Merge branch 'jk/http-walker-buffer-underflow-fix' into maint

"Dumb http" transport used to misparse a nonsense http-alternates
response, which has been fixed.

* jk/http-walker-buffer-underflow-fix:
  http-walker: fix buffer underflow processing remote alternates

1 files changed, 7 insertions, 4 deletions

diff --git a/http-walker.c b/http-walker.c
index b34b6ace7c..507c200f00 100644
--- a/http-walker.c
+++ b/http-walker.c
@@ -296,13 +296,16 @@ static void process_alternates_response(void *callback_data)
 					okay = 1;
 				}
 			}
-			/* skip "objects\n" at end */
 			if (okay) {
 				struct strbuf target = STRBUF_INIT;
 				strbuf_add(&target, base, serverlen);
-				strbuf_add(&target, data + i, posn - i - 7);
-
-				if (is_alternate_allowed(target.buf)) {
+				strbuf_add(&target, data + i, posn - i);
+				if (!strbuf_strip_suffix(&target, "objects")) {
+					warning("ignoring alternate that does"
+						" not end in 'objects': %s",
+						target.buf);
+					strbuf_release(&target);
+				} else if (is_alternate_allowed(target.buf)) {
 					warning("adding alternate object store: %s",
 						target.buf);
 					newalt = xmalloc(sizeof(*newalt));