From 11e41444a3f6d854937672343a040607c219db0f Mon Sep 17 00:00:00 2001 From: Qingshuang Fu Date: Fri, 21 Aug 2026 11:14:42 +0800 Subject: [PATCH] selftests/net: check fork() return value in fin_ack_lat main() never checks fork() for failure. When fork() returns -1 (EAGAIN/ENOMEM/RLIMIT_NPROC), the !child_pid test is false and the process falls into server()'s infinite accept() loop with no client ever connecting, producing empty output. The wrapper script treats an empty log as a passing test, producing a false positive. Check fork() for failure with error(), as is done for every other syscall in this file. Signed-off-by: Qingshuang Fu Reviewed-by: Hangbin Liu Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260821031442.1124777-2-fffsqian@163.com Signed-off-by: Jakub Kicinski --- tools/testing/selftests/net/fin_ack_lat.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/testing/selftests/net/fin_ack_lat.c b/tools/testing/selftests/net/fin_ack_lat.c index 98044e6f9f43..4068f8e227cf 100644 --- a/tools/testing/selftests/net/fin_ack_lat.c +++ b/tools/testing/selftests/net/fin_ack_lat.c @@ -143,6 +143,8 @@ int main(int argc, char const *argv[]) fprintf(stderr, "server port: %d\n", ntohs(laddr.sin_port)); child_pid = fork(); + if (child_pid < 0) + error(-1, errno, "fork"); if (!child_pid) client(ntohs(laddr.sin_port)); else