Hi Christian, Could you take this through your VFS tree please? > The following memory leak was reported after unbinding /dev/cachefiles: > > ================================================================== > unreferenced object 0xffff9b674176e3c0 (size 192): > comm "cachefilesd2", pid 680, jiffies 4294881224 > hex dump (first 32 bytes): > 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace (crc ea38a44b): > [<ffffffff8eb8a1a5>] kmem_cache_alloc+0x2d5/0x370 > [<ffffffff8e917f86>] prepare_creds+0x26/0x2e0 > [<ffffffffc002eeef>] cachefiles_determine_cache_security+0x1f/0x120 > [<ffffffffc00243ec>] cachefiles_add_cache+0x13c/0x3a0 > [<ffffffffc0025216>] cachefiles_daemon_write+0x146/0x1c0 > [<ffffffff8ebc4a3b>] vfs_write+0xcb/0x520 > [<ffffffff8ebc5069>] ksys_write+0x69/0xf0 > [<ffffffff8f6d4662>] do_syscall_64+0x72/0x140 > [<ffffffff8f8000aa>] entry_SYSCALL_64_after_hwframe+0x6e/0x76 > ================================================================== > > Put the reference count of cache_cred in cachefiles_daemon_unbind() to > fix the problem. And also put cache_cred in cachefiles_add_cache() error > branch to avoid memory leaks. > > Fixes: 9ae326a69004 ("CacheFiles: A cache that backs onto a mounted filesystem") > CC: stable@xxxxxxxxxxxxxxx > Signed-off-by: Baokun Li <libaokun1@xxxxxxxxxx> and add: Reviewed-by: Jingbo Xu <jefflexu@xxxxxxxxxxxxxxxxx> Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx> Acked-by: David Howells <dhowells@xxxxxxxxxx>