switch netlink_getsockbyfilp() to taking descriptor

the only call site (in do_mq_notify()) obtains the argument
from an immediately preceding fdget() and it is immediately
followed by fdput(); might as well just replace it with
a variant that would take a descriptor instead of struct file *
and have file lookups handled inside that function.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 1 insertions, 7 deletions

diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index 34fa0bd8bb11..fd05e3d4f7b6 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -1355,13 +1355,7 @@ static int do_mq_notify(mqd_t mqdes, const struct sigevent *notification)
 			skb_put(nc, NOTIFY_COOKIE_LEN);
 			/* and attach it to the socket */
 retry:
-			f = fdget(notification->sigev_signo);
-			if (!fd_file(f)) {
-				ret = -EBADF;
-				goto out;
-			}
-			sock = netlink_getsockbyfilp(fd_file(f));
-			fdput(f);
+			sock = netlink_getsockbyfd(notification->sigev_signo);
 			if (IS_ERR(sock)) {
 				ret = PTR_ERR(sock);
 				goto free_skb;