[PATCH 4.9 01/64] cifs: release cifs root_cred after exit_cifs

From: Greg Kroah-Hartman
Date: Tue Oct 03 2017 - 08:24:04 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Shu Wang <shuwang@xxxxxxxxxx>

commit 94183331e815617246b1baa97e0916f358c794bb upstream.

memory leak was found by kmemleak. exit_cifs_spnego
should be called before cifs module removed, or
cifs root_cred will not be released.

kmemleak report:
unreferenced object 0xffff880070a3ce40 (size 192):
backtrace:
kmemleak_alloc+0x4a/0xa0
kmem_cache_alloc+0xc7/0x1d0
prepare_kernel_cred+0x20/0x120
init_cifs_spnego+0x2d/0x170 [cifs]
0xffffffffc07801f3
do_one_initcall+0x51/0x1b0
do_init_module+0x60/0x1fd
load_module+0x161e/0x1b60
SYSC_finit_module+0xa9/0x100
SyS_finit_module+0xe/0x10

Signed-off-by: Shu Wang <shuwang@xxxxxxxxxx>
Signed-off-by: Steve French <smfrench@xxxxxxxxx>
Reviewed-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/cifs/cifsfs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -1360,7 +1360,7 @@ exit_cifs(void)
exit_cifs_idmap();
#endif
#ifdef CONFIG_CIFS_UPCALL
- unregister_key_type(&cifs_spnego_key_type);
+ exit_cifs_spnego();
#endif
cifs_destroy_request_bufs();
cifs_destroy_mids();