Protect against modifying annotations with a negative line number or a line

number after the document end.

1 files changed, 26 insertions, 24 deletions

diff --git a/src/PerLine.cxx b/src/PerLine.cxx
index 7e716ccc0..0bdb60254 100644
--- a/src/PerLine.cxx
+++ b/src/PerLine.cxx
@@ -397,28 +397,28 @@ bool LineAnnotation::AnySet() const {
 }
 
 bool LineAnnotation::MultipleStyles(int line) const {
-	if (annotations.Length() && (line < annotations.Length()) && annotations[line])
+	if (annotations.Length() && (line >= 0) && (line < annotations.Length()) && annotations[line])
 		return reinterpret_cast<AnnotationHeader *>(annotations[line])->style == IndividualStyles;
 	else
 		return 0;
 }
 
 int LineAnnotation::Style(int line) {
-	if (annotations.Length() && (line < annotations.Length()) && annotations[line])
+	if (annotations.Length() && (line >= 0) && (line < annotations.Length()) && annotations[line])
 		return reinterpret_cast<AnnotationHeader *>(annotations[line])->style;
 	else
 		return 0;
 }
 
 const char *LineAnnotation::Text(int line) const {
-	if (annotations.Length() && (line < annotations.Length()) && annotations[line])
+	if (annotations.Length() && (line >= 0) && (line < annotations.Length()) && annotations[line])
 		return annotations[line]+sizeof(AnnotationHeader);
 	else
 		return 0;
 }
 
 const unsigned char *LineAnnotation::Styles(int line) const {
-	if (annotations.Length() && (line < annotations.Length()) && annotations[line] && MultipleStyles(line))
+	if (annotations.Length() && (line >= 0) && (line < annotations.Length()) && annotations[line] && MultipleStyles(line))
 		return reinterpret_cast<unsigned char *>(annotations[line] + sizeof(AnnotationHeader) + Length(line));
 	else
 		return 0;
@@ -432,7 +432,7 @@ static char *AllocateAnnotation(int length, int style) {
 }
 
 void LineAnnotation::SetText(int line, const char *text) {
-	if (text) {
+	if (text && (line >= 0)) {
 		annotations.EnsureLength(line+1);
 		int style = Style(line);
 		if (annotations[line]) {
@@ -445,7 +445,7 @@ void LineAnnotation::SetText(int line, const char *text) {
 		pah->lines = static_cast<short>(NumberLines(text));
 		memcpy(annotations[line]+sizeof(AnnotationHeader), text, pah->length);
 	} else {
-		if (annotations.Length() && (line < annotations.Length()) && annotations[line]) {
+		if (annotations.Length() && (line >= 0) && (line < annotations.Length()) && annotations[line]) {
 			delete []annotations[line];
 			annotations[line] = 0;
 		}
@@ -469,35 +469,37 @@ void LineAnnotation::SetStyle(int line, int style) {
 }
 
 void LineAnnotation::SetStyles(int line, const unsigned char *styles) {
-	annotations.EnsureLength(line+1);
-	if (!annotations[line]) {
-		annotations[line] = AllocateAnnotation(0, IndividualStyles);
-	} else {
-		AnnotationHeader *pahSource = reinterpret_cast<AnnotationHeader *>(annotations[line]);
-		if (pahSource->style != IndividualStyles) {
-			char *allocation = AllocateAnnotation(pahSource->length, IndividualStyles);
-			AnnotationHeader *pahAlloc = reinterpret_cast<AnnotationHeader *>(allocation);
-			pahAlloc->length = pahSource->length;
-			pahAlloc->lines = pahSource->lines;
-			memcpy(allocation + sizeof(AnnotationHeader), annotations[line] + sizeof(AnnotationHeader), pahSource->length);
-			delete []annotations[line];
-			annotations[line] = allocation;
+	if (line >= 0) {
+		annotations.EnsureLength(line+1);
+		if (!annotations[line]) {
+			annotations[line] = AllocateAnnotation(0, IndividualStyles);
+		} else {
+			AnnotationHeader *pahSource = reinterpret_cast<AnnotationHeader *>(annotations[line]);
+			if (pahSource->style != IndividualStyles) {
+				char *allocation = AllocateAnnotation(pahSource->length, IndividualStyles);
+				AnnotationHeader *pahAlloc = reinterpret_cast<AnnotationHeader *>(allocation);
+				pahAlloc->length = pahSource->length;
+				pahAlloc->lines = pahSource->lines;
+				memcpy(allocation + sizeof(AnnotationHeader), annotations[line] + sizeof(AnnotationHeader), pahSource->length);
+				delete []annotations[line];
+				annotations[line] = allocation;
+			}
 		}
+		AnnotationHeader *pah = reinterpret_cast<AnnotationHeader *>(annotations[line]);
+		pah->style = IndividualStyles;
+		memcpy(annotations[line] + sizeof(AnnotationHeader) + pah->length, styles, pah->length);
 	}
-	AnnotationHeader *pah = reinterpret_cast<AnnotationHeader *>(annotations[line]);
-	pah->style = IndividualStyles;
-	memcpy(annotations[line] + sizeof(AnnotationHeader) + pah->length, styles, pah->length);
 }
 
 int LineAnnotation::Length(int line) const {
-	if (annotations.Length() && (line < annotations.Length()) && annotations[line])
+	if (annotations.Length() && (line >= 0) && (line < annotations.Length()) && annotations[line])
 		return reinterpret_cast<AnnotationHeader *>(annotations[line])->length;
 	else
 		return 0;
 }
 
 int LineAnnotation::Lines(int line) const {
-	if (annotations.Length() && (line < annotations.Length()) && annotations[line])
+	if (annotations.Length() && (line >= 0) && (line < annotations.Length()) && annotations[line])
 		return reinterpret_cast<AnnotationHeader *>(annotations[line])->lines;
 	else
 		return 0;