syzbot


BUG: unable to handle kernel paging request in ext4_ext_map_blocks

Status: upstream: reported C repro on 2026/03/25 11:12
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+3ad17e94107dda6b6b03@syzkaller.appspotmail.com
First crash: 63d, last: 2h26m
Bug presence (2)
Date Name Commit Repro Result
2026/03/26 linux-6.6.y (ToT) c09fbcd31ae6 C [report] BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/03/26 upstream (ToT) 46b513250491 C Didn't crash
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 BUG: unable to handle kernel paging request in ext4_ext_map_blocks 8 C error 1401 46d 63d 0/3 upstream: reported C repro on 2026/03/25 10:41
android-6-1 BUG: unable to handle kernel paging request in ext4_ext_map_blocks origin:lts 8 C 2291 4d08h 31d 0/2 upstream: reported C repro on 2026/04/25 17:59
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2026/05/22 16:23 18m fix candidate upstream error job log
2026/03/28 18:34 1m fix candidate upstream error job log

Sample crash report:
EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!
EXT4-fs error (device loop0): ext4_do_update_inode:5255: inode #3: comm syz.0.17: corrupted inode contents
EXT4-fs error (device loop0): ext4_dirty_inode:6143: inode #3: comm syz.0.17: mark_inode_dirty error
EXT4-fs error (device loop0): ext4_do_update_inode:5255: inode #3: comm syz.0.17: corrupted inode contents
EXT4-fs error (device loop0): __ext4_ext_dirty:206: inode #3: comm syz.0.17: mark_inode_dirty error
BUG: unable to handle page fault for address: ffffffffffffff93
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD cf35067 P4D cf35067 PUD cf37067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 5928 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:ext4_ext_drop_refs fs/ext4/extents.c:119 [inline]
RIP: 0010:ext4_free_ext_path fs/ext4/extents.c:128 [inline]
RIP: 0010:ext4_ext_map_blocks+0x2d11/0x6800 fs/ext4/extents.c:4498
Code: 8b 7c 24 10 4d 85 ff 0f 84 bd 00 00 00 e8 f7 e0 58 ff 49 8d 7f 08 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 0f 85 3d 1e 00 00 <41> 0f b7 47 08 c1 e0 04 48 8d 04 40 48 89 44 24 08 4d 89 fc 49 8d
RSP: 0018:ffffc90003346ae0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffffffffffff8b RCX: ffff888079b09e00
RDX: 0000000000000000 RSI: ffffffff8d2d5670 RDI: ffffffffffffff93
RBP: ffffc90003346d90 R08: ffff888079b09e00 R09: 0000000000000002
R10: 00000000ffffffe4 R11: 0000000000000000 R12: 0000000000000001
R13: 1ffff92000668d88 R14: dffffc0000000000 R15: ffffffffffffff8b
FS:  000055558b7d9500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffff93 CR3: 00000000731e8000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 ext4_map_blocks+0x9e2/0x1b80 fs/ext4/inode.c:654
 ext4_getblk+0x1d0/0x6f0 fs/ext4/inode.c:864
 ext4_bread+0x2a/0x170 fs/ext4/inode.c:920
 ext4_quota_write+0x23a/0x580 fs/ext4/super.c:7317
 write_blk fs/quota/quota_tree.c:70 [inline]
 get_free_dqblk+0x35a/0x710 fs/quota/quota_tree.c:136
 do_insert_tree+0x253/0x10a0 fs/quota/quota_tree.c:347
 do_insert_tree+0xa1a/0x10a0 fs/quota/quota_tree.c:402
 do_insert_tree+0xa1a/0x10a0 fs/quota/quota_tree.c:402
 do_insert_tree+0xa1a/0x10a0 fs/quota/quota_tree.c:402
 dq_insert_tree fs/quota/quota_tree.c:432 [inline]
 qtree_write_dquot+0x4a1/0x5d0 fs/quota/quota_tree.c:451
 v2_write_dquot+0x10c/0x1a0 fs/quota/quota_v2.c:361
 dquot_acquire+0x320/0x610 fs/quota/dquot.c:474
 ext4_acquire_dquot+0x2e3/0x4b0 fs/ext4/super.c:6949
 dqget+0x77c/0xeb0 fs/quota/dquot.c:990
 __dquot_initialize+0x3c7/0xcd0 fs/quota/dquot.c:1518
 ext4_process_orphan+0x54/0x300 fs/ext4/orphan.c:327
 ext4_orphan_cleanup+0xbec/0x1420 fs/ext4/orphan.c:472
 __ext4_fill_super fs/ext4/super.c:5621 [inline]
 ext4_fill_super+0x5eea/0x67b0 fs/ext4/super.c:5744
 get_tree_bdev+0x3f3/0x520 fs/super.c:1591
 vfs_get_tree+0x8c/0x280 fs/super.c:1764
 do_new_mount+0x24b/0xa40 fs/namespace.c:3386
 do_mount fs/namespace.c:3726 [inline]
 __do_sys_mount fs/namespace.c:3935 [inline]
 __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f649dd9e04a
Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffcbd3c96d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffcbd3c9760 RCX: 00007f649dd9e04a
RDX: 0000200000000100 RSI: 0000200000000200 RDI: 00007ffcbd3c9720
RBP: 0000200000000100 R08: 00007ffcbd3c9760 R09: 000000000200000a
R10: 000000000200000a R11: 0000000000000246 R12: 0000200000000200
R13: 00007ffcbd3c9720 R14: 000000000000051a R15: 0000200000000240
 </TASK>
Modules linked in:
CR2: ffffffffffffff93
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_ext_drop_refs fs/ext4/extents.c:119 [inline]
RIP: 0010:ext4_free_ext_path fs/ext4/extents.c:128 [inline]
RIP: 0010:ext4_ext_map_blocks+0x2d11/0x6800 fs/ext4/extents.c:4498
Code: 8b 7c 24 10 4d 85 ff 0f 84 bd 00 00 00 e8 f7 e0 58 ff 49 8d 7f 08 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 0f 85 3d 1e 00 00 <41> 0f b7 47 08 c1 e0 04 48 8d 04 40 48 89 44 24 08 4d 89 fc 49 8d
RSP: 0018:ffffc90003346ae0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffffffffffff8b RCX: ffff888079b09e00
RDX: 0000000000000000 RSI: ffffffff8d2d5670 RDI: ffffffffffffff93
RBP: ffffc90003346d90 R08: ffff888079b09e00 R09: 0000000000000002
R10: 00000000ffffffe4 R11: 0000000000000000 R12: 0000000000000001
R13: 1ffff92000668d88 R14: dffffc0000000000 R15: ffffffffffffff8b
FS:  000055558b7d9500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffff93 CR3: 00000000731e8000 CR4: 00000000003506f0
----------------
Code disassembly (best guess):
   0:	8b 7c 24 10          	mov    0x10(%rsp),%edi
   4:	4d 85 ff             	test   %r15,%r15
   7:	0f 84 bd 00 00 00    	je     0xca
   d:	e8 f7 e0 58 ff       	call   0xff58e109
  12:	49 8d 7f 08          	lea    0x8(%r15),%rdi
  16:	48 89 f8             	mov    %rdi,%rax
  19:	48 c1 e8 03          	shr    $0x3,%rax
  1d:	42 0f b6 04 30       	movzbl (%rax,%r14,1),%eax
  22:	84 c0                	test   %al,%al
  24:	0f 85 3d 1e 00 00    	jne    0x1e67
* 2a:	41 0f b7 47 08       	movzwl 0x8(%r15),%eax <-- trapping instruction
  2f:	c1 e0 04             	shl    $0x4,%eax
  32:	48 8d 04 40          	lea    (%rax,%rax,2),%rax
  36:	48 89 44 24 08       	mov    %rax,0x8(%rsp)
  3b:	4d 89 fc             	mov    %r15,%r12
  3e:	49                   	rex.WB
  3f:	8d                   	.byte 0x8d

Crashes (3160):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/11 05:54 linux-6.6.y 3b9f64db0496 29233ece .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/10 06:54 linux-6.6.y 3b9f64db0496 29233ece .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/04/06 06:13 linux-6.6.y c09fbcd31ae6 4440e7c2 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/04/05 10:22 linux-6.6.y c09fbcd31ae6 4440e7c2 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/03/26 09:03 linux-6.6.y c09fbcd31ae6 c6143aac .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/03/26 09:56 linux-6.6.y c09fbcd31ae6 c6143aac .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-6-kasan general protection fault in ext4_ext_map_blocks
2026/05/27 09:57 linux-6.6.y 0a40c6fbd105 2b01f00e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/27 08:17 linux-6.6.y 0a40c6fbd105 2b01f00e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/27 06:02 linux-6.6.y 0a40c6fbd105 2b01f00e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/27 05:52 linux-6.6.y 0a40c6fbd105 2b01f00e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/27 04:25 linux-6.6.y 0a40c6fbd105 2b01f00e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/27 00:32 linux-6.6.y 0a40c6fbd105 2b01f00e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/26 20:32 linux-6.6.y 0a40c6fbd105 a3e47276 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/26 20:29 linux-6.6.y 0a40c6fbd105 a3e47276 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/26 18:31 linux-6.6.y 0a40c6fbd105 a3e47276 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/26 02:21 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/25 21:36 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/25 20:04 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/25 19:29 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/25 15:44 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/25 13:49 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/25 12:26 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/25 03:44 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/25 03:07 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/25 01:06 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/25 00:29 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/24 23:05 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/24 16:37 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/24 16:21 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/24 11:52 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/24 05:06 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/24 03:43 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/24 02:06 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/23 23:03 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/23 23:02 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/23 20:08 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/23 18:32 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/23 13:44 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/23 10:39 linux-6.6.y eac8889a3a1c c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/23 07:57 linux-6.6.y eac8889a3a1c c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/23 03:02 linux-6.6.y eac8889a3a1c c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/22 21:03 linux-6.6.y eac8889a3a1c 5f091fcc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/22 20:39 linux-6.6.y eac8889a3a1c 5f091fcc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/03/25 11:11 linux-6.6.y c09fbcd31ae6 8ee77f7d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan BUG: unable to handle kernel paging request in ext4_ext_map_blocks
2026/05/26 23:22 linux-6.6.y 0a40c6fbd105 2b01f00e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in ext4_ext_map_blocks
2026/05/26 16:35 linux-6.6.y 0a40c6fbd105 a3e47276 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in ext4_ext_map_blocks
2026/05/26 14:40 linux-6.6.y 0a40c6fbd105 a3e47276 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in ext4_ext_map_blocks
2026/05/24 15:06 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in ext4_ext_map_blocks
2026/05/24 08:44 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in ext4_ext_map_blocks
2026/05/24 07:34 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in ext4_ext_map_blocks
* Struck through repros no longer work on HEAD.