[PATCH mptcp-next] selftests: mptcp: diag: drop nlh parameter of recv_nlmsg

[PATCH mptcp-next] selftests: mptcp: diag: drop nlh parameter of recv_nlmsg

[Geliang Tang]

From: Geliang Tang <tanggeliang@kylinos.cn>

It's strange that 'nlh' variable is set to NULL in get_mptcpinfo() and then
this NULL pointer is passed to recv_nlmsg(). In fact, this variable should
be defined in recv_nlmsg(), not get_mptcpinfo().

So this patch drops this useless 'nlh' parameter of recv_nlmsg() and define
'nlh' variable in recv_nlmsg().

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 tools/testing/selftests/net/mptcp/mptcp_diag.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/net/mptcp/mptcp_diag.c b/tools/testing/selftests/net/mptcp/mptcp_diag.c
index 284286c524cf..37d5015ad08c 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_diag.c
+++ b/tools/testing/selftests/net/mptcp/mptcp_diag.c
@@ -185,9 +185,10 @@ static void parse_nlmsg(struct nlmsghdr *nlh)
 	}
 }
 
-static void recv_nlmsg(int fd, struct nlmsghdr *nlh)
+static void recv_nlmsg(int fd)
 {
 	char rcv_buff[8192];
+	struct nlmsghdr *nlh = (struct nlmsghdr *)rcv_buff;
 	struct sockaddr_nl rcv_nladdr = {
 		.nl_family = AF_NETLINK
 	};
@@ -204,7 +205,6 @@ static void recv_nlmsg(int fd, struct nlmsghdr *nlh)
 	int len;
 
 	len = recvmsg(fd, &rcv_msg, 0);
-	nlh = (struct nlmsghdr *)rcv_buff;
 
 	while (NLMSG_OK(nlh, len)) {
 		if (nlh->nlmsg_type == NLMSG_DONE) {
@@ -225,7 +225,6 @@ static void recv_nlmsg(int fd, struct nlmsghdr *nlh)
 
 static void get_mptcpinfo(__u32 token)
 {
-	struct nlmsghdr *nlh = NULL;
 	int fd;
 
 	fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_SOCK_DIAG);
@@ -233,7 +232,7 @@ static void get_mptcpinfo(__u32 token)
 		die_perror("Netlink socket");
 
 	send_query(fd, token);
-	recv_nlmsg(fd, nlh);
+	recv_nlmsg(fd);
 
 	close(fd);
 }
-- 
2.43.0

Re: [PATCH mptcp-next] selftests: mptcp: diag: drop nlh parameter of recv_nlmsg

[MPTCP CI]

Hi Geliang,

Thank you for your modifications, that's great!

Our CI did some validations and here is its report:

- KVM Validation: normal: Success! ✅
- KVM Validation: debug: Success! ✅
- KVM Validation: btf-normal (only bpftest_all): Success! ✅
- KVM Validation: btf-debug (only bpftest_all): Success! ✅
- Task: https://github.com/multipath-tcp/mptcp_net-next/actions/runs/14304160762

Initiator: Patchew Applier
Commits: https://github.com/multipath-tcp/mptcp_net-next/commits/aead1761a001
Patchwork: https://patchwork.kernel.org/project/mptcp/list/?series=950398


If there are some issues, you can reproduce them using the same environment as
the one used by the CI thanks to a docker image, e.g.:

    $ cd [kernel source code]
    $ docker run -v "${PWD}:${PWD}:rw" -w "${PWD}" --privileged --rm -it \
        --pull always mptcp/mptcp-upstream-virtme-docker:latest \
        auto-normal

For more details:

    https://github.com/multipath-tcp/mptcp-upstream-virtme-docker


Please note that despite all the efforts that have been already done to have a
stable tests suite when executed on a public CI like here, it is possible some
reported issues are not due to your modifications. Still, do not hesitate to
help us improve that ;-)

Cheers,
MPTCP GH Action bot
Bot operated by Matthieu Baerts (NGI0 Core)

Re: [PATCH mptcp-next] selftests: mptcp: diag: drop nlh parameter of recv_nlmsg

[Matthieu Baerts]

Hi Geliang,

On 07/04/2025 09:53, Geliang Tang wrote:
> From: Geliang Tang <tanggeliang@kylinos.cn>
> 
> It's strange that 'nlh' variable is set to NULL in get_mptcpinfo() and then
> this NULL pointer is passed to recv_nlmsg(). In fact, this variable should
> be defined in recv_nlmsg(), not get_mptcpinfo().
> 
> So this patch drops this useless 'nlh' parameter of recv_nlmsg() and define
> 'nlh' variable in recv_nlmsg().

Indeed, that is better like that.

Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>

Cheers,
Matt
-- 
Sponsored by the NGI0 Core fund.

Re: [PATCH mptcp-next] selftests: mptcp: diag: drop nlh parameter of recv_nlmsg

[Matthieu Baerts]

Hi Geliang,

On 07/04/2025 09:53, Geliang Tang wrote:
> From: Geliang Tang <tanggeliang@kylinos.cn>
> 
> It's strange that 'nlh' variable is set to NULL in get_mptcpinfo() and then
> this NULL pointer is passed to recv_nlmsg(). In fact, this variable should
> be defined in recv_nlmsg(), not get_mptcpinfo().
> 
> So this patch drops this useless 'nlh' parameter of recv_nlmsg() and define
> 'nlh' variable in recv_nlmsg().

Now in our tree:

New patches for t/upstream:
- 65056576ab07: selftests: mptcp: diag: drop nlh parameter of recv_nlmsg
- Results: 244c301d3de6..d16892726caa (export)

Tests are now in progress:

- export:
https://github.com/multipath-tcp/mptcp_net-next/commit/5b28c8bf763dc38db8b1e81e3222a3a16e49bb36/checks

Cheers,
Matt
-- 
Sponsored by the NGI0 Core fund.