From 49caa5e179e807c2b0977847d0afa9a2223109d7 Mon Sep 17 00:00:00 2001
From: Andrey Kleshchev <117672381+akleshchev@users.noreply.github.com>
Date: Tue, 30 Sep 2025 22:44:40 +0300
Subject: [PATCH] #4758 Extra logging to track discard 6

Plus clamped some values and preventing decode from starting

# Conflicts:
#	indra/newview/llviewertexture.cpp
---
 indra/llrender/llimagegl.cpp      |  3 ++-
 indra/newview/lltexturefetch.cpp  | 21 +++++++++++++++++----
 indra/newview/llviewertexture.cpp |  2 +-
 3 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/indra/llrender/llimagegl.cpp b/indra/llrender/llimagegl.cpp
index b1ba3b54c5..4f60946577 100644
--- a/indra/llrender/llimagegl.cpp
+++ b/indra/llrender/llimagegl.cpp
@@ -1548,7 +1548,7 @@ bool LLImageGL::createGLTexture(S32 discard_level, const LLImageRaw* imageraw, S
     if (discard_level < 0)
     {
         llassert(mCurrentDiscardLevel >= 0);
-        discard_level = mCurrentDiscardLevel;
+        discard_level = llmin(mCurrentDiscardLevel, MAX_DISCARD_LEVEL);
     }
 
     // Actual image width/height = raw image width/height * 2^discard_level
@@ -1648,6 +1648,7 @@ bool LLImageGL::createGLTexture(S32 discard_level, const U8* data_in, bool data_
         discard_level = mCurrentDiscardLevel;
     }
     discard_level = llclamp(discard_level, 0, (S32)mMaxDiscardLevel);
+    discard_level = llmin(discard_level, MAX_DISCARD_LEVEL);
 
     if (main_thread // <--- always force creation of new_texname when not on main thread ...
         && !defer_copy // <--- ... or defer copy is set
diff --git a/indra/newview/lltexturefetch.cpp b/indra/newview/lltexturefetch.cpp
index 334a62c02c..f4f960b8eb 100644
--- a/indra/newview/lltexturefetch.cpp
+++ b/indra/newview/lltexturefetch.cpp
@@ -1898,10 +1898,10 @@ bool LLTextureFetchWorker::doWork(S32 param)
             mHttpReplyOffset = 0;
 
             mLoadedDiscard = mRequestedDiscard;
-            if (mLoadedDiscard < 0)
+            if (mLoadedDiscard < 0 || (mLoadedDiscard > MAX_DISCARD_LEVEL && mFormattedImage->getCodec() == IMG_CODEC_J2C))
             {
                 LL_WARNS(LOG_TXT) << mID << " mLoadedDiscard is " << mLoadedDiscard
-                                  << ", should be >=0" << LL_ENDL;
+                                  << ", should be >=0 and <=" << MAX_DISCARD_LEVEL << LL_ENDL;
             }
             setState(DECODE_IMAGE);
             if (mWriteToCacheState != NOT_WRITE)
@@ -1963,14 +1963,27 @@ bool LLTextureFetchWorker::doWork(S32 param)
             LL_DEBUGS(LOG_TXT) << mID << " DECODE_IMAGE abort: mLoadedDiscard < 0" << LL_ENDL;
             return true;
         }
+
+        llassert_always(mFormattedImage.notNull());
+        S32 discard = mHaveAllData && mFormattedImage->getCodec() != IMG_CODEC_J2C ? 0 : mLoadedDiscard;
+        if (discard > MAX_DISCARD_LEVEL) // only warn for j2c
+        {
+            // We encode j2c with fixed amount of discard levels,
+            // Trying to decode beyound that will fail.
+            LL_WARNS(LOG_TXT) << "Decode entered with invalid discard. ID = " << mID << LL_ENDL;
+
+            //abort, don't decode
+            setState(DONE);
+            LL_DEBUGS(LOG_TXT) << mID << " DECODE_IMAGE abort: mLoadedDiscard > MAX_DISCARD_LEVEL" << LL_ENDL;
+            return true;
+        }
+
         mDecodeTimer.reset();
         mRawImage = NULL;
         mAuxImage = NULL;
-        llassert_always(mFormattedImage.notNull());
 
         // if we have the entire image data (and the image is not J2C), decode the full res image
         // DO NOT decode a higher res j2c than was requested.  This is a waste of time and memory.
-        S32 discard = mHaveAllData && mFormattedImage->getCodec() != IMG_CODEC_J2C ? 0 : mLoadedDiscard;
         mDecoded  = false;
         setState(DECODE_IMAGE_UPDATE);
         LL_DEBUGS(LOG_TXT) << mID << ": Decoding. Bytes: " << mFormattedImage->getDataSize() << " Discard: " << discard
diff --git a/indra/newview/llviewertexture.cpp b/indra/newview/llviewertexture.cpp
index 2d58f624e3..9567f55efa 100644
--- a/indra/newview/llviewertexture.cpp
+++ b/indra/newview/llviewertexture.cpp
@@ -2188,7 +2188,7 @@ bool LLViewerFetchedTexture::updateFetch()
         static LLCachedControl<U32> sTextureDiscardLevel(gSavedSettings, "TextureDiscardLevel");
         const U32 override_tex_discard_level = sTextureDiscardLevel();
         // </FS:Ansariel>
-        if (override_tex_discard_level != 0)
+        if (override_tex_discard_level != 0 && override_tex_discard_level <= MAX_DISCARD_LEVEL)
         {
             desired_discard = override_tex_discard_level;
         }