tests: extend checking of NLMSG_DONE decoding

* tests/netlink_protocol.c (test_nlmsg_done):  Use designated
initializers.  Check decoding of messages with non-integer payload.

diff --git a/tests/netlink_protocol.c b/tests/netlink_protocol.c
index 121c83d0994f0f20113efba47630ccd558c530b1..89b3c0a491f4477f2bf9f7d9f52f8ad0ac2ce080 100644 (file)
--- a/tests/netlink_protocol.c
+++ b/tests/netlink_protocol.c
@@ -318,16 +318,17 @@ static void
 test_nlmsg_done(const int fd)
 {
        struct nlmsghdr *nlh;
-       int total_len;
        void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
        long rc;
+       const int num = 0xfacefeed;
 
+       /* NLMSG_DONE message without enough room for an integer payload */
        nlh = nlh0;
-       nlh->nlmsg_len = NLMSG_HDRLEN + sizeof(int);
-       nlh->nlmsg_type = NLMSG_DONE;
-       nlh->nlmsg_flags = NLM_F_MULTI;
-       nlh->nlmsg_seq = 0;
-       nlh->nlmsg_pid = 0;
+       *nlh = (struct nlmsghdr) {
+               .nlmsg_len = NLMSG_HDRLEN + sizeof(num),
+               .nlmsg_type = NLMSG_DONE,
+               .nlmsg_flags = NLM_F_MULTI
+       };
 
        rc = sendto(fd, nlh, nlh->nlmsg_len, MSG_DONTWAIT, NULL, 0);
        printf("sendto(%d, {{len=%u, type=NLMSG_DONE, flags=NLM_F_MULTI"
@@ -335,19 +336,31 @@ test_nlmsg_done(const int fd)
               fd, nlh->nlmsg_len, nlh0 + NLMSG_HDRLEN,
               nlh->nlmsg_len, sprintrc(rc));
 
-       nlh = nlh0 - sizeof(int);
-       nlh->nlmsg_len = NLMSG_HDRLEN + sizeof(int);
-       nlh->nlmsg_type = NLMSG_DONE;
-       nlh->nlmsg_flags = NLM_F_MULTI;
-       nlh->nlmsg_seq = 0;
-       nlh->nlmsg_pid = 0;
-       total_len = nlh->nlmsg_len;
-       memcpy(NLMSG_DATA(nlh), &total_len, sizeof(total_len));
+       /* NLMSG_DONE message with enough room for an oddly short payload */
+       nlh->nlmsg_len = NLMSG_HDRLEN + 2;
+       nlh = nlh0 - 2;
+       /* Beware of unaligned access to nlh members. */
+       memmove(nlh, nlh0, sizeof(*nlh));
+       memcpy(NLMSG_DATA(nlh), "42", 2);
+
+       rc = sendto(fd, nlh, NLMSG_HDRLEN + 2, MSG_DONTWAIT, NULL, 0);
+       printf("sendto(%d, {{len=%u, type=NLMSG_DONE, flags=NLM_F_MULTI"
+              ", seq=0, pid=0}, \"42\"}, %u, MSG_DONTWAIT, NULL, 0) = %s\n",
+              fd, NLMSG_HDRLEN + 2, NLMSG_HDRLEN + 2, sprintrc(rc));
+
+       /* NLMSG_DONE message with enough room for an integer payload */
+       nlh = nlh0 - sizeof(num);
+       *nlh = (struct nlmsghdr) {
+               .nlmsg_len = NLMSG_HDRLEN + sizeof(num),
+               .nlmsg_type = NLMSG_DONE,
+               .nlmsg_flags = NLM_F_MULTI
+       };
+       memcpy(NLMSG_DATA(nlh), &num, sizeof(num));
 
        rc = sendto(fd, nlh, nlh->nlmsg_len, MSG_DONTWAIT, NULL, 0);
        printf("sendto(%d, {{len=%u, type=NLMSG_DONE, flags=NLM_F_MULTI"
               ", seq=0, pid=0}, %d}, %u, MSG_DONTWAIT, NULL, 0) = %s\n",
-              fd, nlh->nlmsg_len, nlh->nlmsg_len, total_len, sprintrc(rc));
+              fd, nlh->nlmsg_len, num, nlh->nlmsg_len, sprintrc(rc));
 }
 
 int main(void)