On Wed, Sep 11, 2019 at 11:30:08AM -0300, Marcelo Ricardo Leitner wrote:

On Wed, Sep 11, 2019 at 11:30:38AM +0300, Dan Carpenter wrote:

quoted

On Wed, Sep 11, 2019 at 09:30:47AM +0800, maowenan wrote:

quoted

On 2019/9/11 3:22, Dan Carpenter wrote:

quoted

On Tue, Sep 10, 2019 at 09:57:10PM +0300, Dan Carpenter wrote:

quoted

On Tue, Sep 10, 2019 at 03:13:42PM +0800, Mao Wenan wrote:

quoted

There are more parentheses in if clause when call sctp_get_port_local
in sctp_do_bind, and redundant assignment to 'ret'. This patch is to
do cleanup.

Signed-off-by: Mao Wenan <redacted>
---
 net/sctp/socket.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 9d1f83b10c0a..766b68b55ebe 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c

@@ -399,9 +399,8 @@ static int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
 	 * detection.
 	 */
 	addr->v4.sin_port = htons(snum);
-	if ((ret = sctp_get_port_local(sk, addr))) {
+	if (sctp_get_port_local(sk, addr))
 		return -EADDRINUSE;

sctp_get_port_local() returns a long which is either 0,1 or a pointer
casted to long.  It's not documented what it means and neither of the
callers use the return since commit 62208f12451f ("net: sctp: simplify
sctp_get_port").

Actually it was commit 4e54064e0a13 ("sctp: Allow only 1 listening
socket with SO_REUSEADDR") from 11 years ago.  That patch fixed a bug,
because before the code assumed that a pointer casted to an int was the
same as a pointer casted to a long.

commit 4e54064e0a13 treated non-zero return value as unexpected, so the current
cleanup is ok?

Yeah.  It's fine, I was just confused why we weren't preserving the
error code and then I saw that we didn't return errors at all and got
confused.

But please lets seize the moment and do the change Dean suggested.

*Dan*, sorry.

This was the last place saving this return value somewhere. It makes
sense to cleanup sctp_get_port_local() now and remove that masked
pointer return.

Then you may also cleanup:
socket.c:       return !!sctp_get_port_local(sk, &addr);
as it will be a direct map.

  Marcelo