From e76a014334a6d46a9c21356afa25aa5b81566540 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= Date: Thu, 6 Jul 2023 16:22:28 +0200 Subject: [PATCH] selftests/bpf: Bump and validate MAX_SYMS MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit BPF tests that load /proc/kallsyms, e.g. bpf_cookie, will perform a buffer overrun if the number of syms on the system is larger than MAX_SYMS. Bump the MAX_SYMS to 400000, and add a runtime check that bails out if the maximum is reached. Signed-off-by: Björn Töpel Signed-off-by: Andrii Nakryiko Acked-by: Stanislav Fomichev Link: https://lore.kernel.org/bpf/20230706142228.1128452-1-bjorn@kernel.org --- tools/testing/selftests/bpf/trace_helpers.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/bpf/trace_helpers.c b/tools/testing/selftests/bpf/trace_helpers.c index 9b070cdf44ac..f83d9f65c65b 100644 --- a/tools/testing/selftests/bpf/trace_helpers.c +++ b/tools/testing/selftests/bpf/trace_helpers.c @@ -18,7 +18,7 @@ #define TRACEFS_PIPE "/sys/kernel/tracing/trace_pipe" #define DEBUGFS_PIPE "/sys/kernel/debug/tracing/trace_pipe" -#define MAX_SYMS 300000 +#define MAX_SYMS 400000 static struct ksym syms[MAX_SYMS]; static int sym_cnt; @@ -46,6 +46,9 @@ int load_kallsyms_refresh(void) break; if (!addr) continue; + if (i >= MAX_SYMS) + return -EFBIG; + syms[i].addr = (long) addr; syms[i].name = strdup(func); i++;