@matheusbsbs / matheus-bagliano / commits / b66b507292

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 <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Jeff King committed Oct 19, 2017 at 16:31 UTC b66b5072921fb706f1e9352f471098c988b0ca39

1 file changed +1 -1

diff.c

+1 -1

@@ -782,7 +782,7 @@ static unsigned get_string_hash(struct emitted_diff_symbol *es, struct diff_opti

782 strbuf_reset(&sb);

783 while (ae > ap && isspace(ae[-1]))

784 ae--;

785 - while ((c = next_byte(&ap, &ae, o)) > 0)

785 + while ((c = next_byte(&ap, &ae, o)) >= 0)

786 strbuf_addch(&sb, c);

787

788 return memhash(sb.buf, sb.len);