From 5815730864a2010872840bae24797983e892eb90 Mon Sep 17 00:00:00 2001

From: Daniel Stenberg <daniel@haxx.se>

Date: Sat, 24 Mar 2018 23:47:41 +0100

Subject: [PATCH] http: restore buffer pointer when bad response-line is parsed

... leaving the k->str could lead to buffer over-reads later on.

CVE: CVE-2018-1000301

Assisted-by: Max Dymond

Detected by OSS-Fuzz.

Bug: https://curl.haxx.se/docs/adv_2018-b138.html

Bug: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=7105

Upstream-commit: 8c7b3737d29ed5c0575bf592063de8a51450812d

Signed-off-by: Kamil Dudka <kdudka@redhat.com>

---

 lib/http.c | 6 +++++-

 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/http.c b/lib/http.c

index 841f6cc..dc10f5f 100644

--- a/lib/http.c

+++ b/lib/http.c

@@ -2791,6 +2791,8 @@ CURLcode Curl_http_readwrite_headers(struct SessionHandle *data,

 {

   CURLcode result;

   struct SingleRequest *k = &data->req;

+  ssize_t onread = *nread;

+  char *ostr = k->str;

   /* header line within buffer loop */

   do {

@@ -2855,7 +2857,9 @@ CURLcode Curl_http_readwrite_headers(struct SessionHandle *data,

         else {

           /* this was all we read so it's all a bad header */

           k->badheader = HEADER_ALLBAD;

-          *nread = (ssize_t)rest_length;

+          *nread = onread;

+          k->str = ostr;

+          return CURLE_OK;

         }

         break;

       }

-- 

2.14.3