SDL_image: Fixed potential buffer overflow in tRNS handling (c7258)

SDL Commits
1 
From c7258b810b520cfa6fdb14b17b509aa31bd70791 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Tue, 10 Mar 2026 10:32:13 -0700
Subject: [PATCH] Fixed potential buffer overflow in tRNS handling

Closes https://github.com/libsdl-org/SDL_image/pull/704

(cherry picked from commit 19cc7cdb1e30554d3bf4f4526a21a8f57b861279)
---
 src/IMG_libpng.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/IMG_libpng.c b/src/IMG_libpng.c
index 365565a6..08ac6a12 100644
--- a/src/IMG_libpng.c
+++ b/src/IMG_libpng.c
@@ -1341,7 +1341,7 @@ bool IMG_CreateAPNGAnimationDecoder(IMG_AnimationDecoder *decoder, SDL_Propertie
 
         } else if (SDL_memcmp(chunk_type, "tRNS", 4) == 0) {
             if (ctx->palette) {
-                int num_trans = SDL_min((int)chunk_size, ctx->palette->ncolors);
+                int num_trans = SDL_min((int)chunk_length, ctx->palette->ncolors);
                 for (int i = 0; i < num_trans; i++) {
                     ctx->palette->colors[i].a = chunk_data[i];
                 }