From 053a113ad8f853c398c0e268408bfdc280b23f11 Mon Sep 17 00:00:00 2001 From: Niklas Haas Date: Tue, 15 Jul 2025 12:46:11 +0200 Subject: [PATCH] avutil/hwcontext_vulkan: don't over-map buffers with prior padding If the image data is not at the start of the buffer allocation, such as when the buffer has padding before the image data, this function maps too much memory, since src_data + src_buf->size exceeds the buffer size. Fix this by subtracting the difference between the buffer start and the provided image data pointer from the size of the memory range to map. An easy way to reproduce this issue is using the vf_pad filter, which allocates image data buffers with a nonzero offset whenever padding is requested before the start of the image data. --- libavutil/vulkan.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/libavutil/vulkan.c b/libavutil/vulkan.c index f36f2bb7cf..04cc45ee05 100644 --- a/libavutil/vulkan.c +++ b/libavutil/vulkan.c @@ -1408,7 +1408,8 @@ int ff_vk_host_map_buffer(FFVulkanContext *s, AVBufferRef **dst, return AVERROR(ENOMEM); /* Add the offset at the start, which gets ignored */ - buffer_size = offs + src_buf->size; + const ptrdiff_t src_offset = src_data - src_buf->data; + buffer_size = offs + (src_buf->size - src_offset); buffer_size = FFALIGN(buffer_size, s->props.properties.limits.minMemoryMapAlignment); buffer_size = FFALIGN(buffer_size, s->hprops.minImportedHostPointerAlignment);