From cddcc10becb013ae498ea9c2836792f407b61678 Mon Sep 17 00:00:00 2001
From: Julien Lepiller <julien@lepiller.eu>
Date: Tue, 7 Feb 2023 22:55:59 +0100
Subject: [PATCH] Fix file corruption when using copy_file_range.
This patch is adapted from https://github.com/php/php-src/pull/10440.
---
main/streams/streams.c | 21 +++++++++++++++++----
1 file changed, 17 insertions(+), 4 deletions(-)
diff --git a/main/streams/streams.c b/main/streams/streams.c
index 20029fc7..68dc76c5 100644
--- a/main/streams/streams.c
+++ b/main/streams/streams.c
@@ -1634,8 +1634,21 @@ PHPAPI zend_result _php_stream_copy_to_stream_ex(php_stream *src, php_stream *de
char *p;
do {
- size_t chunk_size = (maxlen == 0 || maxlen > PHP_STREAM_MMAP_MAX) ? PHP_STREAM_MMAP_MAX : maxlen;
- size_t mapped;
+ /* We must not modify maxlen here, because otherwise the file copy fallback below can fail */
+ size_t chunk_size, must_read, mapped;
+ if (maxlen == 0) {
+ /* Unlimited read */
+ must_read = chunk_size = PHP_STREAM_MMAP_MAX;
+ } else {
+ must_read = maxlen - haveread;
+ if (must_read >= PHP_STREAM_MMAP_MAX) {
+ chunk_size = PHP_STREAM_MMAP_MAX;
+ } else {
+ /* In case the length we still have to read from the file could be smaller than the file size,
+ * chunk_size must not get bigger the size we're trying to read. */
+ chunk_size = must_read;
+ }
+ }
p = php_stream_mmap_range(src, php_stream_tell(src), chunk_size, PHP_STREAM_MAP_MODE_SHARED_READONLY, &mapped);
@@ -1667,8 +1680,8 @@ PHPAPI zend_result _php_stream_copy_to_stream_ex(php_stream *src, php_stream *de
return SUCCESS;
}
if (maxlen != 0) {
- maxlen -= mapped;
- if (maxlen == 0) {
+ must_read -= mapped;
+ if (must_read == 0) {
return SUCCESS;
}
}
--
2.38.1