[syzbot] [ext4?] WARNING in setattr_copy

[syzbot] [ext4?] WARNING in setattr_copy

[syzbot]

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@kernel.org>
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@syzkaller.appspotmail.com
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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For information about bisection process see: https://goo.gl/tpsmEJ#bisection

If the bug is already fixed, 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 bug's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the bug is a duplicate of another bug, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

Re: [syzbot] [ext4?] WARNING in setattr_copy

[Christian Brauner]

On Fri, Sep 15, 2023 at 11:51:54PM -0700, syzbot wrote:
> 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@kernel.org>
> 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@syzkaller.appspotmail.com
> Fixes: d6f106662147 ("fs: have setattr_copy handle multigrain timestamps appropriately")

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git f8edd33686154b9165457c95e2ed5943e916781e

Re: [syzbot] [ext4?] WARNING in setattr_copy

[Christian Brauner]

On Fri, Sep 15, 2023 at 11:51:54PM -0700, syzbot wrote:
> 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@kernel.org>
> 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@syzkaller.appspotmail.com
> Fixes: d6f106662147 ("fs: have setattr_copy handle multigrain timestamps appropriately")

#syz unset subsystems: ext4
#syz set subsystems: overlayfs

Re: [syzbot] [ext4?] WARNING in setattr_copy

[syzbot]

> On Fri, Sep 15, 2023 at 11:51:54PM -0700, syzbot wrote:
>> 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@kernel.org>
>> 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@syzkaller.appspotmail.com
>> Fixes: d6f106662147 ("fs: have setattr_copy handle multigrain timestamps appropriately")
>
> #syz unset subsystems: ext4
> #syz set subsystems: overlayfs

Command #1:
The following labels did not exist: subsystems:, ext4

Re: [syzbot] [overlayfs] WARNING in setattr_copy

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+450a6d7e0a2db0d8326a@syzkaller.appspotmail.com

Tested on:

commit:         f8edd336 overlayfs: set ctime when setting mtime and a..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
console output: https://syzkaller.appspot.com/x/log.txt?x=124fa964680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f4894cf58531f
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

Note: no patches were applied.
Note: testing is done by a robot and is best-effort only.