From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Mon, 13 Feb 2017 13:02:07 +0000 (-0800)
Subject: 4.4-stable patches
X-Git-Tag: v4.9.10~1
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=7ad41f45ebbde2f2126106525c1f4c1fffba4308;p=thirdparty%2Fkernel%2Fstable-queue.git

4.4-stable patches

added patches:
	drm-i915-fix-use-after-free-in-page_flip_completed.patch
---

diff --git a/queue-4.4/drm-i915-fix-use-after-free-in-page_flip_completed.patch b/queue-4.4/drm-i915-fix-use-after-free-in-page_flip_completed.patch
new file mode 100644
index 00000000000..adc37c7a2be
--- /dev/null
+++ b/queue-4.4/drm-i915-fix-use-after-free-in-page_flip_completed.patch
@@ -0,0 +1,67 @@
+From 5351fbb1bf1413f6024892093528280769ca852f Mon Sep 17 00:00:00 2001
+From: Andrey Ryabinin <aryabinin@virtuozzo.com>
+Date: Thu, 26 Jan 2017 17:32:11 +0300
+Subject: drm/i915: fix use-after-free in page_flip_completed()
+
+From: Andrey Ryabinin <aryabinin@virtuozzo.com>
+
+commit 5351fbb1bf1413f6024892093528280769ca852f upstream.
+
+page_flip_completed() dereferences 'work' variable after executing
+queue_work(). This is not safe as the 'work' item might be already freed
+by queued work:
+
+    BUG: KASAN: use-after-free in page_flip_completed+0x3ff/0x490 at addr ffff8803dc010f90
+    Call Trace:
+     __asan_report_load8_noabort+0x59/0x80
+     page_flip_completed+0x3ff/0x490
+     intel_finish_page_flip_mmio+0xe3/0x130
+     intel_pipe_handle_vblank+0x2d/0x40
+     gen8_irq_handler+0x4a7/0xed0
+     __handle_irq_event_percpu+0xf6/0x860
+     handle_irq_event_percpu+0x6b/0x160
+     handle_irq_event+0xc7/0x1b0
+     handle_edge_irq+0x1f4/0xa50
+     handle_irq+0x41/0x70
+     do_IRQ+0x9a/0x200
+     common_interrupt+0x89/0x89
+
+    Freed:
+     kfree+0x113/0x4d0
+     intel_unpin_work_fn+0x29a/0x3b0
+     process_one_work+0x79e/0x1b70
+     worker_thread+0x611/0x1460
+     kthread+0x241/0x3a0
+     ret_from_fork+0x27/0x40
+
+Move queue_work() after	trace_i915_flip_complete() to fix this.
+
+Fixes: e5510fac98a7 ("drm/i915: add tracepoints for flip requests & completions")
+Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
+Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
+Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
+Link: http://patchwork.freedesktop.org/patch/msgid/20170126143211.24013-1-aryabinin@virtuozzo.com
+(cherry picked from commit 05c41f926fcc7ef838c80a6a99d84f67b4e0b824)
+Signed-off-by: Jani Nikula <jani.nikula@intel.com>
+Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/gpu/drm/i915/intel_display.c |    4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/drivers/gpu/drm/i915/intel_display.c
++++ b/drivers/gpu/drm/i915/intel_display.c
+@@ -3948,10 +3948,10 @@ static void page_flip_completed(struct i
+ 	drm_crtc_vblank_put(&intel_crtc->base);
+ 
+ 	wake_up_all(&dev_priv->pending_flip_queue);
+-	queue_work(dev_priv->wq, &work->work);
+-
+ 	trace_i915_flip_complete(intel_crtc->plane,
+ 				 work->pending_flip_obj);
++
++	queue_work(dev_priv->wq, &work->work);
+ }
+ 
+ void intel_crtc_wait_for_pending_flips(struct drm_crtc *crtc)
diff --git a/queue-4.4/series b/queue-4.4/series
index ec88aacca9b..424d9c41fb6 100644
--- a/queue-4.4/series
+++ b/queue-4.4/series
@@ -17,3 +17,4 @@ scsi-mpt3sas-disable-aspm-for-mpi2-controllers.patch
 xen-netfront-delete-rx_refill_timer-in-xennet_disconnect_backend.patch
 alsa-seq-fix-race-at-creating-a-queue.patch
 alsa-seq-don-t-handle-loop-timeout-at-snd_seq_pool_done.patch
+drm-i915-fix-use-after-free-in-page_flip_completed.patch