From: Junio C Hamano <gitster@pobox.com>
Date: Tue, 21 Mar 2017 22:03:25 +0000 (-0700)
Subject: Merge branch 'jk/http-walker-buffer-underflow-fix' into maint
X-Git-Tag: v2.12.2~22
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/36238fc4a59ae03e5574510dec3751745f98e940?hp=1a61be2a525e1a9285d922907c5b3a7ef8ecf17b

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
---

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));