From: Roy Marples <roy@marples.name>
Date: Mon, 5 Sep 2016 19:39:42 +0000 (+0000)
Subject: Handle NLMSG_NOOP and NLMSG_DONE.
X-Git-Tag: v6.11.4~50
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ee7545d027b99facdb8dedc0b960f4fb07b64bb0;p=thirdparty%2Fdhcpcd.git

Handle NLMSG_NOOP and NLMSG_DONE.
Move err_netlink to here as well to clarify.
---

diff --git a/if-linux.c b/if-linux.c
index c247b101..88a38981 100644
--- a/if-linux.c
+++ b/if-linux.c
@@ -313,26 +313,6 @@ if_closesockets_os(struct dhcpcd_ctx *ctx)
 	}
 }
 
-static int
-err_netlink(struct nlmsghdr *nlm)
-{
-	struct nlmsgerr *err;
-	size_t len;
-
-	if (nlm->nlmsg_type != NLMSG_ERROR)
-		return 0;
-	len = nlm->nlmsg_len - sizeof(*nlm);
-	if (len < sizeof(*err)) {
-		errno = EBADMSG;
-		return -1;
-	}
-	err = (struct nlmsgerr *)NLMSG_DATA(nlm);
-	if (err->error == 0)
-		return (int)len;
-	errno = -err->error;
-	return -1;
-}
-
 static int
 get_netlink(struct dhcpcd_ctx *ctx, struct interface *ifp, int fd, int flags,
     int (*callback)(struct dhcpcd_ctx *, struct interface *, struct nlmsghdr *))
@@ -366,13 +346,25 @@ get_netlink(struct dhcpcd_ctx *ctx, struct interface *ifp, int fd, int flags,
 	     nlm && NLMSG_OK(nlm, (size_t)bytes);
 	     nlm = NLMSG_NEXT(nlm, bytes))
 	{
-		if ((r = err_netlink(nlm)) == -1)
-			return -1;
-		if (r == 0 && callback) {
-			r = callback(ctx, ifp, nlm);
-			if (r != 0)
-				return r;
+		if (nlm->nlmsg_type == NLMSG_NOOP)
+			continue;
+		if (nlm->nlmsg_type == NLMSG_ERROR) {
+			struct nlmsgerr *err;
+
+			if (nlm->nlmsg_len - sizeof(*nlm) < sizeof(*err)) {
+				errno = EBADMSG;
+				return -1;
+			}
+			err = (struct nlmsgerr *)NLMSG_DATA(nlm);
+			if (err->error != 0) {
+				errno = -err->error;
+				return -1;
+			}
 		}
+		if (nlm->nlmsg_type == NLMSG_DONE)
+			break;
+		if ((r = callback(ctx, ifp, nlm)) != 0)
+			break;
 	}
 
 	return r;