drm/msm: validate flags, etc
After reading a nice article on LWN[1], I went back and double checked
my handling of invalid-input checking. Turns out there were a couple
places I had missed.
Since the driver is fairly young, and the devices it supports are really
only just barely usable for basic stuff (serial console) with an
upstream kernel, I think we should fix this now and revert specific
parts of this patch later in the unlikely event that a regression is
reported.
[1] https://lwn.net/Articles/588444/
Signed-off-by: Rob Clark <robdclark@gmail.com>
diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index 7a7421f..f9de156 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -664,6 +664,12 @@
struct drm_file *file)
{
struct drm_msm_gem_new *args = data;
+
+ if (args->flags & ~MSM_BO_FLAGS) {
+ DRM_ERROR("invalid flags: %08x\n", args->flags);
+ return -EINVAL;
+ }
+
return msm_gem_new_handle(dev, file, args->size,
args->flags, &args->handle);
}
@@ -677,6 +683,11 @@
struct drm_gem_object *obj;
int ret;
+ if (args->op & ~MSM_PREP_FLAGS) {
+ DRM_ERROR("invalid op: %08x\n", args->op);
+ return -EINVAL;
+ }
+
obj = drm_gem_object_lookup(dev, file, args->handle);
if (!obj)
return -ENOENT;
@@ -731,7 +742,14 @@
struct drm_file *file)
{
struct drm_msm_wait_fence *args = data;
- return msm_wait_fence_interruptable(dev, args->fence, &TS(args->timeout));
+
+ if (args->pad) {
+ DRM_ERROR("invalid pad: %08x\n", args->pad);
+ return -EINVAL;
+ }
+
+ return msm_wait_fence_interruptable(dev, args->fence,
+ &TS(args->timeout));
}
static const struct drm_ioctl_desc msm_ioctls[] = {
diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c
index 5423e91..1f1f4cf 100644
--- a/drivers/gpu/drm/msm/msm_gem_submit.c
+++ b/drivers/gpu/drm/msm/msm_gem_submit.c
@@ -23,7 +23,6 @@
* Cmdstream submission:
*/
-#define BO_INVALID_FLAGS ~(MSM_SUBMIT_BO_READ | MSM_SUBMIT_BO_WRITE)
/* make sure these don't conflict w/ MSM_SUBMIT_BO_x */
#define BO_VALID 0x8000
#define BO_LOCKED 0x4000
@@ -77,7 +76,7 @@
goto out_unlock;
}
- if (submit_bo.flags & BO_INVALID_FLAGS) {
+ if (submit_bo.flags & ~MSM_SUBMIT_BO_FLAGS) {
DRM_ERROR("invalid flags: %x\n", submit_bo.flags);
ret = -EINVAL;
goto out_unlock;
@@ -369,6 +368,18 @@
goto out;
}
+ /* validate input from userspace: */
+ switch (submit_cmd.type) {
+ case MSM_SUBMIT_CMD_BUF:
+ case MSM_SUBMIT_CMD_IB_TARGET_BUF:
+ case MSM_SUBMIT_CMD_CTX_RESTORE_BUF:
+ break;
+ default:
+ DRM_ERROR("invalid type: %08x\n", submit_cmd.type);
+ ret = -EINVAL;
+ goto out;
+ }
+
ret = submit_bo(submit, submit_cmd.submit_idx,
&msm_obj, &iova, NULL);
if (ret)
diff --git a/include/uapi/drm/msm_drm.h b/include/uapi/drm/msm_drm.h
index bf91a78..0664c31 100644
--- a/include/uapi/drm/msm_drm.h
+++ b/include/uapi/drm/msm_drm.h
@@ -70,6 +70,12 @@
#define MSM_BO_WC 0x00020000
#define MSM_BO_UNCACHED 0x00040000
+#define MSM_BO_FLAGS (MSM_BO_SCANOUT | \
+ MSM_BO_GPU_READONLY | \
+ MSM_BO_CACHED | \
+ MSM_BO_WC | \
+ MSM_BO_UNCACHED)
+
struct drm_msm_gem_new {
uint64_t size; /* in */
uint32_t flags; /* in, mask of MSM_BO_x */
@@ -86,6 +92,8 @@
#define MSM_PREP_WRITE 0x02
#define MSM_PREP_NOSYNC 0x04
+#define MSM_PREP_FLAGS (MSM_PREP_READ | MSM_PREP_WRITE | MSM_PREP_NOSYNC)
+
struct drm_msm_gem_cpu_prep {
uint32_t handle; /* in */
uint32_t op; /* in, mask of MSM_PREP_x */
@@ -153,6 +161,9 @@
*/
#define MSM_SUBMIT_BO_READ 0x0001
#define MSM_SUBMIT_BO_WRITE 0x0002
+
+#define MSM_SUBMIT_BO_FLAGS (MSM_SUBMIT_BO_READ | MSM_SUBMIT_BO_WRITE)
+
struct drm_msm_gem_submit_bo {
uint32_t flags; /* in, mask of MSM_SUBMIT_BO_x */
uint32_t handle; /* in, GEM handle */
