6.6-stable review patch. If anyone has any objections, please let me know.
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From: Alexei Starovoitov ast@kernel.org
[ Upstream commit c13339039891dbdfa6c1972f0483bd07f610b776 ]
When test_send_signal_kern__open_and_load() fails parent closes the pipe which cases ASSERT_EQ(read(pipe_p2c...)) to fail, but child continues and enters infinite loop, while parent is stuck in wait(NULL). Other error paths have similar issue, so kill the child before waiting on it.
The bug was discovered while compiling all of selftests with -O1 instead of -O2 which caused progs/test_send_signal_kern.c to fail to load.
Fixes: ab8b7f0cb358 ("tools/bpf: Add self tests for bpf_send_signal_thread()") Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Andrii Nakryiko andrii@kernel.org Acked-by: Eduard Zingerman eddyz87@gmail.com Link: https://lore.kernel.org/bpf/20251113171153.2583-1-alexei.starovoitov@gmail.c... Signed-off-by: Sasha Levin sashal@kernel.org --- tools/testing/selftests/bpf/prog_tests/send_signal.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/tools/testing/selftests/bpf/prog_tests/send_signal.c b/tools/testing/selftests/bpf/prog_tests/send_signal.c index 9adcda7f1fedc..61c9035000149 100644 --- a/tools/testing/selftests/bpf/prog_tests/send_signal.c +++ b/tools/testing/selftests/bpf/prog_tests/send_signal.c @@ -145,6 +145,11 @@ static void test_send_signal_common(struct perf_event_attr *attr, skel_open_load_failure: close(pipe_c2p[0]); close(pipe_p2c[1]); + /* + * Child is either about to exit cleanly or stuck in case of errors. + * Nudge it to exit. + */ + kill(pid, SIGKILL); wait(NULL); }