[PATCH bpf-next v2 2/8] selftests/bpf: Fix arg parsing in veristat, test_progs
From: Tony Ambardar <hidden>
Date: 2024-07-29 09:24:48
Also in:
bpf, linux-kselftest
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [selftests] (test runners & infrastructure), kernel selftest framework, the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Shuah Khan, Shuah Khan, Linus Torvalds
Current code parses arguments with strtok_r() using a construct like
char *state = NULL;
while ((next = strtok_r(state ? NULL : input, ",", &state))) {
...
}
where logic assumes the 'state' var can distinguish between first and
subsequent strtok_r() calls, and adjusts parameters accordingly. However,
'state' is strictly internal context for strtok_r() and no such assumptions
are supported in the man page. Moreover, the exact behaviour of 'state'
depends on the libc implementation, making the above code fragile.
Indeed, invoking "./test_progs -t <test_name>" on mips64el/musl will hang,
with the above code in an infinite loop.
Similarly, we see strange behaviour running 'veristat' on mips64el/musl:
$ ./veristat -e file,prog,verdict,insns -C two-ok add-failure
Can't specify more than 9 stats
Rewrite code using a counter to distinguish between strtok_r() calls.
Fixes: 61ddff373ffa ("selftests/bpf: Improve by-name subtest selection logic in prog_tests")
Fixes: 394169b079b5 ("selftests/bpf: add comparison mode to veristat")
Fixes: c8bc5e050976 ("selftests/bpf: Add veristat tool for mass-verifying BPF object files")
Signed-off-by: Tony Ambardar <redacted>
---
tools/testing/selftests/bpf/testing_helpers.c | 4 ++--
tools/testing/selftests/bpf/veristat.c | 8 ++++----
2 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/tools/testing/selftests/bpf/testing_helpers.c b/tools/testing/selftests/bpf/testing_helpers.c
index ac7c66f4fc7b..c217e12bd9da 100644
--- a/tools/testing/selftests/bpf/testing_helpers.c
+++ b/tools/testing/selftests/bpf/testing_helpers.c@@ -221,13 +221,13 @@ int parse_test_list(const char *s, bool is_glob_pattern) { char *input, *state = NULL, *test_spec; - int err = 0; + int err = 0, cnt = 0; input = strdup(s); if (!input) return -ENOMEM; - while ((test_spec = strtok_r(state ? NULL : input, ",", &state))) { + while ((test_spec = strtok_r(cnt++ ? NULL : input, ",", &state))) { err = insert_test(set, test_spec, is_glob_pattern); if (err) break;
diff --git a/tools/testing/selftests/bpf/veristat.c b/tools/testing/selftests/bpf/veristat.c
index 11ec1190d582..1ec5c4c47235 100644
--- a/tools/testing/selftests/bpf/veristat.c
+++ b/tools/testing/selftests/bpf/veristat.c@@ -785,13 +785,13 @@ static int parse_stat(const char *stat_name, struct stat_specs *specs) static int parse_stats(const char *stats_str, struct stat_specs *specs) { char *input, *state = NULL, *next; - int err; + int err, cnt = 0; input = strdup(stats_str); if (!input) return -ENOMEM; - while ((next = strtok_r(state ? NULL : input, ",", &state))) { + while ((next = strtok_r(cnt++ ? NULL : input, ",", &state))) { err = parse_stat(next, specs); if (err) { free(input);
@@ -1495,7 +1495,7 @@ static int parse_stats_csv(const char *filename, struct stat_specs *specs, while (fgets(line, sizeof(line), f)) { char *input = line, *state = NULL, *next; struct verif_stats *st = NULL; - int col = 0; + int col = 0, cnt = 0; if (!header) { void *tmp;
@@ -1513,7 +1513,7 @@ static int parse_stats_csv(const char *filename, struct stat_specs *specs, *stat_cntp += 1; } - while ((next = strtok_r(state ? NULL : input, ",\n", &state))) { + while ((next = strtok_r(cnt++ ? NULL : input, ",\n", &state))) { if (header) { /* for the first line, set up spec stats */ err = parse_stat(next, specs);
--
2.34.1