From 983fbff8711a8c625e494a981891a90d47847e14 Mon Sep 17 00:00:00 2001
From: florian <florian@freepascal.org>
Date: Sun, 2 Jan 2022 21:46:14 +0100
Subject: [PATCH]   * proper range checking for TryStrToDWord, should resolve
 all issues in #39406

---
 rtl/objpas/sysutils/sysstr.inc | 10 +++++++---
 tests/webtbs/tw39406.pp        | 14 ++++++++++++++
 2 files changed, 21 insertions(+), 3 deletions(-)
 create mode 100644 tests/webtbs/tw39406.pp

diff --git a/rtl/objpas/sysutils/sysstr.inc b/rtl/objpas/sysutils/sysstr.inc
index 7ed0396587..b4ee1814db 100644
--- a/rtl/objpas/sysutils/sysstr.inc
+++ b/rtl/objpas/sysutils/sysstr.inc
@@ -1007,10 +1007,14 @@ begin
 end;
 
 function TryStrToDWord(const s: string; Out D: DWord): boolean;
-var Error : word;
+var 
+  Error : word;
+  lq : QWord;
 begin
-  Val(s, D, Error);
-  TryStrToDWord:=Error=0
+  Val(s, lq, Error);
+  TryStrToDWord:=(Error=0) and (lq<=High(DWord));
+  if TryStrToDWord then
+    D:=lq;
 end;
 
 function StrToUInt(const s: string): Cardinal;
diff --git a/tests/webtbs/tw39406.pp b/tests/webtbs/tw39406.pp
new file mode 100644
index 0000000000..7d6e67c6eb
--- /dev/null
+++ b/tests/webtbs/tw39406.pp
@@ -0,0 +1,14 @@
+{$mode objfpc}
+program fpbug;
+
+uses
+  SysUtils;
+
+var
+  Value:   Cardinal;
+  Success: Boolean;
+begin
+  Success := TryStrToDword('7795000000', Value);
+  if Success then
+    halt(1);
+end.