diff --git a/libavcodec/ffv1.c b/libavcodec/ffv1.c
index 5b52849400..1c580c3b49 100644
--- a/libavcodec/ffv1.c
+++ b/libavcodec/ffv1.c
@@ -119,7 +119,7 @@ av_cold int ff_ffv1_init_slice_contexts(FFV1Context *f)
 
     av_assert0(max_slice_count > 0);
 
-    for (i = 0; i < max_slice_count; i++) {
+    for (i = 0; i < max_slice_count;) {
         int sx          = i % f->num_h_slices;
         int sy          = i / f->num_h_slices;
         int sxs         = f->avctx->width  *  sx      / f->num_h_slices;
@@ -131,7 +131,7 @@ av_cold int ff_ffv1_init_slice_contexts(FFV1Context *f)
         if (!fs)
             goto memfail;
 
-        f->slice_context[i] = fs;
+        f->slice_context[i++] = fs;
         memcpy(fs, f, sizeof(*fs));
         memset(fs->rc_stat2, 0, sizeof(fs->rc_stat2));
 
@@ -144,22 +144,14 @@ av_cold int ff_ffv1_init_slice_contexts(FFV1Context *f)
                                       sizeof(*fs->sample_buffer));
         fs->sample_buffer32 = av_malloc_array((fs->width + 6), 3 * MAX_PLANES *
                                         sizeof(*fs->sample_buffer32));
-        if (!fs->sample_buffer || !fs->sample_buffer32) {
-            av_freep(&fs->sample_buffer);
-            av_freep(&fs->sample_buffer32);
-            av_freep(&f->slice_context[i]);
+        if (!fs->sample_buffer || !fs->sample_buffer32)
             goto memfail;
-        }
     }
     f->max_slice_count = max_slice_count;
     return 0;
 
 memfail:
-    while(--i >= 0) {
-        av_freep(&f->slice_context[i]->sample_buffer);
-        av_freep(&f->slice_context[i]->sample_buffer32);
-        av_freep(&f->slice_context[i]);
-    }
+    f->max_slice_count = i;
     return AVERROR(ENOMEM);
 }