From: Xiyu Yang xiyuyang19@fudan.edu.cn
commit 77577de64167aa0643d47ffbaacf3642632b321b upstream.
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 xiyuyang19@fudan.edu.cn Signed-off-by: Xin Tan tanxin.ctf@gmail.com Signed-off-by: Steve French stfrench@microsoft.com CC: Stable stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/cifs/smb2ops.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 58915d882285c..f5e893ed48aaa 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -736,6 +736,7 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon, struct cifs_fid *pfid) /* close extra handle outside of crit sec */ SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid); } + rc = 0; goto oshr_free; }