From f3612acb9302fc9332958b77c5ca5fc05cacb029 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Fri, 12 Jun 2015 17:28:08 -0400 Subject: [PATCH] pkt-line: simplify starts_with checks in packet tracing We carefully check that our pkt buffer has enough characters before seeing if it starts with "PACK". The intent is to avoid reading random memory if we get a short buffer like "PAC". However, we know that the traced packets are always NUL-terminated. They come from one of these sources: 1. A string literal. 2. `format_packet`, which uses a strbuf. 3. `packet_read`, which defensively NUL-terminates what we read. We can therefore drop the length checks, as we know we will hit the trailing NUL if we have a short input. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- pkt-line.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/pkt-line.c b/pkt-line.c index 187a2293e7..0477d2eefe 100644 --- a/pkt-line.c +++ b/pkt-line.c @@ -24,8 +24,7 @@ static void packet_trace(const char *buf, unsigned int len, int write) strbuf_addf(&out, "packet: %12s%c ", packet_trace_prefix, write ? '>' : '<'); - if ((len >= 4 && starts_with(buf, "PACK")) || - (len >= 5 && starts_with(buf+1, "PACK"))) { + if (starts_with(buf, "PACK") || starts_with(buf + 1, "PACK")) { strbuf_addstr(&out, "PACK ..."); trace_disable(&trace_packet); }