[Intel-gfx] [PATCH] drm/i915/reset_stats: Only allow root to read reset_stats

[Antonio Argenziano]

Instead of returning a zero value for non root users, return an EPERM
error.

Signed-off-by: Antonio Argenziano <antonio.argenziano at intel.com>
Cc: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Michel Thierry <michel.thierry at intel.com>
---
 drivers/gpu/drm/i915/i915_drv.c         | 2 +-
 drivers/gpu/drm/i915/i915_gem_context.c | 9 ++++-----
 2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 6c8da9d20c33..23fb4c61163c 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -2817,7 +2817,7 @@ static const struct drm_ioctl_desc i915_ioctls[] = {
 	DRM_IOCTL_DEF_DRV(I915_GEM_CONTEXT_CREATE, i915_gem_context_create_ioctl, DRM_RENDER_ALLOW),
 	DRM_IOCTL_DEF_DRV(I915_GEM_CONTEXT_DESTROY, i915_gem_context_destroy_ioctl, DRM_RENDER_ALLOW),
 	DRM_IOCTL_DEF_DRV(I915_REG_READ, i915_reg_read_ioctl, DRM_RENDER_ALLOW),
-	DRM_IOCTL_DEF_DRV(I915_GET_RESET_STATS, i915_gem_context_reset_stats_ioctl, DRM_RENDER_ALLOW),
+	DRM_IOCTL_DEF_DRV(I915_GET_RESET_STATS, i915_gem_context_reset_stats_ioctl, DRM_RENDER_ALLOW|DRM_ROOT_ONLY),
 	DRM_IOCTL_DEF_DRV(I915_GEM_USERPTR, i915_gem_userptr_ioctl, DRM_RENDER_ALLOW),
 	DRM_IOCTL_DEF_DRV(I915_GEM_CONTEXT_GETPARAM, i915_gem_context_getparam_ioctl, DRM_RENDER_ALLOW),
 	DRM_IOCTL_DEF_DRV(I915_GEM_CONTEXT_SETPARAM, i915_gem_context_setparam_ioctl, DRM_RENDER_ALLOW),
diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 648e7536ff51..e6872bd8b754 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -842,6 +842,9 @@ int i915_gem_context_reset_stats_ioctl(struct drm_device *dev,
 	if (args->flags || args->pad)
 		return -EINVAL;
 
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
 	ret = -ENOENT;
 	rcu_read_lock();
 	ctx = __i915_gem_context_lookup_rcu(file->driver_priv, args->ctx_id);
@@ -855,11 +858,7 @@ int i915_gem_context_reset_stats_ioctl(struct drm_device *dev,
 	 * we should wrap the hangstats with a seqlock.
 	 */
 
-	if (capable(CAP_SYS_ADMIN))
-		args->reset_count = i915_reset_count(&dev_priv->gpu_error);
-	else
-		args->reset_count = 0;
-
+	args->reset_count = i915_reset_count(&dev_priv->gpu_error);
 	args->batch_active = atomic_read(&ctx->guilty_count);
 	args->batch_pending = atomic_read(&ctx->active_count);
 
-- 
2.14.2