[PATCH v2] amdgpu: validate drm_amdgpu_gem_va addrs

[Chia-I Wu]

Validate drm_amdgpu_gem_va addrs in amdgpu_gem_va_ioctl.
amdgpu_vm_bo_replace_map no longer needs to validate (and its
validations were insufficient either).  amdgpu_vm_bo_map has internal
users and its validations are kept.

This is motivated by OOB access in amdgpu_vm_update_range when
offset_in_bo+map_size overflows.

Userspace (radeonsi and radv) seems fine as well.

v2: keep the validations in amdgpu_vm_bo_map

Fixes: 9f7eb5367d00 ("drm/amdgpu: actually use the VM map parameters")
Signed-off-by: Chia-I Wu <olvaffe at gmail.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c | 15 +++++++++++++++
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c  |  8 +-------
 2 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
index d8e683688daab..36d5adfdf0f69 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
@@ -681,6 +681,21 @@ int amdgpu_gem_va_ioctl(struct drm_device *dev, void *data,
 	uint64_t vm_size;
 	int r = 0;
 
+	if (args->va_address & ~PAGE_MASK || args->offset_in_bo & ~PAGE_MASK ||
+	    args->map_size & ~PAGE_MASK) {
+		dev_dbg(dev->dev, "unaligned va_address 0x%LX, offset_in_bo 0x%LX, or map_size 0x%LX\n",
+			args->va_address, args->offset_in_bo, args->map_size);
+		return -EINVAL;
+	}
+
+	if (args->map_size == 0 ||
+	    args->va_address + args->map_size < args->va_address ||
+	    args->offset_in_bo + args->map_size < args->offset_in_bo) {
+		dev_dbg(dev->dev, "invalid map_size 0x%LX (va_address 0x%LX, offset_in_bo 0x%LX)\n",
+			args->map_size, args->va_address, args->offset_in_bo);
+		return -EINVAL;
+	}
+
 	if (args->va_address < AMDGPU_VA_RESERVED_SIZE) {
 		dev_dbg(dev->dev,
 			"va_address 0x%LX is in reserved area 0x%LX\n",
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index b9441ab457ea7..6307baaa136cf 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -1501,15 +1501,9 @@ int amdgpu_vm_bo_replace_map(struct amdgpu_device *adev,
 	uint64_t eaddr;
 	int r;
 
-	/* validate the parameters */
-	if (saddr & ~PAGE_MASK || offset & ~PAGE_MASK ||
-	    size == 0 || size & ~PAGE_MASK)
-		return -EINVAL;
-
 	/* make sure object fit at this offset */
 	eaddr = saddr + size - 1;
-	if (saddr >= eaddr ||
-	    (bo && offset + size > amdgpu_bo_size(bo)) ||
+	if ((bo && offset + size > amdgpu_bo_size(bo)) ||
 	    (eaddr >= adev->vm_manager.max_pfn << AMDGPU_GPU_PAGE_SHIFT))
 		return -EINVAL;
 
-- 
2.40.1.698.g37aff9b760-goog