From 8ecdbf2d5f40bb298702c6637dc98a0b30c2d7a1 Mon Sep 17 00:00:00 2001
From: Reid Spencer <rspencer@reidspencer.com>
Date: Tue, 22 May 2007 19:07:45 +0000
Subject: [PATCH] Don't allow the UnEscape code to read or write beyond the end
of yytext. Make sure we convert \\ into \.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37293 91177308-0d34-0410-b5e6-96231b3b80d8
---
lib/AsmParser/Lexer.l | 31 ++++++++++++++++++++-----------
1 file changed, 20 insertions(+), 11 deletions(-)
diff --git a/lib/AsmParser/Lexer.l b/lib/AsmParser/Lexer.l
index 7183e0e3ce2..ca6ee2cf73d 100644
--- a/lib/AsmParser/Lexer.l
+++ b/lib/AsmParser/Lexer.l
@@ -102,15 +102,22 @@ static double HexToFP(const char *Buffer) {
// UnEscapeLexed - Run through the specified buffer and change \xx codes to the
// appropriate character.
-char *UnEscapeLexed(char *Buffer) {
+char *UnEscapeLexed(char *Buffer, char* EndBuffer) {
char *BOut = Buffer;
for (char *BIn = Buffer; *BIn; ) {
- if (BIn[0] == '\\' && isxdigit(BIn[1]) && isxdigit(BIn[2])) {
- char Tmp = BIn[3]; BIn[3] = 0; // Terminate string
- *BOut = (char)strtol(BIn+1, 0, 16); // Convert to number
- BIn[3] = Tmp; // Restore character
- BIn += 3; // Skip over handled chars
- ++BOut;
+ if (BIn[0] == '\\') {
+ if (BIn < EndBuffer-1 && BIn[1] == '\\') {
+ *BOut++ = '\\'; // Two \ becomes one
+ BIn += 2;
+ } else if (BIn < EndBuffer-2 && isxdigit(BIn[1]) && isxdigit(BIn[2])) {
+ char Tmp = BIn[3]; BIn[3] = 0; // Terminate string
+ *BOut = (char)strtol(BIn+1, 0, 16); // Convert to number
+ BIn[3] = Tmp; // Restore character
+ BIn += 3; // Skip over handled chars
+ ++BOut;
+ } else {
+ *BOut++ = *BIn++;
+ }
} else {
*BOut++ = *BIn++;
}
@@ -326,28 +333,30 @@ shufflevector { RET_TOK(OtherOpVal, ShuffleVector, SHUFFLEVECTOR); }
}
{QuoteLabel} {
yytext[yyleng-2] = 0; // nuke colon, end quote
- const char* EndChar = UnEscapeLexed(yytext+1);
+ const char* EndChar = UnEscapeLexed(yytext+1, yytext+yyleng);
llvmAsmlval.StrVal =
new std::string(yytext+1, EndChar - yytext - 1);
return LABELSTR;
}
{StringConstant} { yytext[yyleng-1] = 0; // nuke end quote
- const char* EndChar = UnEscapeLexed(yytext+1);
+ const char* EndChar = UnEscapeLexed(yytext+1, yytext+yyleng);
llvmAsmlval.StrVal =
new std::string(yytext+1, EndChar - yytext - 1);
return STRINGCONSTANT;
}
{AtStringConstant} {
yytext[yyleng-1] = 0; // nuke end quote
- const char* EndChar = UnEscapeLexed(yytext+2);
+ const char* EndChar =
+ UnEscapeLexed(yytext+2, yytext+yyleng);
llvmAsmlval.StrVal =
new std::string(yytext+2, EndChar - yytext - 2);
return ATSTRINGCONSTANT;
}
{PctStringConstant} {
yytext[yyleng-1] = 0; // nuke end quote
- const char* EndChar = UnEscapeLexed(yytext+2);
+ const char* EndChar =
+ UnEscapeLexed(yytext+2, yytext+yyleng);
llvmAsmlval.StrVal =
new std::string(yytext+2, EndChar - yytext - 2);
return PCTSTRINGCONSTANT;