* [syzbot ci] Re: ext4: fix unaligned preallocation with bigalloc
[not found] <20251122024555.140798-2-eraykrdg1@gmail.com>
@ 2025-11-22 8:55 ` syzbot ci
0 siblings, 0 replies; 2+ messages in thread
From: syzbot ci @ 2025-11-22 8:55 UTC (permalink / raw)
To: adilger.kernel, albinbabuvarghese20, david.hunter.linux,
eraykrdg1, linux-ext4, linux-kernel, skhan, syzbot, tytso
Cc: syzbot, syzkaller-bugs
syzbot ci has tested the following series
[v2] ext4: fix unaligned preallocation with bigalloc
https://lore.kernel.org/all/20251122024555.140798-2-eraykrdg1@gmail.com
* [PATCH v2] ext4: fix unaligned preallocation with bigalloc
and found the following issues:
* WARNING in ext4_mb_complex_scan_group
* WARNING in mb_update_avg_fragment_size
Full report is available here:
https://ci.syzbot.org/series/ba644d0c-b0cd-47e5-aac4-5bc33f8d2823
***
WARNING in ext4_mb_complex_scan_group
tree: torvalds
URL: https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux
base: 23cb64fb76257309e396ea4cec8396d4a1dbae68
arch: amd64
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
config: https://ci.syzbot.org/builds/3d0f1523-91b4-4aa0-b4ec-0f13803a4e4e/config
C repro: https://ci.syzbot.org/findings/d24ca945-6ee1-4b64-827e-93a61ab96735/c_repro
syz repro: https://ci.syzbot.org/findings/d24ca945-6ee1-4b64-827e-93a61ab96735/syz_repro
EXT4-fs: Ignoring removed bh option
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
------------[ cut here ]------------
WARNING: CPU: 1 PID: 5962 at fs/ext4/mballoc.c:2531 ext4_mb_complex_scan_group+0xd64/0xf30 fs/ext4/mballoc.c:2531
Modules linked in:
CPU: 1 UID: 0 PID: 5962 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:ext4_mb_complex_scan_group+0xd64/0xf30 fs/ext4/mballoc.c:2531
Code: 81 c4 c8 00 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d e9 01 f8 cc 08 cc e8 1b 97 43 ff 90 0f 0b 90 e9 3d fe ff ff e8 0d 97 43 ff 90 <0f> 0b 65 48 8b 05 62 e3 f1 0f 48 3b 84 24 c0 00 00 00 75 20 90 eb
RSP: 0018:ffffc90003c069c8 EFLAGS: 00010293
RAX: ffffffff827c6cb3 RBX: 00000000fffffff8 RCX: ffff888114d61d00
RDX: 0000000000000000 RSI: 00000000fffffff8 RDI: 0000000000000001
RBP: ffff88816ef5b000 R08: ffff888114d61d00 R09: 0000000000000005
R10: 0000000000000004 R11: 0000000000000000 R12: ffff888166fec000
R13: ffff888166fec638 R14: ffff8881b7ac0000 R15: dffffc0000000000
FS: 0000555585e78500(0000) GS:ffff8882a9f3b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ec63fff CR3: 000000011407a000 CR4: 00000000000006f0
Call Trace:
<TASK>
__ext4_mb_scan_group fs/ext4/mballoc.c:2664 [inline]
ext4_mb_scan_group+0x116e/0x18e0 fs/ext4/mballoc.c:2955
ext4_mb_scan_groups_linear+0xe8/0x360 fs/ext4/mballoc.c:1146
ext4_mb_scan_groups fs/ext4/mballoc.c:1180 [inline]
ext4_mb_regular_allocator+0x90e/0x2970 fs/ext4/mballoc.c:3026
ext4_mb_new_blocks+0xd11/0x4720 fs/ext4/mballoc.c:6320
ext4_ext_map_blocks+0x161a/0x6ac0 fs/ext4/extents.c:4383
ext4_map_create_blocks fs/ext4/inode.c:609 [inline]
ext4_map_blocks+0x860/0x1740 fs/ext4/inode.c:811
_ext4_get_block+0x200/0x4c0 fs/ext4/inode.c:910
ext4_get_block_unwritten+0x2e/0x100 fs/ext4/inode.c:943
ext4_block_write_begin+0x993/0x1710 fs/ext4/inode.c:1198
ext4_write_begin+0xc04/0x19a0 fs/ext4/ext4_jbd2.h:-1
ext4_da_write_begin+0x445/0xda0 fs/ext4/inode.c:3129
generic_perform_write+0x2c5/0x900 mm/filemap.c:4254
ext4_buffered_write_iter+0xce/0x3a0 fs/ext4/file.c:299
ext4_file_write_iter+0x298/0x1bc0 fs/ext4/file.c:-1
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x5c9/0xb30 fs/read_write.c:686
ksys_write+0x145/0x250 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3f93f8f749
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:00007fff83277a88 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f3f941e5fa0 RCX: 00007f3f93f8f749
RDX: 0000000000001006 RSI: 0000200000000940 RDI: 0000000000000005
RBP: 00007f3f94013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3f941e5fa0 R14: 00007f3f941e5fa0 R15: 0000000000000003
</TASK>
***
WARNING in mb_update_avg_fragment_size
tree: torvalds
URL: https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux
base: 23cb64fb76257309e396ea4cec8396d4a1dbae68
arch: amd64
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
config: https://ci.syzbot.org/builds/3d0f1523-91b4-4aa0-b4ec-0f13803a4e4e/config
C repro: https://ci.syzbot.org/findings/4f77b4c9-f795-4c41-ad77-5c5a174be3a1/c_repro
syz repro: https://ci.syzbot.org/findings/4f77b4c9-f795-4c41-ad77-5c5a174be3a1/syz_repro
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
EXT4-fs: Ignoring removed orlov option
EXT4-fs (loop0): can't enable nombcache during remount
------------[ cut here ]------------
WARNING: CPU: 1 PID: 5969 at fs/ext4/mballoc.c:839 mb_avg_fragment_size_order fs/ext4/mballoc.c:839 [inline]
WARNING: CPU: 1 PID: 5969 at fs/ext4/mballoc.c:839 mb_update_avg_fragment_size+0x304/0x450 fs/ext4/mballoc.c:856
Modules linked in:
CPU: 1 UID: 0 PID: 5969 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:mb_avg_fragment_size_order fs/ext4/mballoc.c:839 [inline]
RIP: 0010:mb_update_avg_fragment_size+0x304/0x450 fs/ext4/mballoc.c:856
Code: 5d 41 5e 41 5f 5d e9 1b 6a cd 08 e8 96 57 44 ff 48 83 c4 28 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 7d 57 44 ff 90 <0f> 0b 90 48 bb 00 00 00 00 00 fc ff df 41 0f b6 44 1d 00 84 c0 0f
RSP: 0018:ffffc90003a56f48 EFLAGS: 00010293
RAX: ffffffff827bac43 RBX: 000000000000000d RCX: ffff8881037ad700
RDX: 0000000000000000 RSI: 000000000000000c RDI: 000000000000001e
RBP: 000000000000001e R08: ffff8881a9014007 R09: 1ffff11035202800
R10: dffffc0000000000 R11: ffffed1035202801 R12: ffff88810b77e014
R13: 1ffff110216efc02 R14: 000000000000001f R15: 000000000000000c
FS: 000055557ed08500(0000) GS:ffff8882a9f3b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9c75c3f000 CR3: 0000000112a5a000 CR4: 00000000000006f0
Call Trace:
<TASK>
mb_mark_used+0xfd8/0x12f0 fs/ext4/mballoc.c:2195
ext4_mb_use_best_found+0x192/0x7e0 fs/ext4/mballoc.c:2216
ext4_mb_check_limits fs/ext4/mballoc.c:2280 [inline]
ext4_mb_complex_scan_group+0xd27/0xf30 fs/ext4/mballoc.c:2596
__ext4_mb_scan_group fs/ext4/mballoc.c:2664 [inline]
ext4_mb_scan_group+0x116e/0x18e0 fs/ext4/mballoc.c:2955
ext4_mb_scan_groups_linear+0xe8/0x360 fs/ext4/mballoc.c:1146
ext4_mb_scan_groups fs/ext4/mballoc.c:1180 [inline]
ext4_mb_regular_allocator+0x90e/0x2970 fs/ext4/mballoc.c:3026
ext4_mb_new_blocks+0xd11/0x4720 fs/ext4/mballoc.c:6320
ext4_ext_map_blocks+0x161a/0x6ac0 fs/ext4/extents.c:4383
ext4_map_create_blocks fs/ext4/inode.c:609 [inline]
ext4_map_blocks+0x860/0x1740 fs/ext4/inode.c:811
ext4_convert_inline_data_nolock+0x249/0x970 fs/ext4/inline.c:1112
ext4_convert_inline_data+0x4b3/0x5e0 fs/ext4/inline.c:1976
ext4_fallocate+0x1e2/0x3d0 fs/ext4/extents.c:4793
vfs_fallocate+0x669/0x7e0 fs/open.c:342
ksys_fallocate fs/open.c:366 [inline]
__do_sys_fallocate fs/open.c:371 [inline]
__se_sys_fallocate fs/open.c:369 [inline]
__x64_sys_fallocate+0xc0/0x110 fs/open.c:369
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9c7eb8f749
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:00007ffd1029f7c8 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f9c7ede5fa0 RCX: 00007f9c7eb8f749
RDX: 0000000000004003 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007f9c7ec13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000010000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9c7ede5fa0 R14: 00007f9c7ede5fa0 R15: 0000000000000004
</TASK>
***
If these findings have caused you to resend the series or submit a
separate fix, please add the following tag to your commit message:
Tested-by: syzbot@syzkaller.appspotmail.com
---
This report is generated by a bot. It may contain errors.
syzbot ci engineers can be reached at syzkaller@googlegroups.com.
^ permalink raw reply [flat|nested] 2+ messages in thread