[NET]: File descriptor loss while receiving SCM_RIGHTS

If more than one file descriptor was sent with an SCM_RIGHTS message, and on the receiving end, after installing a nonzero (but not all) file descritpors the process runs out of fds, then the already installed fds will be lost (userspace will have no way of knowing about them). The following patch makes sure, that at least the already installed fds are sent to userspace. It doesn't solve the issue of losing file descriptors in case of an EFAULT on the userspace buffer. Signed-off-by: Miklos Szeredi <[email protected]> Signed-off-by: David S. Miller <[email protected]>
chewitt · Oct 12, 2006 · effee6a · effee6a
1 parent 6aa2551
commit effee6a
Show file tree

Hide file tree

Showing 2 changed files with 2 additions and 4 deletions.
diff --git a/net/compat.c b/net/compat.c
@@ -285,8 +285,7 @@ void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
 
 	if (i > 0) {
 		int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
-		if (!err)
-			err = put_user(SOL_SOCKET, &cm->cmsg_level);
+		err = put_user(SOL_SOCKET, &cm->cmsg_level);
 		if (!err)
 			err = put_user(SCM_RIGHTS, &cm->cmsg_type);
 		if (!err)

diff --git a/net/core/scm.c b/net/core/scm.c
@@ -245,8 +245,7 @@ void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm)
 	if (i > 0)
 	{
 		int cmlen = CMSG_LEN(i*sizeof(int));
-		if (!err)
-			err = put_user(SOL_SOCKET, &cm->cmsg_level);
+		err = put_user(SOL_SOCKET, &cm->cmsg_level);
 		if (!err)
 			err = put_user(SCM_RIGHTS, &cm->cmsg_type);
 		if (!err)