From: Ruslan Ermilov <ru@nginx.com>
Date: Mon, 5 Jul 2021 10:09:23 +0000 (+0300)
Subject: Use only preallocated memory in ngx_readv_chain() (ticket #1408).
X-Git-Tag: release-1.21.1~2
X-Git-Url: http://www.kaiwu.me/postgresql/commit/?a=commitdiff_plain;h=b20768e61cd3569160a57e2f0e2e6d0def87792e;p=nginx.git

Use only preallocated memory in ngx_readv_chain() (ticket #1408).

In d1bde5c3c5d2, the number of preallocated iovec's for ngx_readv_chain()
was increased.  Still, in some setups, the function might allocate memory
for iovec's from a connection pool, which is only freed when closing the
connection.

The ngx_readv_chain() function was modified to use only preallocated
memory, similarly to the ngx_writev_chain() change in 8e903522c17a.
---

diff --git a/src/os/unix/ngx_readv_chain.c b/src/os/unix/ngx_readv_chain.c
index a3577ce19..b1ae4b51d 100644
--- a/src/os/unix/ngx_readv_chain.c
+++ b/src/os/unix/ngx_readv_chain.c
@@ -96,7 +96,7 @@ ngx_readv_chain(ngx_connection_t *c, ngx_chain_t *chain, off_t limit)
             iov->iov_len += n;
 
         } else {
-            if (vec.nelts >= IOV_MAX) {
+            if (vec.nelts == vec.nalloc) {
                 break;
             }