[PATCH] sha1_file: release fallback base's memory in unpack_entry()

["René Scharfe" <l.s.r@web.de>]

If a pack entry that's used as a delta base is corrupt, unpack_entry()
marks it as unusable and then searches the object again in the hope that
it can be found in another pack or in a loose file.  The memory for this
external base object is never released.  Free it after use.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
---
 sha1_file.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sha1_file.c b/sha1_file.c
index ec957db5e1..8ce80d4481 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -2532,6 +2532,7 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset,
 	while (delta_stack_nr) {
 		void *delta_data;
 		void *base = data;
+		void *external_base = NULL;
 		unsigned long delta_size, base_size = size;
 		int i;
 
@@ -2558,6 +2559,7 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset,
 				      p->pack_name);
 				mark_bad_packed_object(p, base_sha1);
 				base = read_object(base_sha1, &type, &base_size);
+				external_base = base;
 			}
 		}
 
@@ -2576,6 +2578,7 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset,
 			      "at offset %"PRIuMAX" from %s",
 			      (uintmax_t)curpos, p->pack_name);
 			data = NULL;
+			free(external_base);
 			continue;
 		}
 
@@ -2595,6 +2598,7 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset,
 			error("failed to apply delta");
 
 		free(delta_data);
+		free(external_base);
 	}
 
 	*final_type = type;
-- 
2.12.0