sha1_file: avoid overrunning alternate object base string

PATCH New René Scharfe 1 participant 1 message Jun 15, 2016

Share & tools

René Scharfe

author

2016-06-15 23:01 UTC #0 lore raw

PATCH 1/1 sha1_file: avoid overrunning alternate object base string

While checking if a new alternate object database is a duplicate make sure that old and new base paths have the same length before comparing them with memcmp. This avoids overrunning the buffer of the existing entry if the new one is longer and it stops rejecting foobar/ after foo/ was already added.

Signed-off-by Rene Scharfe <[email protected]>

---
 sha1_file.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

sha1_file.c +2 -1

index 8adab14..b7ad6c1 100644
@@ -315,7 +315,8 @@ static int link_alt_odb_entry(const char *entry, const char *relative_base, int
 	 * thing twice, or object directory itself.
 	 */
 	for (alt = alt_odb_list; alt; alt = alt->next) {
-		if (!memcmp(ent->base, alt->base, pfxlen)) {
+		if (pfxlen == alt->name - alt->base - 1 &&
+		    !memcmp(ent->base, alt->base, pfxlen)) {
 			free(ent);
 			return -1;
 		}

Signature · 1 line

2.0.0