syzbot


WARNING in ext4_xattr_inode_lookup_create

Status: upstream: reported C repro on 2024/05/28 15:21
Subsystems: ext4
[Documentation on labels]
Reported-by: syzbot+fe42a669c87e4a980051@syzkaller.appspotmail.com
First crash: 22d, last: 7d21h
Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: BUG: unable to handle kernel NULL pointer dereference in ext4_xattr_set_entry (log)
Repro: C syz .config
  
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] fs/dcache: fix warning in ext4_xattr_inode_lookup_create 3 (3) 2024/05/29 02:01
[syzbot] [ext4?] WARNING in ext4_xattr_inode_lookup_create 1 (3) 2024/05/29 00:53
Last patch testing requests (2)
Created Duration User Patch Repo Result
2024/06/07 18:15 1h27m retest repro upstream report log
2024/05/29 00:14 23m eadavis@qq.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 8f6a15f095a6 OK log

Sample crash report:
EXT4-fs warning (device loop0): ext4_xattr_inode_create:1471: refuse to create EA inode when umounting
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5082 at fs/ext4/xattr.c:1472 ext4_xattr_inode_create fs/ext4/xattr.c:1472 [inline]
WARNING: CPU: 0 PID: 5082 at fs/ext4/xattr.c:1472 ext4_xattr_inode_lookup_create+0xc38/0x1ea0 fs/ext4/xattr.c:1590
Modules linked in:
CPU: 0 PID: 5082 Comm: syz-executor226 Not tainted 6.9.0-syzkaller-10323-g8f6a15f095a6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:ext4_xattr_inode_create fs/ext4/xattr.c:1472 [inline]
RIP: 0010:ext4_xattr_inode_lookup_create+0xc38/0x1ea0 fs/ext4/xattr.c:1590
Code: 18 e9 b4 03 00 00 4d 89 e5 e8 24 5d 2c ff 4c 89 ff 48 c7 c6 28 a4 b8 8d ba bf 05 00 00 48 c7 c1 40 a1 df 8b e8 39 15 fc ff 90 <0f> 0b 90 49 c7 c4 ea ff ff ff 4c 8b 74 24 68 4c 8b 7c 24 18 e9 96
RSP: 0018:ffffc900034a7120 EFLAGS: 00010246
RAX: 347f6253c1206700 RBX: 0000000000000000 RCX: 347f6253c1206700
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc900034a72f0 R08: ffffffff8176a12c R09: 1ffff92000694d9c
R10: dffffc0000000000 R11: fffff52000694d9d R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffc900034a7230 R15: ffff888023e3c000
FS:  0000555564020380(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555640296f8 CR3: 0000000078050000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ext4_xattr_block_set+0x277/0x3880 fs/ext4/xattr.c:1910
 ext4_xattr_move_to_block fs/ext4/xattr.c:2663 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2738 [inline]
 ext4_expand_extra_isize_ea+0x12d7/0x1cf0 fs/ext4/xattr.c:2830
 __ext4_expand_extra_isize+0x2fb/0x3e0 fs/ext4/inode.c:5782
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5825 [inline]
 __ext4_mark_inode_dirty+0x524/0x880 fs/ext4/inode.c:5903
 ext4_dirty_inode+0xce/0x110 fs/ext4/inode.c:5935
 __mark_inode_dirty+0x325/0xe20 fs/fs-writeback.c:2486
 mark_inode_dirty_sync include/linux/fs.h:2421 [inline]
 iput+0x1fe/0x930 fs/inode.c:1764
 __dentry_kill+0x20d/0x630 fs/dcache.c:603
 shrink_kill+0xa9/0x2c0 fs/dcache.c:1048
 shrink_dentry_list+0x2c0/0x5b0 fs/dcache.c:1075
 shrink_dcache_parent+0xcb/0x3b0
 do_one_tree+0x23/0xe0 fs/dcache.c:1538
 shrink_dcache_for_umount+0x7d/0x130 fs/dcache.c:1555
 generic_shutdown_super+0x6a/0x2d0 fs/super.c:620
 kill_block_super+0x44/0x90 fs/super.c:1676
 ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7319
 deactivate_locked_super+0xc4/0x130 fs/super.c:473
 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1267
 task_work_run+0x24f/0x310 kernel/task_work.c:180
 ptrace_notify+0x2d2/0x380 kernel/signal.c:2404
 ptrace_report_syscall include/linux/ptrace.h:415 [inline]
 ptrace_report_syscall_exit include/linux/ptrace.h:477 [inline]
 syscall_exit_work+0xc6/0x190 kernel/entry/common.c:173
 syscall_exit_to_user_mode_prepare kernel/entry/common.c:200 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:205 [inline]
 syscall_exit_to_user_mode+0x273/0x370 kernel/entry/common.c:218
 do_syscall_64+0x102/0x240 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f15671fa587
Code: 07 00 48 83 c4 08 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffeafe5a078 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f15671fa587
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffeafe5a130
RBP: 00007ffeafe5a130 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000206 R12: 00007ffeafe5b1a0
R13: 00005555640216c0 R14: 431bde82d7b634db R15: 00007ffeafe5b1c0
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/24 16:34 upstream 8f6a15f095a6 8f98448e .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-smack-root WARNING in ext4_xattr_inode_lookup_create
2024/05/24 15:17 upstream 8f6a15f095a6 8f98448e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in ext4_xattr_inode_lookup_create
2024/05/24 15:14 upstream 8f6a15f095a6 8f98448e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in ext4_xattr_inode_lookup_create
* Struck through repros no longer work on HEAD.