fix memory leak in CIFSFindNext

When CIFSFindNext gets back an -EBADF from a call, it sets the return
code of the function to 0 and eventually exits. Doing this makes the
cleanup at the end of the function skip freeing the SMB buffer, so
we need to make sure we free the buffer explicitly when doing this.

If we don't you end up with errors like this when unplugging the cifs
kernel module:

slab error in kmem_cache_destroy(): cache `cifs_request': Can't free all objects
 [<c046bdbf>] kmem_cache_destroy+0x61/0xf3
 [<e0f03045>] cifs_destroy_request_bufs+0x14/0x28 [cifs]
 [<e0f2016e>] exit_cifs+0x1e/0x80 [cifs]
 [<c043aeae>] sys_delete_module+0x192/0x1b8
 [<c04451fd>] audit_syscall_entry+0x14b/0x17d
 [<c0405413>] syscall_call+0x7/0xb
 =======================

Signed-off-by: Jeff Layton <jlayton@redhat.com>
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 95fbba4e..641cc8f 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -3679,6 +3679,7 @@
 	if (rc) {
 		if (rc == -EBADF) {
 			psrch_inf->endOfSearch = true;
+			cifs_buf_release(pSMB);
 			rc = 0; /* search probably was closed at end of search*/
 		} else
 			cFYI(1, ("FindNext returned = %d", rc));