memory leak in kobject_set_name_vargs (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    c2e7554e Merge tag 'gfs2-v5.10-rc4-fixes' of git://git.ker..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=120277be500000
kernel config:  https://syzkaller.appspot.com/x/.config?x=dc8ee843c1fc6693
dashboard link: https://syzkaller.appspot.com/bug?extid=859119106243eb95085b
compiler:       gcc (GCC) 10.1.0-syz 20200507
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=172afce2500000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12c8a9d6500000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+859119106243eb95085b@xxxxxxxxxxxxxxxxxxxxxxxxx

BUG: memory leak
unreferenced object 0xffff8881110c8f40 (size 32):
  comm "syz-executor894", pid 8479, jiffies 4294942790 (age 8.030s)
  hex dump (first 32 bytes):
    6c 6f 6f 70 30 00 00 00 00 00 00 00 00 00 00 00  loop0...........
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<000000002a879a43>] kstrdup+0x36/0x70 mm/util.c:60
    [<0000000068356e6a>] kstrdup_const+0x53/0x80 mm/util.c:83
    [<00000000beef27f8>] kvasprintf_const+0xc2/0x110 lib/kasprintf.c:48
    [<00000000fa036169>] kobject_set_name_vargs+0x3b/0xe0 lib/kobject.c:289
    [<00000000c1ae635f>] kobject_add_varg lib/kobject.c:384 [inline]
    [<00000000c1ae635f>] kobject_init_and_add+0x6d/0xc0 lib/kobject.c:473
    [<0000000033a7e260>] nilfs_sysfs_create_device_group+0x98/0x3a0 fs/nilfs2/sysfs.c:999
    [<00000000ed96fbb9>] init_nilfs+0x523/0x680 fs/nilfs2/the_nilfs.c:637
    [<0000000047c27b86>] nilfs_fill_super fs/nilfs2/super.c:1046 [inline]
    [<0000000047c27b86>] nilfs_mount+0x51b/0x890 fs/nilfs2/super.c:1316
    [<00000000bc71acf1>] legacy_get_tree+0x2b/0x90 fs/fs_context.c:592
    [<000000004ee940ed>] vfs_get_tree+0x28/0x100 fs/super.c:1549
    [<00000000badf1d9b>] do_new_mount fs/namespace.c:2875 [inline]
    [<00000000badf1d9b>] path_mount+0xc5e/0x1170 fs/namespace.c:3205
    [<00000000214ca321>] do_mount fs/namespace.c:3218 [inline]
    [<00000000214ca321>] __do_sys_mount fs/namespace.c:3426 [inline]
    [<00000000214ca321>] __se_sys_mount fs/namespace.c:3403 [inline]
    [<00000000214ca321>] __x64_sys_mount+0x18e/0x1d0 fs/namespace.c:3403
    [<00000000106f08a7>] do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
    [<00000000534b6078>] entry_SYSCALL_64_after_hwframe+0x44/0xa9



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