[PATCH 3/9] make unpack_object_header() non fatal
- From
Nicolas Pitre <nico@cam.org>
- Date
- Oct 29, 2008, 23:02 UTC
- Message-ID
- <1225321372-6570-4-git-send-email-nico@cam.org>
- In-Reply-To
- <1225321372-6570-3-git-send-email-nico@cam.org>
It is possible to have pack corruption in the object header. Currently unpack_object_header() simply die() on them instead of letting the caller deal with that gracefully.
So let's have unpack_object_header() return an error instead, and find a better name for unpack_object_header_gently() in that context. All callers of unpack_object_header() are ready for it.
Signed-off-by: Nicolas Pitre <nico@cam.org> --- builtin-pack-objects.c | 2 +- cache.h | 2 +- sha1_file.c | 20 +++++++++++--------- 3 files changed, 13 insertions(+), 11 deletions(-)
diff --git a/builtin-pack-objects.c b/builtin-pack-objects.c index d4c721b..9e249c9 100644 --- a/builtin-pack-objects.c +++ b/builtin-pack-objects.c @@ -1002,7 +1002,7 @@ static void check_object(struct object_entry *entry) * We want in_pack_type even if we do not reuse delta * since non-delta representations could still be reused. */ - used = unpack_object_header_gently(buf, avail, + used = unpack_object_header_buffer(buf, avail, &entry->in_pack_type, &entry->size); diff --git a/cache.h b/cache.h index a3c77f0..1a9edf3 100644 --- a/cache.h +++ b/cache.h @@ -751,7 +751,7 @@ extern const unsigned char *nth_packed_object_sha1(struct packed_git *, uint32_t extern off_t nth_packed_object_offset(const struct packed_git *, uint32_t); extern off_t find_pack_entry_one(const unsigned char *, struct packed_git *); extern void *unpack_entry(struct packed_git *, off_t, enum object_type *, unsigned long *); -extern unsigned long unpack_object_header_gently(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep); +extern unsigned long unpack_object_header_buffer(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep); extern unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t); extern const char *packed_object_info_detail(struct packed_git *, off_t, unsigned long *, unsigned long *, unsigned int *, unsigned char *); extern int matches_pack_name(struct packed_git *p, const char *name); diff --git a/sha1_file.c b/sha1_file.c index e57949b..7698177 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -1110,7 +1110,8 @@ static int legacy_loose_object(unsigned char *map) return 0; } -unsigned long unpack_object_header_gently(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep) +unsigned long unpack_object_header_buffer(const unsigned char *buf, + unsigned long len, enum object_type *type, unsigned long *sizep) { unsigned shift; unsigned char c; @@ -1122,10 +1123,10 @@ unsigned long unpack_object_header_gently(const unsigned char *buf, unsigned lon size = c & 15; shift = 4; while (c & 0x80) { - if (len <= used) - return 0; - if (sizeof(long) * 8 <= shift) + if (len <= used || sizeof(long) * 8 <= shift) { + error("bad object header"); return 0; + } c = buf[used++]; size += (c & 0x7f) << shift; shift += 7; @@ -1164,7 +1165,7 @@ static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned lon * really worth it and we don't write it any longer. But we * can still read it. */ - used = unpack_object_header_gently(map, mapsize, &type, &size); + used = unpack_object_header_buffer(map, mapsize, &type, &size); if (!used || !valid_loose_object_type[type]) return -1; map += used; @@ -1411,10 +1412,11 @@ static int unpack_object_header(struct packed_git *p, * insane, so we know won't exceed what we have been given. */ base = use_pack(p, w_curs, *curpos, &left); - used = unpack_object_header_gently(base, left, &type, sizep); - if (!used) - die("object offset outside of pack file"); - *curpos += used; + used = unpack_object_header_buffer(base, left, &type, sizep); + if (!used) { + type = OBJ_BAD; + } else + *curpos += used; return type; }
-- 1.6.0.3.757.g01be.dirty