[PATCH] sha1_file: release delta_stack on error in unpack_entry()

["René Scharfe" <l.s.r@web.de>]

When unpack_entry() encounters a broken packed object, it returns early.
It adjusts the reference count of the pack window, but leaks the buffer
for a big delta stack in case the small automatic one was not enough.
Jump to the cleanup code at end instead, which takes care of that.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
---
 sha1_file.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/sha1_file.c b/sha1_file.c
index b60ae15f70..b7bb38b445 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -2542,8 +2542,8 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset,
 				error("bad packed object CRC for %s",
 				      sha1_to_hex(sha1));
 				mark_bad_packed_object(p, sha1);
-				unuse_pack(&w_curs);
-				return NULL;
+				data = NULL;
+				goto out;
 			}
 		}
 
@@ -2681,6 +2681,7 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset,
 	if (final_size)
 		*final_size = size;
 
+out:
 	unuse_pack(&w_curs);
 
 	if (delta_stack != small_delta_stack)
-- 
2.14.0