From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michel Thierry Subject: [PATCH] drm/i915: fix use-after-free in i915_drop_caches_set Date: Fri, 5 Sep 2014 17:53:23 +0100 Message-ID: <1409936003-9341-1-git-send-email-michel.thierry@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by gabe.freedesktop.org (Postfix) with ESMTP id 8E2E26E3F2 for ; Fri, 5 Sep 2014 09:53:30 -0700 (PDT) List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: intel-gfx@lists.freedesktop.org Cc: Daniel Vetter List-Id: intel-gfx@lists.freedesktop.org With the new vma/ppgtt lifetime rules, the ppgtt (vm) could be removed after i915_vma_unbind. Use list_for_each_entry_safe() to prevent this use-after-free. Found with gem_persistent_relocs and gem_evict_everything igt tests. Cc: Daniel Vetter Signed-off-by: Michel Thierry --- drivers/gpu/drm/i915/i915_debugfs.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index dd736c0..4b05cd8 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -3820,8 +3820,8 @@ i915_drop_caches_set(void *data, u64 val) struct drm_device *dev = data; struct drm_i915_private *dev_priv = dev->dev_private; struct drm_i915_gem_object *obj, *next; - struct i915_address_space *vm; - struct i915_vma *vma, *x; + struct i915_address_space *vm, *x; + struct i915_vma *vma, *y; int ret; DRM_DEBUG("Dropping caches: 0x%08llx\n", val); @@ -3842,8 +3842,9 @@ i915_drop_caches_set(void *data, u64 val) i915_gem_retire_requests(dev); if (val & DROP_BOUND) { - list_for_each_entry(vm, &dev_priv->vm_list, global_link) { - list_for_each_entry_safe(vma, x, &vm->inactive_list, + list_for_each_entry_safe(vm, x, &dev_priv->vm_list, + global_link) { + list_for_each_entry_safe(vma, y, &vm->inactive_list, mm_list) { if (vma->pin_count) continue; -- 2.0.3