[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>

diff --git a/sha1_file.c b/sha1_file.c
index 97a515a073fec5870dfaaa279868ce9330853d3d..28ad1598e54200ca8ee1261ed7beb4e31e20b2f1 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -155,6 +155,8 @@ void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned l
 
        inflateInit(&stream);
        ret = inflate(&stream, 0);
+       if (ret < Z_OK)
+               return NULL;
        if (sscanf(buffer, "%10s %lu", type, size) != 2)
                return NULL;