[lkml]   [2020]   [Jun]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH] cifs: Fix cached_fid refcnt leak in open_shroot
open_shroot() invokes kref_get(), which increases the refcount of the
"tcon->crfid" object. When open_shroot() returns not zero, it means the
open operation failed and close_shroot() will not be called to decrement
the refcount of the "tcon->crfid".

The reference counting issue happens in one normal path of
open_shroot(). When the cached root have been opened successfully in a
concurrent process, the function increases the refcount and jump to
"oshr_free" to return. However the current return value "rc" may not
equal to 0, thus the increased refcount will not be balanced outside the
function, causing a refcnt leak.

Fix this issue by setting the value of "rc" to 0 before jumping to
"oshr_free" label.

Signed-off-by: Xiyu Yang <>
Signed-off-by: Xin Tan <>
fs/cifs/smb2ops.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 736d86b8a910..28553d45604e 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -763,6 +763,7 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon,
/* close extra handle outside of crit sec */
SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
+ rc = 0;
goto oshr_free;

 \ /
  Last update: 2020-06-13 14:29    [W:0.026 / U:0.036 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site