From 3324dd8f267cb59cdd42ac33727b6844921d5017 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Wed, 29 Jun 2016 16:14:54 +0200 Subject: commit -S: avoid invalid pointer with empty message While it is not recommended, fsck.c says: Not having a body is not a crime [...] ... which means that we cannot assume that the commit buffer contains an empty line to separate header from body. A commit object with only a header without any body, not even without a blank line after the header, is valid. So let's tread carefully here. strstr("\n\n") may find nothing and return NULL. Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano --- commit.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/commit.c b/commit.c index d1810c940..ee7f0cb02 100644 --- a/commit.c +++ b/commit.c @@ -1092,9 +1092,14 @@ static int do_sign_commit(struct strbuf *buf, const char *keyid) { struct strbuf sig = STRBUF_INIT; int inspos, copypos; + const char *eoh; /* find the end of the header */ - inspos = strstr(buf->buf, "\n\n") - buf->buf + 1; + eoh = strstr(buf->buf, "\n\n"); + if (!eoh) + inspos = buf->len; + else + inspos = eoh - buf->buf + 1; if (!keyid || !*keyid) keyid = get_signing_key(); -- cgit v1.2.1