Re: [PATCH] drm/i915: Fix error pointer dereference in i915_gem_do_execbuffer()

[Matthew Brost <matthew.brost@intel.com>]

On Tue, Nov 16, 2021 at 02:48:17PM +0300, Dan Carpenter wrote:
> Originally "out_fence" was set using out_fence = sync_file_create() but
> which returns NULL, but now it is set with out_fence = eb_requests_create()
> which returns error pointers.  The error path needs to be modified to
> avoid an Oops in the "goto err_request;" path.
> 
> Fixes: 544460c33821 ("drm/i915: Multi-BB execbuf")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Thanks for the fix. LGTM. With that:
Reviewed-by: Matthew Brost <matthew.brost@intel.com>

> ---
>  drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 1 +
>  2 files changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
> index 4d7da07442f2..9b24d9b5ade1 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
> @@ -3277,6 +3277,7 @@ i915_gem_do_execbuffer(struct drm_device *dev,
>  	out_fence = eb_requests_create(&eb, in_fence, out_fence_fd);
>  	if (IS_ERR(out_fence)) {
>  		err = PTR_ERR(out_fence);
> +		out_fence = NULL;
>  		if (eb.requests[0])
>  			goto err_request;
>  		else
> -- 
> 2.20.1
>