httpd: fix proxy headers passing - full_write() instead of write()

function                                             old     new   delta
handle_incoming_and_exit                            2763    2752     -11

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 16 insertions, 11 deletions

diff --git a/networking/httpd.c b/networking/httpd.c
index f713f6929..c486197b8 100644
--- a/networking/httpd.c
+++ b/networking/httpd.c
@@ -2271,15 +2271,20 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                                 bb_error_msg("header: '%s'", iobuf);
 
 #if ENABLE_FEATURE_HTTPD_PROXY
-                        /* We need 2 more bytes for yet another "\r\n" -
-                         * see near fdprintf(proxy_fd...) further below */
-                        if (proxy_entry && (header_ptr - header_buf) < IOBUF_SIZE - 4) {
-                                int len = strnlen(iobuf, IOBUF_SIZE - (header_ptr - header_buf) - 4);
-                                memcpy(header_ptr, iobuf, len);
-                                header_ptr += len;
-                                header_ptr[0] = '\r';
-                                header_ptr[1] = '\n';
-                                header_ptr += 2;
+                        if (proxy_entry) {
+                                /* Why 4, not 2?
+                                 * We need 2 more bytes for yet another "\r\n" -
+                                 * see near fdprintf(proxy_fd...) further below.
+                                 */
+                                int maxlen = (IOBUF_SIZE-4) - (int)(header_ptr - header_buf);
+                                if (maxlen > 0) {
+                                        int len = strnlen(iobuf, maxlen);
+                                        memcpy(header_ptr, iobuf, len);
+                                        header_ptr += len;
+                                        header_ptr[0] = '\r';
+                                        header_ptr[1] = '\n';
+                                        header_ptr += 2;
+                                }
                         }
 #endif
 
@@ -2401,7 +2406,7 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
         }
 
 #if ENABLE_FEATURE_HTTPD_PROXY
-        if (proxy_entry != NULL) {
+        if (proxy_entry) {
                 int proxy_fd;
                 len_and_sockaddr *lsa;
 
@@ -2423,7 +2428,7 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                 header_ptr[0] = '\r';
                 header_ptr[1] = '\n';
                 header_ptr += 2;
-                write(proxy_fd, header_buf, header_ptr - header_buf);
+                full_write(proxy_fd, header_buf, header_ptr - header_buf);
                 free(header_buf); /* on the order of 8k, free it */
                 cgi_io_loop_and_exit(proxy_fd, proxy_fd, length);
         }