From 8c7b3737d29ed5c0575bf592063de8a51450812d 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 --- lib/http.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/lib/http.c b/lib/http.c index 1a313b4fb..e080ae513 100644 --- a/lib/http.c +++ b/lib/http.c @@ -3012,10 +3012,12 @@ CURLcode Curl_http_readwrite_headers(struct Curl_easy *data, ssize_t *nread, bool *stop_reading) { CURLcode result; struct SingleRequest *k = &data->req; + ssize_t onread = *nread; + char *ostr = k->str; /* header line within buffer loop */ do { size_t rest_length; size_t full_length; @@ -3076,11 +3078,13 @@ CURLcode Curl_http_readwrite_headers(struct Curl_easy *data, /* since there's more, this is a partial bad header */ k->badheader = HEADER_PARTHEADER; 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; } } -- 2.17.0