Re: [PATCH v2] drm/vc4: fix krealloc() memory leak

[Joe Perches <joe@perches.com>]

On Sun, 2026-05-31 at 21:55 +0200, Alexander A. Klimov wrote:
> Don't just overwrite the original pointer passed to krealloc()
> with its return value without checking latter:
[]
> diff --git a/drivers/gpu/drm/vc4/vc4_validate_shaders.c b/drivers/gpu/drm/vc4/vc4_validate_shaders.c
[]
> @@ -290,15 +290,16 @@ static bool require_uniform_address_uniform(struct vc4_validated_shader_info *va
>  {
>  	uint32_t o = validated_shader->num_uniform_addr_offsets;
>  	uint32_t num_uniforms = validated_shader->uniforms_size / 4;
> +	u32 *offsets;
>  
> -	validated_shader->uniform_addr_offsets =
> -		krealloc(validated_shader->uniform_addr_offsets,
> -			 (o + 1) *
> -			 sizeof(*validated_shader->uniform_addr_offsets),
> -			 GFP_KERNEL);
> -	if (!validated_shader->uniform_addr_offsets)
> +	offsets = krealloc(validated_shader->uniform_addr_offsets,
> +			   (o + 1) *
> +			   sizeof(*validated_shader->uniform_addr_offsets),
> +			   GFP_KERNEL);

krealloc_array ?

> +	if (!offsets)
>  		return false;
>  
> +	validated_shader->uniform_addr_offsets = offsets;
>  	validated_shader->uniform_addr_offsets[o] = num_uniforms;
>  	validated_shader->num_uniform_addr_offsets++;