drm/i915: Fix lock order reversal with cliprects and cmdbuf in non-DRI2 paths.
This introduces allocation in the batch submission path that wasn't there
previously, but these are compatibility paths so we care about simplicity
more than performance.
kernel.org bug #12419.
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Keith Packard <keithp@keithp.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index 6d21b9e..ae83fe0 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -356,7 +356,7 @@
return ret;
}
-static int i915_emit_cmds(struct drm_device * dev, int __user * buffer, int dwords)
+static int i915_emit_cmds(struct drm_device * dev, int *buffer, int dwords)
{
drm_i915_private_t *dev_priv = dev->dev_private;
int i;
@@ -370,8 +370,7 @@
for (i = 0; i < dwords;) {
int cmd, sz;
- if (DRM_COPY_FROM_USER_UNCHECKED(&cmd, &buffer[i], sizeof(cmd)))
- return -EINVAL;
+ cmd = buffer[i];
if ((sz = validate_cmd(cmd)) == 0 || i + sz > dwords)
return -EINVAL;
@@ -379,11 +378,7 @@
OUT_RING(cmd);
while (++i, --sz) {
- if (DRM_COPY_FROM_USER_UNCHECKED(&cmd, &buffer[i],
- sizeof(cmd))) {
- return -EINVAL;
- }
- OUT_RING(cmd);
+ OUT_RING(buffer[i]);
}
}
@@ -397,17 +392,13 @@
int
i915_emit_box(struct drm_device *dev,
- struct drm_clip_rect __user *boxes,
+ struct drm_clip_rect *boxes,
int i, int DR1, int DR4)
{
drm_i915_private_t *dev_priv = dev->dev_private;
- struct drm_clip_rect box;
+ struct drm_clip_rect box = boxes[i];
RING_LOCALS;
- if (DRM_COPY_FROM_USER_UNCHECKED(&box, &boxes[i], sizeof(box))) {
- return -EFAULT;
- }
-
if (box.y2 <= box.y1 || box.x2 <= box.x1 || box.y2 <= 0 || box.x2 <= 0) {
DRM_ERROR("Bad box %d,%d..%d,%d\n",
box.x1, box.y1, box.x2, box.y2);
@@ -460,7 +451,9 @@
}
static int i915_dispatch_cmdbuffer(struct drm_device * dev,
- drm_i915_cmdbuffer_t * cmd)
+ drm_i915_cmdbuffer_t *cmd,
+ struct drm_clip_rect *cliprects,
+ void *cmdbuf)
{
int nbox = cmd->num_cliprects;
int i = 0, count, ret;
@@ -476,13 +469,13 @@
for (i = 0; i < count; i++) {
if (i < nbox) {
- ret = i915_emit_box(dev, cmd->cliprects, i,
+ ret = i915_emit_box(dev, cliprects, i,
cmd->DR1, cmd->DR4);
if (ret)
return ret;
}
- ret = i915_emit_cmds(dev, (int __user *)cmd->buf, cmd->sz / 4);
+ ret = i915_emit_cmds(dev, cmdbuf, cmd->sz / 4);
if (ret)
return ret;
}
@@ -492,10 +485,10 @@
}
static int i915_dispatch_batchbuffer(struct drm_device * dev,
- drm_i915_batchbuffer_t * batch)
+ drm_i915_batchbuffer_t * batch,
+ struct drm_clip_rect *cliprects)
{
drm_i915_private_t *dev_priv = dev->dev_private;
- struct drm_clip_rect __user *boxes = batch->cliprects;
int nbox = batch->num_cliprects;
int i = 0, count;
RING_LOCALS;
@@ -511,7 +504,7 @@
for (i = 0; i < count; i++) {
if (i < nbox) {
- int ret = i915_emit_box(dev, boxes, i,
+ int ret = i915_emit_box(dev, cliprects, i,
batch->DR1, batch->DR4);
if (ret)
return ret;
@@ -626,6 +619,7 @@
master_priv->sarea_priv;
drm_i915_batchbuffer_t *batch = data;
int ret;
+ struct drm_clip_rect *cliprects = NULL;
if (!dev_priv->allow_batchbuffer) {
DRM_ERROR("Batchbuffer ioctl disabled\n");
@@ -637,17 +631,35 @@
RING_LOCK_TEST_WITH_RETURN(dev, file_priv);
- if (batch->num_cliprects && DRM_VERIFYAREA_READ(batch->cliprects,
- batch->num_cliprects *
- sizeof(struct drm_clip_rect)))
- return -EFAULT;
+ if (batch->num_cliprects < 0)
+ return -EINVAL;
+
+ if (batch->num_cliprects) {
+ cliprects = drm_calloc(batch->num_cliprects,
+ sizeof(struct drm_clip_rect),
+ DRM_MEM_DRIVER);
+ if (cliprects == NULL)
+ return -ENOMEM;
+
+ ret = copy_from_user(cliprects, batch->cliprects,
+ batch->num_cliprects *
+ sizeof(struct drm_clip_rect));
+ if (ret != 0)
+ goto fail_free;
+ }
mutex_lock(&dev->struct_mutex);
- ret = i915_dispatch_batchbuffer(dev, batch);
+ ret = i915_dispatch_batchbuffer(dev, batch, cliprects);
mutex_unlock(&dev->struct_mutex);
if (sarea_priv)
sarea_priv->last_dispatch = READ_BREADCRUMB(dev_priv);
+
+fail_free:
+ drm_free(cliprects,
+ batch->num_cliprects * sizeof(struct drm_clip_rect),
+ DRM_MEM_DRIVER);
+
return ret;
}
@@ -659,6 +671,8 @@
drm_i915_sarea_t *sarea_priv = (drm_i915_sarea_t *)
master_priv->sarea_priv;
drm_i915_cmdbuffer_t *cmdbuf = data;
+ struct drm_clip_rect *cliprects = NULL;
+ void *batch_data;
int ret;
DRM_DEBUG("i915 cmdbuffer, buf %p sz %d cliprects %d\n",
@@ -666,25 +680,50 @@
RING_LOCK_TEST_WITH_RETURN(dev, file_priv);
- if (cmdbuf->num_cliprects &&
- DRM_VERIFYAREA_READ(cmdbuf->cliprects,
- cmdbuf->num_cliprects *
- sizeof(struct drm_clip_rect))) {
- DRM_ERROR("Fault accessing cliprects\n");
- return -EFAULT;
+ if (cmdbuf->num_cliprects < 0)
+ return -EINVAL;
+
+ batch_data = drm_alloc(cmdbuf->sz, DRM_MEM_DRIVER);
+ if (batch_data == NULL)
+ return -ENOMEM;
+
+ ret = copy_from_user(batch_data, cmdbuf->buf, cmdbuf->sz);
+ if (ret != 0)
+ goto fail_batch_free;
+
+ if (cmdbuf->num_cliprects) {
+ cliprects = drm_calloc(cmdbuf->num_cliprects,
+ sizeof(struct drm_clip_rect),
+ DRM_MEM_DRIVER);
+ if (cliprects == NULL)
+ goto fail_batch_free;
+
+ ret = copy_from_user(cliprects, cmdbuf->cliprects,
+ cmdbuf->num_cliprects *
+ sizeof(struct drm_clip_rect));
+ if (ret != 0)
+ goto fail_clip_free;
}
mutex_lock(&dev->struct_mutex);
- ret = i915_dispatch_cmdbuffer(dev, cmdbuf);
+ ret = i915_dispatch_cmdbuffer(dev, cmdbuf, cliprects, batch_data);
mutex_unlock(&dev->struct_mutex);
if (ret) {
DRM_ERROR("i915_dispatch_cmdbuffer failed\n");
- return ret;
+ goto fail_batch_free;
}
if (sarea_priv)
sarea_priv->last_dispatch = READ_BREADCRUMB(dev_priv);
- return 0;
+
+fail_batch_free:
+ drm_free(batch_data, cmdbuf->sz, DRM_MEM_DRIVER);
+fail_clip_free:
+ drm_free(cliprects,
+ cmdbuf->num_cliprects * sizeof(struct drm_clip_rect),
+ DRM_MEM_DRIVER);
+
+ return ret;
}
static int i915_flip_bufs(struct drm_device *dev, void *data,