From: JingPiao Chen <chenjingpiao@gmail.com>
Date: Fri, 5 May 2017 10:21:17 +0000 (+0800)
Subject: netlink: decode NLMSG_DONE messages
X-Git-Tag: v4.18~136
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=852046ce0e456e5e411d7d93dcc5e4a44bae7d30;p=strace

netlink: decode NLMSG_DONE messages

* netlink.c (decode_payload): Decode NLMSG_DONE messages.
* tests/netlink_protocol.c (test_nlmsg_done): New function
for checking decoding of NLMSG_DONE messages.
(main): Use it.
---

diff --git a/netlink.c b/netlink.c
index 678343c8..daaa745f 100644
--- a/netlink.c
+++ b/netlink.c
@@ -120,6 +120,12 @@ decode_payload(struct tcb *const tcp,
 	if (nlmsghdr->nlmsg_type == NLMSG_ERROR) {
 		decode_nlmsgerr(tcp, addr, len);
 		return;
+	} else if (nlmsghdr->nlmsg_type == NLMSG_DONE && len == sizeof(int)) {
+		int num;
+
+		if (!umove_or_printaddr(tcp, addr, &num))
+			tprintf("%d", num);
+		return;
 	}
 
 	printstrn(tcp, addr, len);
diff --git a/tests/netlink_protocol.c b/tests/netlink_protocol.c
index 35f954fd..121c83d0 100644
--- a/tests/netlink_protocol.c
+++ b/tests/netlink_protocol.c
@@ -314,6 +314,42 @@ test_nlmsgerr(const int fd)
 	       nlh->nlmsg_len, sprintrc(rc));
 }
 
+static void
+test_nlmsg_done(const int fd)
+{
+	struct nlmsghdr *nlh;
+	int total_len;
+	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
+	long rc;
+
+	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;
+
+	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}, %p}, %u, MSG_DONTWAIT, NULL, 0) = %s\n",
+	       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));
+
+	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));
+}
+
 int main(void)
 {
 	struct sockaddr_nl addr;
@@ -343,6 +379,7 @@ int main(void)
 
 	send_query(fd);
 	test_nlmsgerr(fd);
+	test_nlmsg_done(fd);
 
 	printf("+++ exited with 0 +++\n");