From 316dd5467bed9242088149fe92f3316ef4f235e9 Mon Sep 17 00:00:00 2001 From: Ted Kremenek Date: Fri, 15 Mar 2013 23:09:37 +0000 Subject: [PATCH] Fix buffer underrun (invalid read) triggered during diagnostic rendering. The test would overflow when computing '0 - 1'. I don't have a good testcase for this that does not depend on system headers. It did not trigger with preprocessed output, and I had trouble reducing the example. Fixes . Thanks to Michael Greiner for reporting this issue. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177201 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Frontend/TextDiagnostic.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/Frontend/TextDiagnostic.cpp b/lib/Frontend/TextDiagnostic.cpp index c972461241..ca4ad60c52 100644 --- a/lib/Frontend/TextDiagnostic.cpp +++ b/lib/Frontend/TextDiagnostic.cpp @@ -958,7 +958,7 @@ static void highlightRange(const CharSourceRange &R, // Pick the last non-whitespace column. if (EndColNo > map.getSourceLine().size()) EndColNo = map.getSourceLine().size(); - while (EndColNo-1 && + while (EndColNo && (map.getSourceLine()[EndColNo-1] == ' ' || map.getSourceLine()[EndColNo-1] == '\t')) EndColNo = map.startOfPreviousColumn(EndColNo); -- 2.40.0