[syzbot] [fs?] memory leak in debugfs_change_name

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 8f7aa3d3c732 Merge tag 'net-next-6.19' of git://git.kernel..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1350c01a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=3bdbe6509b080086
dashboard link: https://syzkaller.appspot.com/bug?extid=3d7ca9c802c547f8550a
compiler: gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13b9d192580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10aceab4580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/75704c8ef83a/disk-8f7aa3d3.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fc039c7b45ea/vmlinux-8f7aa3d3.xz
kernel image: https://storage.googleapis.com/syzbot-assets/80c77928126a/bzImage-8f7aa3d3.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3d7ca9...@syzkaller.appspotmail.com

BUG: memory leak
unreferenced object 0xffff8881110bb308 (size 8):
comm "syz.0.17", pid 6090, jiffies 4294942958
hex dump (first 8 bytes):
2e 00 00 00 00 00 00 00 ........
backtrace (crc ecfc7064):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5258 [inline]
__do_kmalloc_node mm/slub.c:5651 [inline]
__kmalloc_node_track_caller_noprof+0x3b2/0x670 mm/slub.c:5759
__kmemdup_nul mm/util.c:64 [inline]
kstrdup+0x3c/0x80 mm/util.c:84
kstrdup_const+0x63/0x80 mm/util.c:104
kvasprintf_const+0xca/0x110 lib/kasprintf.c:48
debugfs_change_name+0xf6/0x5d0 fs/debugfs/inode.c:854
cfg80211_dev_rename+0xd8/0x110 net/wireless/core.c:149
nl80211_set_wiphy+0x102/0x1770 net/wireless/nl80211.c:3844
genl_family_rcv_msg_doit+0x11e/0x190 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x2fd/0x440 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x93/0x1d0 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x3a3/0x4f0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x335/0x6b0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:733 [inline]
____sys_sendmsg+0x562/0x5a0 net/socket.c:2608
___sys_sendmsg+0xc8/0x130 net/socket.c:2662
__sys_sendmsg+0xc7/0x140 net/socket.c:2694

connection error: failed to recv *flatrpc.ExecutorMessageRawT: EOF


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