Merge branch 'PHP-7.4' into PHP-8.0

* PHP-7.4:
  fileinfo: Fixed bug #78987 High memory usage during encoding detection

Author: weltling

ext/fileinfo/libmagic/encoding.c

@@ -70,7 +70,7 @@ file_encoding(struct magic_set *ms, const struct buffer *b, unicodechar **ubuf,
     size_t *ulen, const char **code, const char **code_mime, const char **type)
 {
 	const unsigned char *buf = CAST(const unsigned char *, b->fbuf);
-	size_t nbytes = b->flen;
+	size_t nbytes = b->flen > 64*1024 ? 64*1024 : b->flen;
 	size_t mlen;
 	int rv = 1, ucs_type;
 	unsigned char *nbuf = NULL;

ext/fileinfo/tests/bug78987.phpt

@@ -0,0 +1,40 @@
+--TEST--
+Bug #78987 High memory usage during encoding detection
+--SKIPIF--
+<?php require_once(__DIR__ . '/skipif.inc'); ?>
+--INI--
+memory_limit=512M
+--FILE--
+<?php
+$finfo = new finfo(FILEINFO_MIME_TYPE);
+$minSize = 128 * 1024;
+$maxSize = 16 * 1024 * 1024;
+
+$map = array(
+	131072 => 2097152,
+	262144 => 2097152,
+	524288 => 2097152,
+	1048576 => 4194304,
+	2097152 => 6295552,
+	4194304 => 10493952,
+	8388608 => 16785408,
+	16777216 => 29368320,
+);
+for($size = $minSize; $size <= $maxSize; $size *= 2) {
+	$content = str_repeat('0', $size);
+
+	$finfo->buffer($content);
+
+	$m = memory_get_peak_usage(true);
+	printf("%-8d => %s\n", $size, $m <= $map[$size] ? "ok" : "$m");
+}
+?>
+--EXPECT--
+131072   => ok
+262144   => ok
+524288   => ok
+1048576  => ok
+2097152  => ok
+4194304  => ok
+8388608  => ok
+16777216 => ok

ext/fileinfo/tests/finfo_file_basic.phpt

@@ -24,5 +24,5 @@ try {
 *** Testing finfo_file() : basic functionality ***
 string(28) "text/x-php; charset=us-ascii"
 string(22) "PHP script, ASCII text"
-string(25) "text/plain; charset=utf-8"
+string(28) "text/plain; charset=us-ascii"
 finfo_file(): Argument #1 ($finfo) must not contain any null bytes