From 060fd1035880dd466607d1c279ca913dd1f96916 Mon Sep 17 00:00:00 2001 From: Andrei Matei Date: Sat, 30 Jan 2021 17:01:50 -0500 Subject: [PATCH] selftest/bpf: Testing for multiple logs on REJECT This patch adds support to verifier tests to check for a succession of verifier log messages on program load failure. This makes the errstr field work uniformly across REJECT and VERBOSE_ACCEPT checks. This patch also increases the maximum size of a message in the series of messages to test from 80 chars to 200 chars. This is in order to keep existing tests working, which sometimes test for messages larger than 80 chars (which was accepted in the REJECT case, when testing for a single message, but not in the VERBOSE_ACCEPT case, when testing for possibly multiple messages). And example of such a long, checked message is in bounds.c: "R1 has unknown scalar with mixed signed bounds, pointer arithmetic with it prohibited for !root" Signed-off-by: Andrei Matei Signed-off-by: Daniel Borkmann Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20210130220150.59305-1-andreimatei1@gmail.com --- tools/testing/selftests/bpf/test_verifier.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c index 59bfa6201d1d..58b5a349d3ba 100644 --- a/tools/testing/selftests/bpf/test_verifier.c +++ b/tools/testing/selftests/bpf/test_verifier.c @@ -88,6 +88,10 @@ struct bpf_test { int fixup_map_event_output[MAX_FIXUPS]; int fixup_map_reuseport_array[MAX_FIXUPS]; int fixup_map_ringbuf[MAX_FIXUPS]; + /* Expected verifier log output for result REJECT or VERBOSE_ACCEPT. + * Can be a tab-separated sequence of expected strings. An empty string + * means no log verification. + */ const char *errstr; const char *errstr_unpriv; uint32_t insn_processed; @@ -995,13 +999,19 @@ static int do_prog_test_run(int fd_prog, bool unpriv, uint32_t expected_val, return 0; } +/* Returns true if every part of exp (tab-separated) appears in log, in order. + * + * If exp is an empty string, returns true. + */ static bool cmp_str_seq(const char *log, const char *exp) { - char needle[80]; + char needle[200]; const char *p, *q; int len; do { + if (!strlen(exp)) + break; p = strchr(exp, '\t'); if (!p) p = exp + strlen(exp); @@ -1015,7 +1025,7 @@ static bool cmp_str_seq(const char *log, const char *exp) needle[len] = 0; q = strstr(log, needle); if (!q) { - printf("FAIL\nUnexpected verifier log in successful load!\n" + printf("FAIL\nUnexpected verifier log!\n" "EXP: %s\nRES:\n", needle); return false; } @@ -1130,7 +1140,7 @@ static void do_test_single(struct bpf_test *test, bool unpriv, printf("FAIL\nUnexpected success to load!\n"); goto fail_log; } - if (!expected_err || !strstr(bpf_vlog, expected_err)) { + if (!expected_err || !cmp_str_seq(bpf_vlog, expected_err)) { printf("FAIL\nUnexpected error message!\n\tEXP: %s\n\tRES: %s\n", expected_err, bpf_vlog); goto fail_log;