kernel/tools/testing/selftests/bpf/test_progs.c, branch master

selftests/bpf: Don't override SIGSEGV handler with ASAN

2026-02-24T16:19:49Z

test_progs has custom SIGSEGV handler, which interferes with the address sanitizer [1]. Add an #ifndef to avoid this. Additionally, declare an __asan_on_error() to dump the test logs in the same way it happens in the custom SIGSEGV handler. [1] https://lore.kernel.org/bpf/73d832948b01dbc0ebc60d85574bdf8537f3a810.camel@gmail.com/ Acked-by: Mykyta Yatsenko Acked-by: Eduard Zingerman Signed-off-by: Ihor Solodrai Link: https://lore.kernel.org/r/20260223191118.655185-3-ihor.solodrai@linux.dev Signed-off-by: Alexei Starovoitov

selftests/bpf: Replace strncpy() with strscpy()

2026-02-24T16:19:33Z

strncpy() does not guarantee NULL-termination and is considered deprecated [1]. Replace strncpy() calls with strscpy(). [1] https://docs.kernel.org/process/deprecated.html#strncpy-on-nul-terminated-strings Signed-off-by: Ihor Solodrai Link: https://lore.kernel.org/r/20260223190736.649171-4-ihor.solodrai@linux.dev Signed-off-by: Alexei Starovoitov

selftests/bpf: Enable signature verification for some lskel tests

2025-09-23T02:17:55Z

The test harness uses the verify_sig_setup.sh to generate the required key material for program signing. Generate key material for signing LSKEL some lskel programs and use xxd to convert the verification certificate into a C header file. Finally, update the main test runner to load this certificate into the session keyring via the add_key() syscall before executing any tests. Use the session keyring in the tests with signed programs. Signed-off-by: KP Singh Link: https://lore.kernel.org/r/20250921160120.9711-6-kpsingh@kernel.org Signed-off-by: Alexei Starovoitov

selftests/bpf: Sanitize pointer prior fclose()

2025-03-20T17:35:07Z

There are scenarios where env.{sub,}test_state->stdout_saved, can be NULL, e.g. sometimes when the watchdog timeout kicks in, or if the open_memstream syscall is not available. Avoid crashing test_progs by adding an explicit NULL check prior the fclose() call. Signed-off-by: Björn Töpel Signed-off-by: Andrii Nakryiko Acked-by: Jiri Olsa Link: https://lore.kernel.org/bpf/20250318081648.122523-1-bjorn@kernel.org

selftests/bpf: Fix dangling stdout seen by traffic monitor thread

2025-03-15T18:48:57Z

Traffic monitor thread may see dangling stdout as the main thread closes and reassigns stdout without protection. This happens when the main thread finishes one subtest and moves to another one in the same netns_new() scope. The issue can be reproduced by running test_progs repeatedly with traffic monitor enabled: for ((i=1;i<=100;i++)); do ./test_progs -a flow_dissector_skb* -m '*' done For restoring stdout in crash_handler(), since it does not really care about closing stdout, simlpy flush stdout and restore it to the original one. Then, Fix the issue by consolidating stdio_restore_cleanup() and stdio_restore(), and protecting the use/close/assignment of stdout with a lock. The locking in the main thread is always performed regradless of whether traffic monitor is running or not for simplicity. It won't have any side-effect. Signed-off-by: Amery Hung Signed-off-by: Martin KaFai Lau Acked-by: Eduard Zingerman Link: https://patch.msgid.link/20250305182057.2802606-3-ameryhung@gmail.com Signed-off-by: Alexei Starovoitov

selftests/bpf: Clean up call sites of stdio_restore()

2025-03-15T18:48:57Z

reset_affinity() and save_ns() are only called in run_one_test(). There is no need to call stdio_restore() in reset_affinity() and save_ns() if stdio_restore() is moved right after a test finishes in run_one_test(). Also remove an unnecessary check of env.stdout_saved in crash_handler() by moving env.stdout_saved assignment to the beginning of main(). Signed-off-by: Amery Hung Signed-off-by: Martin KaFai Lau Acked-by: Eduard Zingerman Link: https://patch.msgid.link/20250305182057.2802606-1-ameryhung@gmail.com Signed-off-by: Alexei Starovoitov

selftests/bpf: Optionally open a dedicated namespace to run test in it

2025-02-19T17:46:02Z

Some tests are serialized to prevent interference with others. Open a dedicated network namespace when a test name starts with 'ns_' to allow more test parallelization. Use the test name as namespace name to avoid conflict between namespaces. Signed-off-by: Bastien Curutchet (eBPF Foundation) Link: https://lore.kernel.org/r/20250219-b4-tc_links-v2-2-14504db136b7@bootlin.com Signed-off-by: Alexei Starovoitov

selftests/bpf: add a macro to compare raw memory

2024-12-02T16:41:15Z

We sometimes need to compare whole structures in an assert. It is possible to use the existing macros on each field, but when the whole structure has to be checked, it is more convenient to simply compare the whole structure memory Add a dedicated assert macro, ASSERT_MEMEQ, to allow bare memory comparision The output generated by this new macro looks like the following: [...] run_tests_skb_less:FAIL:returned flow keys unexpected memory mismatch actual: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 expected: 0E 00 3E 00 DD 86 01 01 00 06 86 DD 50 00 90 1F 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 [...] Acked-by: Stanislav Fomichev Signed-off-by: Alexis Lothoré (eBPF Foundation) Link: https://lore.kernel.org/r/20241120-flow_dissector-v3-1-45b46494f937@bootlin.com Signed-off-by: Alexei Starovoitov

selftests/bpf: watchdog timer for test_progs

2024-11-12T21:53:27Z

This commit provides a watchdog timer that sets a limit of how long a single sub-test could run: - if sub-test runs for 10 seconds, the name of the test is printed (currently the name of the test is printed only after it finishes); - if sub-test runs for 120 seconds, the running thread is terminated with SIGSEGV (to trigger crash_handler() and get a stack trace). Specifically: - the timer is armed on each call to run_one_test(); - re-armed at each call to test__start_subtest(); - is stopped when exiting run_one_test(). Default timeout could be overridden using '-w' or '--watchdog-timeout' options. Value 0 can be used to turn the timer off. Here is an example execution: $ ./ssh-exec.sh ./test_progs -w 5 -t \ send_signal/send_signal_perf_thread_remote,send_signal/send_signal_nmi_thread_remote WATCHDOG: test case send_signal/send_signal_nmi_thread_remote executes for 5 seconds, terminating with SIGSEGV Caught signal #11! Stack trace: ./test_progs(crash_handler+0x1f)[0x9049ef] /lib64/libc.so.6(+0x40d00)[0x7f1f1184fd00] /lib64/libc.so.6(read+0x4a)[0x7f1f1191cc4a] ./test_progs[0x720dd3] ./test_progs[0x71ef7a] ./test_progs(test_send_signal+0x1db)[0x71edeb] ./test_progs[0x9066c5] ./test_progs(main+0x5ed)[0x9054ad] /lib64/libc.so.6(+0x2a088)[0x7f1f11839088] /lib64/libc.so.6(__libc_start_main+0x8b)[0x7f1f1183914b] ./test_progs(_start+0x25)[0x527385] #292 send_signal:FAIL test_send_signal_common:PASS:reading pipe 0 nsec test_send_signal_common:PASS:reading pipe error: size 0 0 nsec test_send_signal_common:PASS:incorrect result 0 nsec test_send_signal_common:PASS:pipe_write 0 nsec test_send_signal_common:PASS:setpriority 0 nsec Timer is implemented using timer_{create,start} librt API. Internally librt uses pthreads for SIGEV_THREAD timers, so this change adds a background timer thread to the test process. Because of this a few checks in tests 'bpf_iter' and 'iters' need an update to account for an extra thread. For parallelized scenario the watchdog is also created for each worker fork. If one of the workers gets stuck, it would be terminated by a watchdog. In theory, this might lead to a scenario when all worker threads are exhausted, however this should not be a problem for server_main(), as it would exit with some of the tests not run. Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20241112110906.3045278-2-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov

selftests/bpf: Fix backtrace printing for selftests crashes

2024-10-08T03:30:13Z

test_progs uses glibc specific functions backtrace() and backtrace_symbols_fd() to print backtrace in case of SIGSEGV. Recent commit (see fixes) updated test_progs.c to define stub versions of the same functions with attriubte "weak" in order to allow linking test_progs against musl libc. Unfortunately this broke the backtrace handling for glibc builds. As it turns out, glibc defines backtrace() and backtrace_symbols_fd() as weak: $ llvm-readelf --symbols /lib64/libc.so.6 \ | grep -P '( backtrace_symbols_fd| backtrace)$' 4910: 0000000000126b40 161 FUNC WEAK DEFAULT 16 backtrace 6843: 0000000000126f90 852 FUNC WEAK DEFAULT 16 backtrace_symbols_fd So does test_progs: $ llvm-readelf --symbols test_progs \ | grep -P '( backtrace_symbols_fd| backtrace)$' 2891: 00000000006ad190 15 FUNC WEAK DEFAULT 13 backtrace 11215: 00000000006ad1a0 41 FUNC WEAK DEFAULT 13 backtrace_symbols_fd In such situation dynamic linker is not obliged to favour glibc implementation over the one defined in test_progs. Compiling with the following simple modification to test_progs.c demonstrates the issue: $ git diff ... \--- a/tools/testing/selftests/bpf/test_progs.c \+++ b/tools/testing/selftests/bpf/test_progs.c \@@ -1817,6 +1817,7 @@ int main(int argc, char **argv) if (err) return err; + *(int *)0xdeadbeef = 42; err = cd_flavor_subdir(argv[0]); if (err) return err; $ ./test_progs [0]: Caught signal #11! Stack trace: Segmentation fault (core dumped) Resolve this by hiding stub definitions behind __GLIBC__ macro check instead of using "weak" attribute. Fixes: c9a83e76b5a9 ("selftests/bpf: Fix compile if backtrace support missing in libc") Signed-off-by: Eduard Zingerman Signed-off-by: Andrii Nakryiko Tested-by: Tony Ambardar Reviewed-by: Tony Ambardar Acked-by: Daniel Xu Link: https://lore.kernel.org/bpf/20241003210307.3847907-1-eddyz87@gmail.com