Linux 5.1 implemented 64-bit time types and related syscalls to address the Y2038 problem generally across archs. Userspace handling of Y2038 varies with the libc however. While musl libc uses 64-bit time across all 32-bit and 64-bit platforms, GNU glibc uses 64-bit time on 64-bit platforms but defaults to 32-bit time on 32-bit platforms unless they "opt-in" to 64-bit time or explicitly use 64-bit syscalls and time structures.
One specific area is the standard setsockopt() call, SO_TIMESTAMPNS option used for timestamping, and the related output 'struct timespec'. GNU glibc defaults as above, also exposing the SO_TIMESTAMPNS_NEW flag to explicitly use a 64-bit call and 'struct __kernel_timespec'. Since these are not exposed or needed with musl libc, their use in tc_redirect.c leads to compile errors building for mips64el/musl:
tc_redirect.c: In function 'rcv_tstamp': tc_redirect.c:425:32: error: 'SO_TIMESTAMPNS_NEW' undeclared (first use in this function); did you mean 'SO_TIMESTAMPNS'? 425 | cmsg->cmsg_type == SO_TIMESTAMPNS_NEW) | ^~~~~~~~~~~~~~~~~~ | SO_TIMESTAMPNS tc_redirect.c:425:32: note: each undeclared identifier is reported only once for each function it appears in tc_redirect.c: In function 'test_inet_dtime': tc_redirect.c:491:49: error: 'SO_TIMESTAMPNS_NEW' undeclared (first use in this function); did you mean 'SO_TIMESTAMPNS'? 491 | err = setsockopt(listen_fd, SOL_SOCKET, SO_TIMESTAMPNS_NEW, | ^~~~~~~~~~~~~~~~~~ | SO_TIMESTAMPNS
However, using SO_TIMESTAMPNS_NEW isn't strictly needed, nor is Y2038 being explicitly tested. The timestamp checks in tc_redirect.c are simple: the packet receive timestamp is non-zero and processed/handled in less than 5 seconds.
Switch to using the standard setsockopt() call and SO_TIMESTAMPNS option to ensure compatibility across glibc and musl libc. In the worst-case, there is a 5-second window 14 years from now where tc_redirect tests may fail on 32-bit systems. However, we should reasonably expect glibc to adopt a 64-bit mandate rather than the current "opt-in" policy before the Y2038 roll-over.
Fixes: ce6f6cffaeaa ("selftests/bpf: Wait for the netstamp_needed_key static key to be turned on") Fixes: c803475fd8dd ("bpf: selftests: test skb->tstamp in redirect_neigh") Signed-off-by: Tony Ambardar tony.ambardar@gmail.com --- tools/testing/selftests/bpf/prog_tests/tc_redirect.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/tc_redirect.c b/tools/testing/selftests/bpf/prog_tests/tc_redirect.c index 327d51f59142..53b8ffc943dc 100644 --- a/tools/testing/selftests/bpf/prog_tests/tc_redirect.c +++ b/tools/testing/selftests/bpf/prog_tests/tc_redirect.c @@ -471,7 +471,7 @@ static int set_forwarding(bool enable)
static int __rcv_tstamp(int fd, const char *expected, size_t s, __u64 *tstamp) { - struct __kernel_timespec pkt_ts = {}; + struct timespec pkt_ts = {}; char ctl[CMSG_SPACE(sizeof(pkt_ts))]; struct timespec now_ts; struct msghdr msg = {}; @@ -495,7 +495,7 @@ static int __rcv_tstamp(int fd, const char *expected, size_t s, __u64 *tstamp)
cmsg = CMSG_FIRSTHDR(&msg); if (cmsg && cmsg->cmsg_level == SOL_SOCKET && - cmsg->cmsg_type == SO_TIMESTAMPNS_NEW) + cmsg->cmsg_type == SO_TIMESTAMPNS) memcpy(&pkt_ts, CMSG_DATA(cmsg), sizeof(pkt_ts));
pkt_ns = pkt_ts.tv_sec * NSEC_PER_SEC + pkt_ts.tv_nsec; @@ -537,9 +537,9 @@ static int wait_netstamp_needed_key(void) if (!ASSERT_GE(srv_fd, 0, "start_server")) goto done;
- err = setsockopt(srv_fd, SOL_SOCKET, SO_TIMESTAMPNS_NEW, + err = setsockopt(srv_fd, SOL_SOCKET, SO_TIMESTAMPNS, &opt, sizeof(opt)); - if (!ASSERT_OK(err, "setsockopt(SO_TIMESTAMPNS_NEW)")) + if (!ASSERT_OK(err, "setsockopt(SO_TIMESTAMPNS)")) goto done;
cli_fd = connect_to_fd(srv_fd, TIMEOUT_MILLIS); @@ -621,9 +621,9 @@ static void test_inet_dtime(int family, int type, const char *addr, __u16 port) return;
/* Ensure the kernel puts the (rcv) timestamp for all skb */ - err = setsockopt(listen_fd, SOL_SOCKET, SO_TIMESTAMPNS_NEW, + err = setsockopt(listen_fd, SOL_SOCKET, SO_TIMESTAMPNS, &opt, sizeof(opt)); - if (!ASSERT_OK(err, "setsockopt(SO_TIMESTAMPNS_NEW)")) + if (!ASSERT_OK(err, "setsockopt(SO_TIMESTAMPNS)")) goto done;
if (type == SOCK_STREAM) {