published December 16, 2025
In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix memory leak in cifs_construct_tcon()
When having a multiuser mount with domain= specified and using
cifscreds, cifs_set_cifscreds() will end up setting @ctx->domainname,
so it needs to be freed before leaving cifs_construct_tcon().
This fixes the following memory leak reported by kmemleak:
mount.cifs //srv/share /mnt -o domain=ZELDA,multiuser,...
su - testuser
cifscreds add -d ZELDA -u testuser
...
ls /mnt/1
...
umount /mnt
echo scan > /sys/kernel/debug/kmemleak
cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff8881203c3f08 (size 8):
comm "ls", pid 5060, jiffies 4307222943
hex dump (first 8 bytes):
5a 45 4c 44 41 00 cc cc ZELDA...
backtrace (crc d109a8cf):
__kmalloc_node_track_caller_noprof+0x572/0x710
kstrdup+0x3a/0x70
cifs_sb_tlink+0x1209/0x1770 [cifs]
cifs_get_fattr+0xe1/0xf50 [cifs]
cifs_get_inode_info+0xb5/0x240 [cifs]
cifs_revalidate_dentry_attr+0x2d1/0x470 [cifs]
cifs_getattr+0x28e/0x450 [cifs]
vfs_getattr_nosec+0x126/0x180
vfs_statx+0xf6/0x220
do_statx+0xab/0x110
__x64_sys_statx+0xd5/0x130
do_syscall_64+0xbb/0x380
entry_SYSCALL_64_after_hwframe+0x77/0x7f