Fixed incorrect ngx_cpystrn() usage in ngx_http_*_process_header().

This resulted in a disclosure of previously freed memory if upstream
server returned specially crafted response, potentially exposing
sensitive information.

Reported by Matthew Daley.

4 files changed, 16 insertions, 10 deletions

diff --git a/src/http/modules/ngx_http_fastcgi_module.c b/src/http/modules/ngx_http_fastcgi_module.c
index bbdd64cdc..361b1c8db 100644
--- a/src/http/modules/ngx_http_fastcgi_module.c
+++ b/src/http/modules/ngx_http_fastcgi_module.c
@@ -1501,10 +1501,10 @@ ngx_http_fastcgi_process_header(ngx_http_request_t *r)
                     h->lowcase_key = h->key.data + h->key.len + 1
                                      + h->value.len + 1;
 
-                    ngx_cpystrn(h->key.data, r->header_name_start,
-                                h->key.len + 1);
-                    ngx_cpystrn(h->value.data, r->header_start,
-                                h->value.len + 1);
+                    ngx_memcpy(h->key.data, r->header_name_start, h->key.len);
+                    h->key.data[h->key.len] = '\0';
+                    ngx_memcpy(h->value.data, r->header_start, h->value.len);
+                    h->value.data[h->value.len] = '\0';
                 }
 
                 h->hash = r->header_hash;
diff --git a/src/http/modules/ngx_http_proxy_module.c b/src/http/modules/ngx_http_proxy_module.c
index 678c70e77..1a99e17df 100644
--- a/src/http/modules/ngx_http_proxy_module.c
+++ b/src/http/modules/ngx_http_proxy_module.c
@@ -1381,8 +1381,10 @@ ngx_http_proxy_process_header(ngx_http_request_t *r)
             h->value.data = h->key.data + h->key.len + 1;
             h->lowcase_key = h->key.data + h->key.len + 1 + h->value.len + 1;
 
-            ngx_cpystrn(h->key.data, r->header_name_start, h->key.len + 1);
-            ngx_cpystrn(h->value.data, r->header_start, h->value.len + 1);
+            ngx_memcpy(h->key.data, r->header_name_start, h->key.len);
+            h->key.data[h->key.len] = '\0';
+            ngx_memcpy(h->value.data, r->header_start, h->value.len);
+            h->value.data[h->value.len] = '\0';
 
             if (h->key.len == r->lowcase_index) {
                 ngx_memcpy(h->lowcase_key, r->lowcase_header, h->key.len);
diff --git a/src/http/modules/ngx_http_scgi_module.c b/src/http/modules/ngx_http_scgi_module.c
index bb9f6af51..a6c8caddf 100644
--- a/src/http/modules/ngx_http_scgi_module.c
+++ b/src/http/modules/ngx_http_scgi_module.c
@@ -941,8 +941,10 @@ ngx_http_scgi_process_header(ngx_http_request_t *r)
             h->value.data = h->key.data + h->key.len + 1;
             h->lowcase_key = h->key.data + h->key.len + 1 + h->value.len + 1;
 
-            ngx_cpystrn(h->key.data, r->header_name_start, h->key.len + 1);
-            ngx_cpystrn(h->value.data, r->header_start, h->value.len + 1);
+            ngx_memcpy(h->key.data, r->header_name_start, h->key.len);
+            h->key.data[h->key.len] = '\0';
+            ngx_memcpy(h->value.data, r->header_start, h->value.len);
+            h->value.data[h->value.len] = '\0';
 
             if (h->key.len == r->lowcase_index) {
                 ngx_memcpy(h->lowcase_key, r->lowcase_header, h->key.len);
diff --git a/src/http/modules/ngx_http_uwsgi_module.c b/src/http/modules/ngx_http_uwsgi_module.c
index 1470f7c7a..54172bab8 100644
--- a/src/http/modules/ngx_http_uwsgi_module.c
+++ b/src/http/modules/ngx_http_uwsgi_module.c
@@ -981,8 +981,10 @@ ngx_http_uwsgi_process_header(ngx_http_request_t *r)
             h->value.data = h->key.data + h->key.len + 1;
             h->lowcase_key = h->key.data + h->key.len + 1 + h->value.len + 1;
 
-            ngx_cpystrn(h->key.data, r->header_name_start, h->key.len + 1);
-            ngx_cpystrn(h->value.data, r->header_start, h->value.len + 1);
+            ngx_memcpy(h->key.data, r->header_name_start, h->key.len);
+            h->key.data[h->key.len] = '\0';
+            ngx_memcpy(h->value.data, r->header_start, h->value.len);
+            h->value.data[h->value.len] = '\0';
 
             if (h->key.len == r->lowcase_index) {
                 ngx_memcpy(h->lowcase_key, r->lowcase_header, h->key.len);