From: Matthieu Baerts matthieu.baerts@tessares.net
commit 8dee6ca2ac1e5630a7bb6a98bc0b686916fc2000 upstream.
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@vger.kernel.org Signed-off-by: Matthieu Baerts matthieu.baerts@tessares.net Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/testing/selftests/net/mptcp/mptcp_sockopt.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-)
--- 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(struc 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( 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);