From: Aaron Ballman <aaron@aaronballman.com>
Date: Wed, 1 May 2013 02:53:14 +0000 (+0000)
Subject: Fixes a buffer overrun where the allocated buffer wasn't large enough to accommodate... 
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=af35d86bbd9a970d5bb55595a569ea60962bf23d;p=oota-llvm.git

Fixes a buffer overrun where the allocated buffer wasn't large enough to accommodate the closing quote escape rules in some instances.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180836 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Support/Windows/Program.inc b/lib/Support/Windows/Program.inc
index 4a4ed2f84b1..619ae5d8f71 100644
--- a/lib/Support/Windows/Program.inc
+++ b/lib/Support/Windows/Program.inc
@@ -155,7 +155,8 @@ static char *EscapePrecedingEscapes(char *Dst, const char *Start,
 /// CreateProcess and returns length of quoted arg with escaped quotes
 static unsigned int ArgLenWithQuotes(const char *Str) {
   const char *Start = Str;
-  unsigned int len = ArgNeedsQuotes(Str) ? 2 : 0;
+  bool Quoted = ArgNeedsQuotes(Str);
+  unsigned int len = Quoted ? 2 : 0;
 
   while (*Str != '\0') {
     if (*Str == '\"') {
@@ -171,6 +172,12 @@ static unsigned int ArgLenWithQuotes(const char *Str) {
     ++Str;
   }
 
+  if (Quoted) {
+    // Make sure the closing quote doesn't get escaped by a trailing backslash.
+    unsigned PrecedingEscapes = CountPrecedingBackslashes(Start, Str);
+    len += PrecedingEscapes + 1;
+  }
+
   return len;
 }