| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <000000000000b1b164061f96213d@google.com>
Date: Tue, 13 Aug 2024 13:05:31 -0700
From: syzbot <syzbot+1ad8bac5af24d01e2cbd@...kaller.appspotmail.com>
To: adilger.kernel@...ger.ca, jack@...e.cz, linux-ext4@...r.kernel.org,
linux-kernel@...r.kernel.org, ojaswin@...ux.ibm.com,
syzkaller-bugs@...glegroups.com, tytso@....edu
Subject: [syzbot] [ext4?] divide error in ext4_mb_regular_allocator
Hello,
syzbot found the following issue on:
HEAD commit: ee9a43b7cfe2 Merge tag 'net-6.11-rc3' of git://git.kernel...
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1655c15d980000
kernel config: https://syzkaller.appspot.com/x/.config?x=9358cc4a2e37fd30
dashboard link: https://syzkaller.appspot.com/bug?extid=1ad8bac5af24d01e2cbd
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15a8fbc9980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17bc726d980000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e6062f24de48/disk-ee9a43b7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5d3ec6153dbd/vmlinux-ee9a43b7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/98dbabb91d02/bzImage-ee9a43b7.xz
mounted in repro #1: https://storage.googleapis.com/syzbot-assets/4dd4c0acf870/mount_0.gz
mounted in repro #2: https://storage.googleapis.com/syzbot-assets/ca52271baf46/mount_1.gz
The issue was bisected to:
commit 1f6bc02f18489b9c9ea39b068d0695fb0e4567e9
Author: Ojaswin Mujoo <ojaswin@...ux.ibm.com>
Date: Fri Dec 15 11:19:50 2023 +0000
ext4: fallback to complex scan if aligned scan doesn't work
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=118a3d11980000
final oops: https://syzkaller.appspot.com/x/report.txt?x=138a3d11980000
console output: https://syzkaller.appspot.com/x/log.txt?x=158a3d11980000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1ad8bac5af24d01e2cbd@...kaller.appspotmail.com
Fixes: 1f6bc02f1848 ("ext4: fallback to complex scan if aligned scan doesn't work")
EXT4-fs: Ignoring removed oldalloc option
EXT4-fs (loop0): re-mounted 00000000-0000-0000-0000-000000000000 r/w. Quota mode: none.
Oops: divide error: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 5224 Comm: syz-executor196 Not tainted 6.11.0-rc2-syzkaller-00111-gee9a43b7cfe2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:ext4_mb_regular_allocator+0x1687/0x3b80 fs/ext4/mballoc.c:2932
Code: 16 00 00 8b 1a bf 40 00 00 00 89 de e8 e2 ab 38 ff 48 83 fb 3f 0f 87 9f 19 00 00 e8 93 a7 38 ff 89 d9 49 d3 ec 4c 89 f8 31 d2 <49> f7 f4 48 89 d3 31 ff 48 89 d6 e8 59 ac 38 ff 83 bc 24 64 01 00
RSP: 0018:ffffc9000341e740 EFLAGS: 00010246
RAX: 0000000000000001 RBX: 0000000000000004 RCX: 0000000000000004
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000040
RBP: ffffc9000341e9f0 R08: ffffffff825acf3e R09: ffffffff825bea62
R10: 0000000000000005 R11: ffff8880282b1e00 R12: 0000000000000000
R13: 0000000000000003 R14: ffff8880663270e0 R15: 0000000000000001
FS: 0000555592670380(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe13f0d000 CR3: 0000000025072000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ext4_mb_new_blocks+0x10a8/0x4e30 fs/ext4/mballoc.c:6219
ext4_ext_map_blocks+0x1c74/0x77b0 fs/ext4/extents.c:4318
ext4_map_blocks+0xa5e/0x1d20 fs/ext4/inode.c:652
_ext4_get_block+0x239/0x6b0 fs/ext4/inode.c:794
ext4_get_block_unwritten+0x2f/0x100 fs/ext4/inode.c:827
__block_write_begin_int+0x50c/0x1a70 fs/buffer.c:2125
ext4_try_to_write_inline_data+0x7ed/0x1360 fs/ext4/inline.c:739
ext4_write_begin+0x2a0/0x10e0 fs/ext4/inode.c:1172
ext4_da_write_begin+0x300/0xa70 fs/ext4/inode.c:2943
generic_perform_write+0x399/0x840 mm/filemap.c:4019
ext4_buffered_write_iter+0xc6/0x350 fs/ext4/file.c:299
ext4_file_write_iter+0x1de/0x1a10
do_iter_readv_writev+0x60a/0x890
vfs_writev+0x37c/0xbb0 fs/read_write.c:971
do_pwritev fs/read_write.c:1072 [inline]
__do_sys_pwritev2 fs/read_write.c:1131 [inline]
__se_sys_pwritev2+0x1ca/0x2d0 fs/read_write.c:1122
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb9c91a61d9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe13f0c6c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007fb9c91ef095 RCX: 00007fb9c91a61d9
RDX: 000000000000000f RSI: 00000000200002c0 RDI: 0000000000000004
RBP: 0031656c69662f2e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000a12 R11: 0000000000000246 R12: 70756f7267647362
R13: 7461785f72657375 R14: 431bde82d7b634db R15: 00007fb9c91ef03b
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_mb_regular_allocator+0x1687/0x3b80 fs/ext4/mballoc.c:2932
Code: 16 00 00 8b 1a bf 40 00 00 00 89 de e8 e2 ab 38 ff 48 83 fb 3f 0f 87 9f 19 00 00 e8 93 a7 38 ff 89 d9 49 d3 ec 4c 89 f8 31 d2 <49> f7 f4 48 89 d3 31 ff 48 89 d6 e8 59 ac 38 ff 83 bc 24 64 01 00
RSP: 0018:ffffc9000341e740 EFLAGS: 00010246
RAX: 0000000000000001 RBX: 0000000000000004 RCX: 0000000000000004
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000040
RBP: ffffc9000341e9f0 R08: ffffffff825acf3e R09: ffffffff825bea62
R10: 0000000000000005 R11: ffff8880282b1e00 R12: 0000000000000000
R13: 0000000000000003 R14: ffff8880663270e0 R15: 0000000000000001
FS: 0000555592670380(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe13f0d000 CR3: 0000000025072000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 00 00 add %al,(%rax)
2: 8b 1a mov (%rdx),%ebx
4: bf 40 00 00 00 mov $0x40,%edi
9: 89 de mov %ebx,%esi
b: e8 e2 ab 38 ff call 0xff38abf2
10: 48 83 fb 3f cmp $0x3f,%rbx
14: 0f 87 9f 19 00 00 ja 0x19b9
1a: e8 93 a7 38 ff call 0xff38a7b2
1f: 89 d9 mov %ebx,%ecx
21: 49 d3 ec shr %cl,%r12
24: 4c 89 f8 mov %r15,%rax
27: 31 d2 xor %edx,%edx
* 29: 49 f7 f4 div %r12 <-- trapping instruction
2c: 48 89 d3 mov %rdx,%rbx
2f: 31 ff xor %edi,%edi
31: 48 89 d6 mov %rdx,%rsi
34: e8 59 ac 38 ff call 0xff38ac92
39: 83 .byte 0x83
3a: bc 24 64 01 00 mov $0x16424,%esp
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@...glegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
Powered by blists - more mailing lists