[PATCH 5.4 234/270] 9p: Fix memory leak in v9fs_mount

From: Greg Kroah-Hartman
Date: Mon Aug 17 2020 - 14:05:39 EST


From: Zheng Bin <zhengbin13@xxxxxxxxxx>

commit cb0aae0e31c632c407a2cab4307be85a001d4d98 upstream.

v9fs_mount
v9fs_session_init
v9fs_cache_session_get_cookie
v9fs_random_cachetag -->alloc cachetag
v9ses->fscache = fscache_acquire_cookie -->maybe NULL
sb = sget -->fail, goto clunk
clunk_fid:
v9fs_session_close
if (v9ses->fscache) -->NULL
kfree(v9ses->cachetag)

Thus memleak happens.

Link: http://lkml.kernel.org/r/20200615012153.89538-1-zhengbin13@xxxxxxxxxx
Fixes: 60e78d2c993e ("9p: Add fscache support to 9p")
Cc: <stable@xxxxxxxxxxxxxxx> # v2.6.32+
Signed-off-by: Zheng Bin <zhengbin13@xxxxxxxxxx>
Signed-off-by: Dominique Martinet <asmadeus@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/9p/v9fs.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

--- a/fs/9p/v9fs.c
+++ b/fs/9p/v9fs.c
@@ -500,10 +500,9 @@ void v9fs_session_close(struct v9fs_sess
}

#ifdef CONFIG_9P_FSCACHE
- if (v9ses->fscache) {
+ if (v9ses->fscache)
v9fs_cache_session_put_cookie(v9ses);
- kfree(v9ses->cachetag);
- }
+ kfree(v9ses->cachetag);
#endif
kfree(v9ses->uname);
kfree(v9ses->aname);