Mercurial > hg > nginx

changeset 7829:2851e4c7de03

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Mail: fixed reading with fully filled buffer (ticket #2159). With SMTP pipelining, ngx_mail_read_command() can be called with s->buffer without any space available, to parse additional commands received to the buffer on previous calls. Previously, this resulted in recv() being called with zero length, resulting in zero being returned, which was interpreted as a connection close by the client, so nginx silently closed connection. Fix is to avoid calling c->recv() if there is no free space in the buffer, but continue parsing of the already received commands.
author Maxim Dounin <mdounin@mdounin.ru>
date Wed, 21 Apr 2021 23:24:59 +0300
parents c40f7a65c506
children f2ff291bbdac
files src/mail/ngx_mail_handler.c
diffstat 1 files changed, 14 insertions(+), 11 deletions(-) [+]
line wrap: on
line diff
--- a/src/mail/ngx_mail_handler.c
+++ b/src/mail/ngx_mail_handler.c
@@ -833,20 +833,23 @@ ngx_mail_read_command(ngx_mail_session_t
     ngx_str_t                  l;
     ngx_mail_core_srv_conf_t  *cscf;
 
-    n = c->recv(c, s->buffer->last, s->buffer->end - s->buffer->last);
+    if (s->buffer->last < s->buffer->end) {
+
+        n = c->recv(c, s->buffer->last, s->buffer->end - s->buffer->last);
 
-    if (n == NGX_ERROR || n == 0) {
-        ngx_mail_close_connection(c);
-        return NGX_ERROR;
-    }
+        if (n == NGX_ERROR || n == 0) {
+            ngx_mail_close_connection(c);
+            return NGX_ERROR;
+        }
 
-    if (n > 0) {
-        s->buffer->last += n;
-    }
+        if (n > 0) {
+            s->buffer->last += n;
+        }
 
-    if (n == NGX_AGAIN) {
-        if (s->buffer->pos == s->buffer->last) {
-            return NGX_AGAIN;
+        if (n == NGX_AGAIN) {
+            if (s->buffer->pos == s->buffer->last) {
+                return NGX_AGAIN;
+            }
         }
     }