[Scummvm-git-logs] scummvm master -> f74395715e134a95cb956fa565ce15688a2df52e

[athrxx]

This automated email contains information about 2 new commits which have been
pushed to the 'scummvm' repo located at https://github.com/scummvm/scummvm .

Summary:
39a9f86820 KYRA: fix some MSVC warnings
f74395715e KYRA: (LOL) - fix invalid script stack access


Commit: 39a9f86820e07c09ed8792c277195057d0623df2
    https://github.com/scummvm/scummvm/commit/39a9f86820e07c09ed8792c277195057d0623df2
Author: athrxx (athrxx at scummvm.org)
Date: 2021-10-24T15:16:19+02:00

Commit Message:
KYRA: fix some MSVC warnings

Changed paths:
    engines/kyra/graphics/screen_mr.cpp
    engines/kyra/sound/sound.cpp


diff --git a/engines/kyra/graphics/screen_mr.cpp b/engines/kyra/graphics/screen_mr.cpp
index fb9f8c3a9f..5e0bba1dfe 100644
--- a/engines/kyra/graphics/screen_mr.cpp
+++ b/engines/kyra/graphics/screen_mr.cpp
@@ -184,7 +184,7 @@ void Big5Font::drawChar(uint16 c, byte *dst, int pitch, int) const {
 		glyphData = &_oneByteData[128];
 	} else if (c & 0x80) {
 		c = ((c & 0x7F00) >> 2) | (c & 0x3F);
-		assert(c * 28 < _twoByteDataSize);
+		assert(c * 28u < _twoByteDataSize);
 		glyphData = &_twoByteData[c * 28];
 		w = 15;
 	}
diff --git a/engines/kyra/sound/sound.cpp b/engines/kyra/sound/sound.cpp
index 11396be24c..ce46f4abaf 100644
--- a/engines/kyra/sound/sound.cpp
+++ b/engines/kyra/sound/sound.cpp
@@ -232,7 +232,7 @@ void MixedSoundDriver::haltTrack() {
 }
 
 bool MixedSoundDriver::isPlaying() const {
-	return _music->isPlaying() | _sfx->isPlaying();
+	return _music->isPlaying() || _sfx->isPlaying();
 }
 
 void MixedSoundDriver::playSoundEffect(uint16 track, uint8 volume) {


Commit: f74395715e134a95cb956fa565ce15688a2df52e
    https://github.com/scummvm/scummvm/commit/f74395715e134a95cb956fa565ce15688a2df52e
Author: athrxx (athrxx at scummvm.org)
Date: 2021-10-24T15:16:19+02:00

Commit Message:
KYRA: (LOL) - fix invalid script stack access

Thanks to benoit-pierre for finding this.

(see PR #3448, https://github.com/scummvm/scummvm/pull/3448)

I chose a different approach for the fix, since I wanted an easy way of detecting/preventing this for similiar cases and I also didn't want to have so much extra code in that particular script function.

Changed paths:
    engines/kyra/kyra_v1.h
    engines/kyra/script/script.h
    engines/kyra/script/script_lol.cpp


diff --git a/engines/kyra/kyra_v1.h b/engines/kyra/kyra_v1.h
index 591126db14..6c04e91338 100644
--- a/engines/kyra/kyra_v1.h
+++ b/engines/kyra/kyra_v1.h
@@ -300,6 +300,18 @@ protected:
 	int o1_blockOutWalkableRegion(EMCState *script);
 	int o1_playSoundEffect(EMCState *script);
 
+	// script debug
+#ifndef RELEASE_BUILD
+	int16 emcSafeReadStack(EMCState *s, int x, int line, const char *file) {
+		if (s->sp+x > EMCState::kStackLastEntry) {
+			//assert(sp+x < kStackSize);
+			warning("Invalid EMC stack read attempt from: '%s', line %d", file, line);
+			return 0;
+		}
+		return s->stack[s->sp+x];
+	}
+#endif
+
 	// items
 	int _mouseState;
 
diff --git a/engines/kyra/script/script.h b/engines/kyra/script/script.h
index 73f14b3f5c..7988a1d4de 100644
--- a/engines/kyra/script/script.h
+++ b/engines/kyra/script/script.h
@@ -60,7 +60,13 @@ struct EMCState {
 	int16 stack[kStackSize];  // VM stack
 };
 
+#ifdef RELEASE_BUILD
 #define stackPos(x) (script->stack[script->sp+x])
+#define safeStackPos(x) (script->sp+x < EMCState::kStackSize ? stackPos(x) : 0)
+#else
+#define stackPos(x) emcSafeReadStack(script, x, __LINE__, __FILE__)
+#define safeStackPos(x) stackPos(x)
+#endif
 #define stackPosString(x) ((const char *)&script->dataPtr->text[READ_BE_UINT16(&script->dataPtr->text[stackPos(x)<<1])])
 
 class Resource;
diff --git a/engines/kyra/script/script_lol.cpp b/engines/kyra/script/script_lol.cpp
index 15c8c365e4..a429f8eb73 100644
--- a/engines/kyra/script/script_lol.cpp
+++ b/engines/kyra/script/script_lol.cpp
@@ -1464,9 +1464,9 @@ int LoLEngine::olol_checkForCertainPartyMember(EMCState *script) {
 }
 
 int LoLEngine::olol_printMessage(EMCState *script) {
-	debugC(3, kDebugLevelScriptFuncs, "LoLEngine::olol_printMessage(%p) (%d, %d, %d, %d, %d, %d, %d, %d, %d, %d)", (const void *)script, stackPos(0), stackPos(1), stackPos(2), stackPos(3), stackPos(4), stackPos(5), stackPos(6), stackPos(7), stackPos(8), stackPos(9));
-	int snd = stackPos(2);
-	_txt->printMessage(stackPos(0), getLangString(stackPos(1)), stackPos(3), stackPos(4), stackPos(5), stackPos(6), stackPos(7), stackPos(8), stackPos(9));
+	debugC(3, kDebugLevelScriptFuncs, "LoLEngine::olol_printMessage(%p) (%d, %d, %d, %d, %d, %d, %d, %d, %d, %d)", (const void *)script, safeStackPos(0), safeStackPos(1), safeStackPos(2), safeStackPos(3), safeStackPos(4), safeStackPos(5), safeStackPos(6), safeStackPos(7), safeStackPos(8), safeStackPos(9));
+	int snd = safeStackPos(2);
+	_txt->printMessage(safeStackPos(0), getLangString(safeStackPos(1)), safeStackPos(3), safeStackPos(4), safeStackPos(5), safeStackPos(6), safeStackPos(7), safeStackPos(8), safeStackPos(9));
 
 	if (snd >= 0)
 		snd_playSoundEffect(snd, -1);