From 193a983c5bc4c62f66d62a9a6f9084cf3f2a0db2 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Tue, 25 Aug 2020 21:21:11 +0200 Subject: tools resolve_btfids: Add size check to get_id function To make sure we don't crash on malformed symbols. Signed-off-by: Jiri Olsa Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200825192124.710397-2-jolsa@kernel.org --- tools/bpf/resolve_btfids/main.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'tools/bpf') diff --git a/tools/bpf/resolve_btfids/main.c b/tools/bpf/resolve_btfids/main.c index 4d9ecb975862..35a172d3d80d 100644 --- a/tools/bpf/resolve_btfids/main.c +++ b/tools/bpf/resolve_btfids/main.c @@ -199,9 +199,16 @@ static char *get_id(const char *prefix_end) /* * __BTF_ID__func__vfs_truncate__0 * prefix_end = ^ + * pos = ^ */ - char *p, *id = strdup(prefix_end + sizeof("__") - 1); + int len = strlen(prefix_end); + int pos = sizeof("__") - 1; + char *p, *id; + if (pos >= len) + return NULL; + + id = strdup(prefix_end + pos); if (id) { /* * __BTF_ID__func__vfs_truncate__0 -- cgit v1.2.3