From b66b5072921fb706f1e9352f471098c988b0ca39 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Thu, 19 Oct 2017 16:31:20 -0400 Subject: [PATCH] diff: handle NULs in get_string_hash() For computing moved lines, we feed the characters of each line into a hash. When we've been asked to ignore whitespace, then we pick each character using next_byte(), which returns -1 on end-of-string, which it determines using the start/end pointers we feed it. However our check of its return value treats "0" the same as "-1", meaning we'd quit if the string has an embedded NUL. This is unlikely to ever come up in practice since our line boundaries generally come from calling strlen() in the first place. But it was a bit surprising to me as a reader of the next_byte() code. And it's possible that we may one day feed this function with more exotic input, which otherwise works with arbitrary ptr/len pairs. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- diff.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/diff.c b/diff.c index 09081a207c..c4a669ffa8 100644 --- a/diff.c +++ b/diff.c @@ -782,7 +782,7 @@ static unsigned get_string_hash(struct emitted_diff_symbol *es, struct diff_opti strbuf_reset(&sb); while (ae > ap && isspace(ae[-1])) ae--; - while ((c = next_byte(&ap, &ae, o)) > 0) + while ((c = next_byte(&ap, &ae, o)) >= 0) strbuf_addch(&sb, c); return memhash(sb.buf, sb.len); -- 2.32.0.93.g670b81a890