Re: [PATCH 04/10] unpack_loose_header(): fix infinite loop on broken zlib input

From: Junio C Hamano <gitster@pobox.com>
Date: Feb 26, 2025, 12:56 UTC
Message-ID: <xmqq34g0hnkr.fsf@gitster.g>
In-Reply-To: <20250225062958.GD1293961@coredump.intra.peff.net>

Jeff King <peff@peff.net> writes:

Show 12 quoted lines

> diff --git a/object-file.c b/object-file.c
> index 8c9295413b..5b2446bfc1 100644
> --- a/object-file.c
> +++ b/object-file.c
> @@ -1396,7 +1396,7 @@ enum unpack_loose_header_result unpack_loose_header(git_zstream *stream,
>  		strbuf_add(header, buffer, stream->next_out - (unsigned char *)buffer);
>  		if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
>  			return 0;
> -	} while (status != Z_STREAM_END);
> +	} while (status == Z_OK);
>  	return ULHR_BAD;
>  }

Ah, fond memories. I do recall we had very similar bugs whose correct solution was "instead of stopping with Z_something, just write your loop to keep ging while you get Z_OK" every time we encountered them.