WARNING in sysfs_create_dir_ns (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 9d5c0b3a8e1a Linux 4.14.295
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16a3bda8880000
kernel config: https://syzkaller.appspot.com/x/.config?x=746c079015a92425
dashboard link: https://syzkaller.appspot.com/bug?extid=5bb9a47a1a20f62e4182
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ed6fcf5895a2/disk-9d5c0b3a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/341aa3534116/vmlinux-9d5c0b3a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5bb9a4...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 0 PID: 10086 at fs/sysfs/dir.c:30 sysfs_warn_dup.cold+0x17/0x26 fs/sysfs/dir.c:30
Kernel panic - not syncing: panic_on_warn set ...

shmem_alloc_and_acct_page+0x126/0x620 mm/shmem.c:1505
shmem_getpage_gfp+0x302/0x2a40 mm/shmem.c:1782
shmem_getpage mm/shmem.c:131 [inline]
shmem_write_begin+0xeb/0x190 mm/shmem.c:2431
generic_perform_write+0x1c9/0x420 mm/filemap.c:3055
__generic_file_write_iter+0x227/0x590 mm/filemap.c:3180
generic_file_write_iter+0x36f/0x650 mm/filemap.c:3208
call_write_iter include/linux/fs.h:1780 [inline]
new_sync_write fs/read_write.c:469 [inline]
__vfs_write+0x44c/0x630 fs/read_write.c:482
vfs_write+0x17f/0x4d0 fs/read_write.c:544
SYSC_pwrite64 fs/read_write.c:632 [inline]
SyS_pwrite64+0x116/0x140 fs/read_write.c:619
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f140fbdc707
RSP: 002b:00007f140e59df00 EFLAGS: 00000293 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 000000000000025d RCX: 00007f140fbdc707
RDX: 0000000000000020 RSI: 0000000020010100 RDI: 0000000000000004
RBP: 0000000000000004 R08: 0000000000000000 R09: 00007f140e59e1d0
R10: 0000000000002000 R11: 0000000000000293 R12: 0000000000000004
R13: 0000000020000230 R14: 0000000000000002 R15: 00007f140fc74a20
CPU: 0 PID: 10086 Comm: syz-executor.1 Not tainted 4.14.295-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x1b2/0x281 lib/dump_stack.c:58
panic+0x1f9/0x42d kernel/panic.c:183
__warn.cold+0x20/0x44 kernel/panic.c:547
report_bug+0x208/0x250 lib/bug.c:183
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:964
RIP: 0010:sysfs_warn_dup.cold+0x17/0x26 fs/sysfs/dir.c:30
RSP: 0018:ffff888055dcf728 EFLAGS: 00010282
RAX: 000000000000003a RBX: ffff888053924190 RCX: 0000000000000000
RDX: 000000000002e74f RSI: ffffffff81443130 RDI: ffffed100abb9edb
RBP: ffff8880538c2e40 R08: 000000000000003a R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8882393dac40
R13: ffff8880b4bf6d00 R14: ffff888053924198 R15: ffff88805500c158
sysfs_create_dir_ns+0x16f/0x1d0 fs/sysfs/dir.c:59
create_dir lib/kobject.c:71 [inline]
kobject_add_internal+0x28b/0x930 lib/kobject.c:229
kobject_add_varg lib/kobject.c:364 [inline]
kobject_init_and_add+0xde/0x120 lib/kobject.c:436
gfs2_sys_fs_add+0x184/0x3f0 fs/gfs2/sys.c:652
fill_super+0x118b/0x2310 fs/gfs2/ops_fstype.c:1122
gfs2_mount+0x439/0x510 fs/gfs2/ops_fstype.c:1335
mount_fs+0x92/0x2a0 fs/super.c:1237
vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046
vfs_kern_mount fs/namespace.c:1036 [inline]
do_new_mount fs/namespace.c:2572 [inline]
do_mount+0xe65/0x2a30 fs/namespace.c:2905
SYSC_mount fs/namespace.c:3121 [inline]
SyS_mount+0xa8/0x120 fs/namespace.c:3098
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f8f308e5ada
RSP: 002b:00007f8f2f257f88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007f8f308e5ada
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f8f2f257fe0
RBP: 00007f8f2f258020 R08: 00007f8f2f258020 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000
R13: 0000000020000100 R14: 00007f8f2f257fe0 R15: 0000000020047a20
Kernel Offset: disabled
Rebooting in 86400 seconds..


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