io_uring: remove unnecessary NULL checks

mainline inclusion
from mainline-5.6-rc3
commit 297a31e3
category: feature
bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=27
CVE: NA
---------------------------

The "kmsg" pointer can't be NULL and we have already dereferenced it so
a check here would be useless.
Reviewed-by: NStefano Garzarella <sgarzare@redhat.com>
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: Nyangerkun <yangerkun@huawei.com>
Reviewed-by: Nzhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: NCheng Jian <cj.chengjian@huawei.com>

fs/io_uring.c

@@ -3021,7 +3021,7 @@ static int io_sendmsg(struct io_kiocb *req, struct io_kiocb **nxt,
 			if (req->io)
 				return -EAGAIN;
 			if (io_alloc_async_ctx(req)) {
-				if (kmsg && kmsg->iov != kmsg->fast_iov)
+				if (kmsg->iov != kmsg->fast_iov)
 					kfree(kmsg->iov);
 				return -ENOMEM;
 			}
@@ -3175,7 +3175,7 @@ static int io_recvmsg(struct io_kiocb *req, struct io_kiocb **nxt,
 			if (req->io)
 				return -EAGAIN;
 			if (io_alloc_async_ctx(req)) {
-				if (kmsg && kmsg->iov != kmsg->fast_iov)
+				if (kmsg->iov != kmsg->fast_iov)
 					kfree(kmsg->iov);
 				return -ENOMEM;
 			}