SDL_image: Fixed out of bound read in GIF decoder (38fdd)

SDL Commits
1 
From 38fdd07d43a01b604fffb7453bff3ae2e9fd339a Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Wed, 29 Apr 2026 08:18:09 -0700
Subject: [PATCH] Fixed out of bound read in GIF decoder

Fixes https://github.com/libsdl-org/SDL_image/issues/724

(cherry picked from commit e2b258927d11438cbf4ee55a5c4ff059a6e32d08)
(cherry picked from commit 2c02f371f55a2f74a291639d95761066ac2afff0)
---
 src/IMG_gif.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/IMG_gif.c b/src/IMG_gif.c
index 58667e94d..240bb7db1 100644
--- a/src/IMG_gif.c
+++ b/src/IMG_gif.c
@@ -469,8 +469,10 @@ GetCode(SDL_RWops *src, int code_size, int flag, State_t * state)
                 RWSetMsg("ran off the end of my bits");
             return -1;
         }
-        state->buf[0] = state->buf[state->last_byte - 2];
-        state->buf[1] = state->buf[state->last_byte - 1];
+        if (state->last_byte > 2) {
+            state->buf[0] = state->buf[state->last_byte - 2];
+            state->buf[1] = state->buf[state->last_byte - 1];
+        }
 
         if ((ret = GetDataBlock(src, &state->buf[2], state)) > 0)
             count = (unsigned char) ret;