[PATCH v3 12/17] object-file.c: return -2 on "header too long" in unpack_loose_header()
- From
Ævar Arnfjörð Bjarmason <avarab@gmail.com>
- Date
- May 20, 2021, 11:23 UTC
- Message-ID
- <patch-12.17-77f2cd439c-20210520T111610Z-avarab@gmail.com>
- In-Reply-To
- <cover-00.17-0000000000-20210520T111610Z-avarab@gmail.com>
Split up the return code for "header too long" from the generic negative return value unpack_loose_header() returns, and report via error() if we exceed MAX_HEADER_LEN.
As a test added earlier in this series in t1006-cat-file.sh shows we'll correctly emit zlib errors from zlib.c already in this case, so we have no need to carry those return codes further down the stack. Let's instead just return -2 saying we ran into the MAX_HEADER_LEN limit, or other negative values for "unable to unpack <OID> header".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> --- object-file.c | 15 ++++++++++----- object-store.h | 6 ++++-- t/t1006-cat-file.sh | 2 +- 3 files changed, 15 insertions(+), 8 deletions(-)
diff --git a/object-file.c b/object-file.c index d4bdf86657..7623ada1aa 100644 --- a/object-file.c +++ b/object-file.c @@ -1240,10 +1240,10 @@ int unpack_loose_header(git_zstream *stream, /* * We have a header longer than MAX_HEADER_LEN. We abort early * unless under we're running as e.g. "cat-file - * --allow-unknown-type". + * --allow-unknown-type". A -2 is "header too long" */ if (!header) - return -1; + return -2; /* * buffer[0..bufsiz] was not large enough. Copy the partial @@ -1264,7 +1264,7 @@ int unpack_loose_header(git_zstream *stream, stream->next_out = buffer; stream->avail_out = bufsiz; } while (status != Z_STREAM_END); - return -1; + return -2; } static void *unpack_loose_rest(git_zstream *stream, @@ -1433,9 +1433,14 @@ static int loose_object_info(struct repository *r, hdr_ret = unpack_loose_header(&stream, map, mapsize, hdr, sizeof(hdr), allow_unknown ? &hdrbuf : NULL); if (hdr_ret < 0) { - status = error(_("unable to unpack %s header"), - oid_to_hex(oid)); + if (hdr_ret == -2) + status = error(_("header for %s too long, exceeds %d bytes"), + oid_to_hex(oid), MAX_HEADER_LEN); + else + status = error(_("unable to unpack %s header"), + oid_to_hex(oid)); } + if (!status && parse_loose_header(hdrbuf.len ? hdrbuf.buf : hdr, oi) < 0) { status = error(_("unable to parse %s header"), oid_to_hex(oid)); } diff --git a/object-store.h b/object-store.h index 740edcac30..9accb614fc 100644 --- a/object-store.h +++ b/object-store.h @@ -481,13 +481,15 @@ int for_each_packed_object(each_packed_object_fn, void *, * unpack_loose_header() initializes the data stream needed to unpack * a loose object header. * - * Returns 0 on success. Returns negative values on error. + * Returns 0 on success. Returns negative values on error. If the + * header exceeds MAX_HEADER_LEN -2 will be returned. * * It will only parse up to MAX_HEADER_LEN bytes unless an optional * "hdrbuf" argument is non-NULL. This is intended for use with * OBJECT_INFO_ALLOW_UNKNOWN_TYPE to extract the bad type for (error) * reporting. The full header will be extracted to "hdrbuf" for use - * with parse_loose_header(). + * with parse_loose_header(), -2 will still be returned from this + * function to indicate that the header was too long. */ int unpack_loose_header(git_zstream *stream, unsigned char *map, unsigned long mapsize, void *buffer, diff --git a/t/t1006-cat-file.sh b/t/t1006-cat-file.sh index d3d3fd733a..f12b06150e 100755 --- a/t/t1006-cat-file.sh +++ b/t/t1006-cat-file.sh @@ -440,7 +440,7 @@ bogus_sha1=$(echo_without_newline "$bogus_content" | git hash-object -t $bogus_t test_expect_success 'die on broken object with large type under -t and -s without --allow-unknown-type' ' cat >err.expect <<-EOF && - error: unable to unpack $bogus_sha1 header + error: header for $bogus_sha1 too long, exceeds 32 bytes fatal: git cat-file: could not get object info EOF
-- 2.32.0.rc0.406.g73369325f8d