On Thu, Oct 15, 2009 at 09:39, Junio C Hamano <gitster@xxxxxxxxx> wrote:
> Nicolas Pitre <nico@xxxxxxxxxxx> writes:
>
>> I confirm this test without the fix reproduces the infinite loop (and
>> does stall the test suite).
>
> Thanks, both of you.
I seem to have problems with this change (on Cygwin). Sometimes
accessing an object in a pack fails in unpack_compressed_entry.
When it happens, both avail_in and avail_out of the stream are 0,
and the reported status is Z_BUF_ERROR.
Output with the second attached patch:
error: *** inflate error: 0x862380 size=1256, avail_in=0 (was 697),
avail_out=0 (was 1256)
error: *** unpack_compressed_entry failed
error: failed to read object 3296766eb5531ef051ae392114de5d75556f5613
at offset 2620741 from
.git/objects/pack/pack-996206790aaefbf4d34c86b3ff546bb924546b7c.pack
fatal: object 3296766eb5531ef051ae392114de5d75556f5613 is corrupted
I cannot reproduce the problem on a normal system (a 64bit, reasonably modern
Linux in my case). An attempt to use an upgraded zlib on this cygwin system was
not successful, there was an updated library, but a clean recompile didn't
change anything.
I worked the case around by allocating a bit more than uncompressed data need.
In case someone else also sees the problem, below is how. The size of the
overallocation is arbitrary.
diff --git a/sha1_file.c b/sha1_file.c
index 4cc8939..66c2519 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1585,11 +1585,11 @@ static void *unpack_compressed_entry(struct
packed_git *p,
z_stream stream;
unsigned char *buffer, *in;
- buffer = xmalloc(size + 1);
- buffer[size] = 0;
+ buffer = xmalloc(size + 8);
+ memset(buffer + size, 0, 8);
memset(&stream, 0, sizeof(stream));
stream.next_out = buffer;
- stream.avail_out = size;
+ stream.avail_out = size + 8;
git_inflate_init(&stream);
do {
--
1.6.5.59.g000dd
The problematic repo is a little big to post (it's my cygwin-git repo),
I'll have to find hosting for it first.
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