kthread+0x250/0x2d8 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850
Code: aa0103f4 d343fec8 f2fbfff7 aa0003f5 (38776908) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	aa0103f4 	mov	x20, x1
   4:	d343fec8 	lsr	x8, x22, #3
   8:	f2fbfff7 	movk	x23, #0xdfff, lsl #48
   c:	aa0003f5 	mov	x21, x0
* 10:	38776908 	ldrb	w8, [x8, x23] <-- trapping instruction

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/22 06:33 linux-6.1.y f6e38ae624cf 4fb8ef37 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 BUG: unable to handle kernel paging request in dbUpdatePMap
2025/11/23 21:21 linux-6.1.y f6e38ae624cf 4fb8ef37 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan general protection fault in dbUpdatePMap
2025/11/22 04:55 linux-6.1.y f6e38ae624cf 4fb8ef37 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 BUG: unable to handle kernel paging request in dbUpdatePMap
2025/11/24 15:39 linux-6.1.y f6e38ae624cf bf6fe8fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan BUG: corrupted list in dbUpdatePMap
* Struck through repros no longer work on HEAD.