[PATCH] fix segfault in fsck-cache

[PATCH] fix segfault in fsck-cache

Here is how to trigger it:

   echo blob 100 > .git/objects/00/ae4e8d3208e09f2cf7a38202a126f728cadb49

Then run fsck-cache. It will try to unpack after the header to calculate
the hash, inflate returns total_out == 0 and memcpy() dies.

The patch below seems to work with ZLIB 1.1 and 1.2.

Signed-off-by: Andreas Gal <gal@uci.edu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>