[syzbot] [ext4?] WARNING in setattr_copy

From: syzbot
Date: Sat Sep 16 2023 - 02:53:26 EST


Hello,

syzbot found the following issue on:

HEAD commit: 3c13c772fc23 Add linux-next specific files for 20230912
git tree: linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=15b02b0c680000
kernel config: https://syzkaller.appspot.com/x/.config?x=f7149cbda1664bc5
dashboard link: https://syzkaller.appspot.com/bug?extid=450a6d7e0a2db0d8326a
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=155b32b4680000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12cf6028680000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/eb6fbc71f83a/disk-3c13c772.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2d671ade67d9/vmlinux-3c13c772.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b2b7190a3a61/bzImage-3c13c772.xz

The issue was bisected to:

commit d6f106662147d78e9a439608e8deac7d046ca0fa
Author: Jeff Layton <jlayton@xxxxxxxxxx>
Date: Wed Aug 30 18:28:43 2023 +0000

fs: have setattr_copy handle multigrain timestamps appropriately

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1419f8d8680000
final oops: https://syzkaller.appspot.com/x/report.txt?x=1619f8d8680000
console output: https://syzkaller.appspot.com/x/log.txt?x=1219f8d8680000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+450a6d7e0a2db0d8326a@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: d6f106662147 ("fs: have setattr_copy handle multigrain timestamps appropriately")

overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off.
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5042 at fs/attr.c:298 setattr_copy_mgtime fs/attr.c:298 [inline]
WARNING: CPU: 0 PID: 5042 at fs/attr.c:298 setattr_copy+0x84c/0x950 fs/attr.c:355
Modules linked in:
CPU: 0 PID: 5042 Comm: syz-executor172 Not tainted 6.6.0-rc1-next-20230912-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
RIP: 0010:setattr_copy_mgtime fs/attr.c:298 [inline]
RIP: 0010:setattr_copy+0x84c/0x950 fs/attr.c:355
Code: 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 66 83 3c 02 00 0f 85 ff 00 00 00 4c 89 73 68 4c 89 7b 70 e9 9d fd ff ff e8 74 a8 92 ff <0f> 0b e9 91 fd ff ff 4c 89 ff e8 b5 93 e8 ff e9 69 f8 ff ff e8 ab
RSP: 0018:ffffc900038cf268 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888076c766b0 RCX: 0000000000000000
RDX: ffff88807926d940 RSI: ffffffff81f54afc RDI: 0000000000000005
RBP: ffffc900038cf2a0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000030 R11: ffffffff81ddb7d3 R12: ffffc900038cf420
R13: 0000000000000030 R14: 0000000000000000 R15: ffff888076c766d8
FS: 00005555574de380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020001000 CR3: 000000001fdba000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ext4_setattr+0x36f/0x2990 fs/ext4/inode.c:5479
notify_change+0x742/0x11c0 fs/attr.c:539
ovl_do_notify_change fs/overlayfs/overlayfs.h:188 [inline]
ovl_set_timestamps.isra.0+0x168/0x1e0 fs/overlayfs/copy_up.c:345
ovl_set_attr.part.0+0x1c8/0x210 fs/overlayfs/copy_up.c:369
ovl_set_attr+0x1c9/0x200 fs/overlayfs/copy_up.c:372
ovl_copy_up_metadata+0x471/0x6c0 fs/overlayfs/copy_up.c:668
ovl_copy_up_workdir fs/overlayfs/copy_up.c:747 [inline]
ovl_do_copy_up fs/overlayfs/copy_up.c:905 [inline]
ovl_copy_up_one+0xb10/0x2f10 fs/overlayfs/copy_up.c:1091
ovl_copy_up_flags+0x189/0x200 fs/overlayfs/copy_up.c:1146
ovl_setattr+0x109/0x520 fs/overlayfs/inode.c:45
notify_change+0x742/0x11c0 fs/attr.c:539
chown_common+0x596/0x660 fs/open.c:783
do_fchownat+0x140/0x1f0 fs/open.c:814
__do_sys_lchown fs/open.c:839 [inline]
__se_sys_lchown fs/open.c:837 [inline]
__x64_sys_lchown+0x7e/0xc0 fs/open.c:837
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f9f835ef429
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffbe3679e8 EFLAGS: 00000246 ORIG_RAX: 000000000000005e
RAX: ffffffffffffffda RBX: 69662f7375622f2e RCX: 00007f9f835ef429
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200002c0
RBP: 0079616c7265766f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fffbe367bc8 R14: 0000000000000001 R15: 0000000000000001
</TASK>


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