From a11da6fc15ab7a3c2c6c7e8b451ae024fff0402d Mon Sep 17 00:00:00 2001
From: zaaarf <me@zaaarf.foo>
Date: Tue, 12 May 2026 13:55:21 +0200
Subject: [PATCH 1/5] ext/standard: Fix symlink trying to resolve dangling
 links

---
 ext/standard/link.c              | 10 +++++
 ext/standard/tests/gh21992t.phpt | 76 ++++++++++++++++++++++++++++++++
 2 files changed, 86 insertions(+)
 create mode 100644 ext/standard/tests/gh21992t.phpt

diff --git a/ext/standard/link.c b/ext/standard/link.c
index df2831b87846..8e94f016bea0 100644
--- a/ext/standard/link.c
+++ b/ext/standard/link.c
@@ -131,11 +131,21 @@ PHP_FUNCTION(symlink)
 	char dirname[MAXPATHLEN];
 	size_t len;
 
+	zend_stat_t v_lstat = {0};
+	zend_stat_t v_stat = {0};
+
 	ZEND_PARSE_PARAMETERS_START(2, 2)
 		Z_PARAM_PATH(topath, topath_len)
 		Z_PARAM_PATH(frompath, frompath_len)
 	ZEND_PARSE_PARAMETERS_END();
 
+	// dangling link should be treated as existing file
+	ret = VCWD_LSTAT(frompath, &v_lstat);
+	if (!ret && S_ISLNK(v_lstat.st_mode) && VCWD_STAT(frompath, &v_stat)) {
+		php_error_docref(NULL, E_WARNING, "File exists in %s", frompath);
+		RETURN_FALSE;
+	}
+
 	if (!expand_filepath(frompath, source_p)) {
 		php_error_docref(NULL, E_WARNING, "No such file or directory");
 		RETURN_FALSE;
diff --git a/ext/standard/tests/gh21992t.phpt b/ext/standard/tests/gh21992t.phpt
new file mode 100644
index 000000000000..1fa08336b531
--- /dev/null
+++ b/ext/standard/tests/gh21992t.phpt
@@ -0,0 +1,76 @@
+--TEST--
+GH-21992: symlink() must not resolve the final dangling link component
+--SKIPIF--
+<?php
+if (PHP_OS_FAMILY === 'Windows') {
+    die('not for Windows');
+}
+?>
+--FILE--
+<?php
+$dir = __DIR__ . '/gh21992';
+$targetDir = $dir . '/target_dir';
+
+// dangling link to nonexisting $ghost
+$deadLink = $dir . '/dead_link.txt';
+$ghost = $targetDir . '/ghost.txt';
+$newTarget = $dir . '/nothing';
+
+// real link to $realFile
+$realLink = $dir . '/real_link.txt';
+$realFile = $targetDir . '/real.txt';
+$realTarget = $dir . '/something';
+
+mkdir($dir);
+mkdir($targetDir);
+touch($realFile); // ensure $realFile exists
+
+// verify the real file works fine
+var_dump(symlink($realFile, $realLink));
+var_dump(readlink($realLink));
+var_dump(symlink($realTarget, $realLink));
+var_dump(is_link($realLink));
+var_dump(readlink($realLink));
+var_dump(is_link($realFile));
+
+// verify the ghost file works as intended
+var_dump(symlink($ghost, $deadLink));
+var_dump(readlink($deadLink));
+var_dump(symlink($newTarget, $deadLink));
+var_dump(is_link($deadLink));
+var_dump(readlink($deadLink));
+var_dump(is_link($ghost));
+?>
+--CLEAN--
+<?php
+$dir = __DIR__ . '/gh21992';
+$targetDir = $dir . '/target_dir';
+$deadLink = $dir . '/dead_link.txt';
+$ghost = $targetDir . '/ghost.txt';
+$realLink = $dir . '/real_link.txt';
+$realFile = $targetDir . '/real.txt';
+
+@unlink($ghost);
+@unlink($deadLink);
+@unlink($realLink);
+@unlink($realFile);
+@rmdir($targetDir);
+@rmdir($dir);
+?>
+--EXPECTF--
+bool(true)
+string(%d) "%s/gh21992/target_dir/real.txt"
+
+Warning: symlink(): File exists in %s on line %d
+bool(false)
+bool(true)
+string(%d) "%s/gh21992/target_dir/real.txt"
+bool(false)
+bool(true)
+string(%d) "%s/gh21992/target_dir/ghost.txt"
+
+Warning: symlink(): File exists in %s on line %d
+bool(false)
+bool(true)
+string(%d) "%s/gh21992/target_dir/ghost.txt"
+bool(false)

From 7bd502d93b4a05c41f7819d6c71eed9ce94dbf65 Mon Sep 17 00:00:00 2001
From: zaaarf <me@zaaarf.foo>
Date: Wed, 13 May 2026 02:21:24 +0200
Subject: [PATCH 2/5] try to fix test

---
 ext/standard/tests/gh21992t.phpt | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/ext/standard/tests/gh21992t.phpt b/ext/standard/tests/gh21992t.phpt
index 1fa08336b531..6a883decea72 100644
--- a/ext/standard/tests/gh21992t.phpt
+++ b/ext/standard/tests/gh21992t.phpt
@@ -3,7 +3,8 @@ GH-21992: symlink() must not resolve the final dangling link component
 --SKIPIF--
 <?php
 if (PHP_OS_FAMILY === 'Windows') {
-    die('not for Windows');
+    require_once __DIR__ . '/windows_links/common.inc';
+    skipIfSeCreateSymbolicLinkPrivilegeIsDisabled(__FILE__);
 }
 ?>
 --FILE--

From 5b7b6d84132813b4a4cb01610fad2bec626ef8fb Mon Sep 17 00:00:00 2001
From: zaaarf <me@zaaarf.foo>
Date: Wed, 13 May 2026 02:32:25 +0200
Subject: [PATCH 3/5] actually fix windows test

---
 ext/standard/tests/gh21992t.phpt | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/ext/standard/tests/gh21992t.phpt b/ext/standard/tests/gh21992t.phpt
index 6a883decea72..9c65bc16f8b8 100644
--- a/ext/standard/tests/gh21992t.phpt
+++ b/ext/standard/tests/gh21992t.phpt
@@ -60,18 +60,18 @@ $realFile = $targetDir . '/real.txt';
 ?>
 --EXPECTF--
 bool(true)
-string(%d) "%s/gh21992/target_dir/real.txt"
+string(%d) "%s%egh21992%etarget_dir%ereal.txt"
 
 Warning: symlink(): File exists in %s on line %d
 bool(false)
 bool(true)
-string(%d) "%s/gh21992/target_dir/real.txt"
+string(%d) "%s%egh21992%etarget_dir%ereal.txt"
 bool(false)
 bool(true)
-string(%d) "%s/gh21992/target_dir/ghost.txt"
+string(%d) "%s%egh21992%etarget_dir%eghost.txt"
 
 Warning: symlink(): File exists in %s on line %d
 bool(false)
 bool(true)
-string(%d) "%s/gh21992/target_dir/ghost.txt"
+string(%d) "%s%egh21992%etarget_dir%eghost.txt"
 bool(false)

From cd6ddb8f396a1078451102a082914177b26b3c8c Mon Sep 17 00:00:00 2001
From: zaaarf <me@zaaarf.foo>
Date: Wed, 13 May 2026 03:04:59 +0200
Subject: [PATCH 4/5] better warning message

---
 ext/standard/link.c              | 2 +-
 ext/standard/tests/gh21992t.phpt | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/ext/standard/link.c b/ext/standard/link.c
index 8e94f016bea0..948cf618c02e 100644
--- a/ext/standard/link.c
+++ b/ext/standard/link.c
@@ -142,7 +142,7 @@ PHP_FUNCTION(symlink)
 	// dangling link should be treated as existing file
 	ret = VCWD_LSTAT(frompath, &v_lstat);
 	if (!ret && S_ISLNK(v_lstat.st_mode) && VCWD_STAT(frompath, &v_stat)) {
-		php_error_docref(NULL, E_WARNING, "File exists in %s", frompath);
+		php_error_docref(NULL, E_WARNING, "Dangling symlink at %s", frompath);
 		RETURN_FALSE;
 	}
 
diff --git a/ext/standard/tests/gh21992t.phpt b/ext/standard/tests/gh21992t.phpt
index 9c65bc16f8b8..15e6fedab46d 100644
--- a/ext/standard/tests/gh21992t.phpt
+++ b/ext/standard/tests/gh21992t.phpt
@@ -70,7 +70,7 @@ bool(false)
 bool(true)
 string(%d) "%s%egh21992%etarget_dir%eghost.txt"
 
-Warning: symlink(): File exists in %s on line %d
+Warning: symlink(): Dangling symlink at %s on line %d
 bool(false)
 bool(true)
 string(%d) "%s%egh21992%etarget_dir%eghost.txt"

From b8b1b39c80c491df8db4fbf28ca4b274f84efb7f Mon Sep 17 00:00:00 2001
From: zaaarf <me@zaaarf.foo>
Date: Wed, 13 May 2026 03:06:15 +0200
Subject: [PATCH 5/5] fix test for windows

---
 ext/standard/tests/gh21992t.phpt | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/ext/standard/tests/gh21992t.phpt b/ext/standard/tests/gh21992t.phpt
index 15e6fedab46d..60af0d2bcb1d 100644
--- a/ext/standard/tests/gh21992t.phpt
+++ b/ext/standard/tests/gh21992t.phpt
@@ -3,8 +3,7 @@ GH-21992: symlink() must not resolve the final dangling link component
 --SKIPIF--
 <?php
 if (PHP_OS_FAMILY === 'Windows') {
-    require_once __DIR__ . '/windows_links/common.inc';
-    skipIfSeCreateSymbolicLinkPrivilegeIsDisabled(__FILE__);
+    die('skip (not for Windows)');
 }
 ?>
 --FILE--