avcodec/imgconvert: fix possible null pointer dereference

regression since 354b26a394
7 years ago · 8c2c97403b
parent 4b736bc921
commit 8c2c97403b
1 changed files with 3 additions and 2 deletions
--- a/libavcodec/imgconvert.c
+++ b/libavcodec/imgconvert.c
@ -72,11 +72,12 @@ enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *p
    int loss;

    for (i=0; pix_fmt_list[i] != AV_PIX_FMT_NONE; i++) {
-        loss = *loss_ptr;
+        loss = loss_ptr ? *loss_ptr : 0;
        best = avcodec_find_best_pix_fmt_of_2(best, pix_fmt_list[i], src_pix_fmt, has_alpha, &loss);
    }

-    *loss_ptr = loss;
+    if (loss_ptr)
+        *loss_ptr = loss;
    return best;
 }