cifs: fix leak in FSCTL_ENUM_SNAPS response handling

The server may respond with success, and an output buffer less than
sizeof(struct smb_snapshot_array) in length. Do not leak the output
buffer in this case.

Fixes: 834170c85978 ("Enable previous version support")
Signed-off-by: David Disseldorp <ddiss@suse.de>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>

diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 152e37f2ad9213462a2ae439296a6edb49d653f9..c58691834eb2b74fa34f3fe2661ed3e211c4d22e 100644 (file)
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -942,6 +942,7 @@ smb3_enum_snapshots(const unsigned int xid, struct cifs_tcon *tcon,
                }
                if (snapshot_in.snapshot_array_size < sizeof(struct smb_snapshot_array)) {
                        rc = -ERANGE;
+                       kfree(retbuf);
                        return rc;
                }