Re: [PATCH] archive-tar: fix sanity check in config parsing

Jeff King wrote:

On Sun, Jan 13, 2013 at 06:42:01PM +0100, René Scharfe wrote:

quoted

When parsing these config variable names, we currently check that
the second dot is found nine characters into the name, disallowing
filter names with a length of five characters.  Additionally,
git archive crashes when the second dot is omitted:

$ ./git -c tar.foo=bar archive HEAD >/dev/null
fatal: Data too large to fit into virtual memory space.

Instead we should check if the second dot exists at all, or if
we only found the first one.

Eek. Thanks for finding it. Your fix is obviously correct.

quoted

--- a/archive-tar.c
+++ b/archive-tar.c

@@ -335,7 +335,7 @@ static int tar_filter_config(const char *var,
 const char *value, void *data) if (prefixcmp(var, "tar."))
 return 0;
 dot = strrchr(var, '.');
- if (dot == var + 9)
+ if (dot == var + 3)
 return 0;

For the curious, the original version of the patch[1] read:

+       if (prefixcmp(var, "tarfilter."))
+               return 0;
+       dot = strrchr(var, '.');
+       if (dot == var + 9)
+               return 0;

and when I shortened the config section to "tar" in a re-roll of the
series, I missed the corresponding change to the offset.

Wouldn't it then be better ti use strlen("tar") rather than a 3? Or at least a comment?

Bye, Jojo