Selftests are supposed to run on any kernels, including the old ones not supporting all MPTCP features. One of them is the getsockopt(SOL_MPTCP) to get info about the MPTCP connections introduced by commit 55c42fa7fa33 ("mptcp: add MPTCP_INFO getsockopt") and the following ones. We cannot guess in advance which sizes the kernel will returned: older kernel can returned smaller sizes, e.g. recently the tcp_info structure has been modified in commit 71fc704768f6 ("tcp: add rcv_wnd and plb_rehash to TCP_INFO") where a new field has been added. The userspace can also expect a smaller size if it is compiled with old uAPI kernel headers. So for these sizes, we can only check if they are above a certain threshold, 0 for the moment. We can also only compared sizes with the ones set by the kernel. Link: https://github.com/multipath-tcp/mptcp_net-next/issues/368 Fixes: ce9979129a0b ("selftests: mptcp: add mptcp getsockopt test cases") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Matthieu Baerts <matthieu.baerts@xxxxxxxxxxxx> --- tools/testing/selftests/net/mptcp/mptcp_sockopt.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c index ae61f39556ca..b35148edbf02 100644 --- a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c +++ b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c @@ -87,6 +87,10 @@ struct so_state { uint64_t tcpi_rcv_delta; }; +#ifndef MIN +#define MIN(a, b) ((a) < (b) ? (a) : (b)) +#endif + static void die_perror(const char *msg) { perror(msg); @@ -349,13 +353,14 @@ static void do_getsockopt_tcp_info(struct so_state *s, int fd, size_t r, size_t xerror("getsockopt MPTCP_TCPINFO (tries %d, %m)"); assert(olen <= sizeof(ti)); - assert(ti.d.size_user == ti.d.size_kernel); - assert(ti.d.size_user == sizeof(struct tcp_info)); + assert(ti.d.size_kernel > 0); + assert(ti.d.size_user == + MIN(ti.d.size_kernel, sizeof(struct tcp_info))); assert(ti.d.num_subflows == 1); assert(olen > (socklen_t)sizeof(struct mptcp_subflow_data)); olen -= sizeof(struct mptcp_subflow_data); - assert(olen == sizeof(struct tcp_info)); + assert(olen == ti.d.size_user); if (ti.ti[0].tcpi_bytes_sent == w && ti.ti[0].tcpi_bytes_received == r) @@ -401,13 +406,14 @@ static void do_getsockopt_subflow_addrs(int fd) die_perror("getsockopt MPTCP_SUBFLOW_ADDRS"); assert(olen <= sizeof(addrs)); - assert(addrs.d.size_user == addrs.d.size_kernel); - assert(addrs.d.size_user == sizeof(struct mptcp_subflow_addrs)); + assert(addrs.d.size_kernel > 0); + assert(addrs.d.size_user == + MIN(addrs.d.size_kernel, sizeof(struct mptcp_subflow_addrs))); assert(addrs.d.num_subflows == 1); assert(olen > (socklen_t)sizeof(struct mptcp_subflow_data)); olen -= sizeof(struct mptcp_subflow_data); - assert(olen == sizeof(struct mptcp_subflow_addrs)); + assert(olen == addrs.d.size_user); llen = sizeof(local); ret = getsockname(fd, (struct sockaddr *)&local, &llen); -- 2.40.1