1 files changed, 46 insertions, 31 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
index aca1a8045afa..ab7ccfaea22a 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
@@ -121,6 +121,20 @@ static int  amdgpu_debugfs_process_reg_op(bool read, struct file *f,
 
 	*pos &= (1UL << 22) - 1;
 
+	if (size > PAGE_SIZE)
+		return -EINVAL;
+
+	/*
+	 * Access the user buffer only while none of the locks below are held:
+	 * a fault takes mmap_lock, and grbm_idx_mutex and srbm_mutex nest
+	 * inside it.
+	 */
+	u32 *data __free(kfree) = kmalloc(size, GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+	if (!read && copy_from_user(data, buf, size))
+		return -EFAULT;
+
 	r = pm_runtime_get_sync(adev_to_drm(adev)->dev);
 	if (r < 0) {
 		pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
@@ -152,28 +166,16 @@ static int  amdgpu_debugfs_process_reg_op(bool read, struct file *f,
 		mutex_lock(&adev->pm.mutex);
 
 	while (size) {
-		uint32_t value;
-
-		if (read) {
-			value = RREG32(*pos >> 2);
-			r = put_user(value, (uint32_t *)buf);
-		} else {
-			r = get_user(value, (uint32_t *)buf);
-			if (!r)
-				amdgpu_mm_wreg_mmio_rlc(adev, *pos >> 2, value, 0);
-		}
-		if (r) {
-			result = r;
-			goto end;
-		}
+		if (read)
+			data[result >> 2] = RREG32(*pos >> 2);
+		else
+			amdgpu_mm_wreg_mmio_rlc(adev, *pos >> 2, data[result >> 2], 0);
 
 		result += 4;
-		buf += 4;
 		*pos += 4;
 		size -= 4;
 	}
 
-end:
 	if (use_bank) {
 		amdgpu_gfx_select_se_sh(adev, 0xffffffff, 0xffffffff, 0xffffffff, 0);
 		mutex_unlock(&adev->grbm_idx_mutex);
@@ -188,6 +190,10 @@ end:
 	pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
 
 	amdgpu_virt_disable_access_debugfs(adev);
+
+	if (read && copy_to_user(buf, data, result))
+		return -EFAULT;
+
 	return result;
 }
 
@@ -238,11 +244,24 @@ static ssize_t amdgpu_debugfs_regs2_op(struct file *f, char __user *buf, u32 off
 	struct amdgpu_device *adev = rd->adev;
 	ssize_t result = 0;
 	int r;
-	uint32_t value;
 
 	if (size & 0x3 || offset & 0x3)
 		return -EINVAL;
 
+	if (size > PAGE_SIZE)
+		return -EINVAL;
+
+	/*
+	 * Access the user buffer only while none of the locks below are held:
+	 * a fault takes mmap_lock, and grbm_idx_mutex and srbm_mutex nest
+	 * inside it.
+	 */
+	u32 *data __free(kfree) = kmalloc(size, GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+	if (write_en && copy_from_user(data, buf, size))
+		return -EFAULT;
+
 	r = pm_runtime_get_sync(adev_to_drm(adev)->dev);
 	if (r < 0) {
 		pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
@@ -281,24 +300,16 @@ static ssize_t amdgpu_debugfs_regs2_op(struct file *f, char __user *buf, u32 off
 		mutex_lock(&adev->pm.mutex);
 
 	while (size) {
-		if (!write_en) {
-			value = RREG32(offset >> 2);
-			r = put_user(value, (uint32_t *)buf);
-		} else {
-			r = get_user(value, (uint32_t *)buf);
-			if (!r)
-				amdgpu_mm_wreg_mmio_rlc(adev, offset >> 2, value, rd->id.xcc_id);
-		}
-		if (r) {
-			result = r;
-			goto end;
-		}
+		if (!write_en)
+			data[result >> 2] = RREG32(offset >> 2);
+		else
+			amdgpu_mm_wreg_mmio_rlc(adev, offset >> 2, data[result >> 2],
+						rd->id.xcc_id);
 		offset += 4;
 		size -= 4;
 		result += 4;
-		buf += 4;
 	}
-end:
+
 	if (rd->id.use_grbm) {
 		amdgpu_gfx_select_se_sh(adev, 0xffffffff, 0xffffffff, 0xffffffff, rd->id.xcc_id);
 		mutex_unlock(&adev->grbm_idx_mutex);
@@ -317,6 +328,10 @@ end:
 	pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
 
 	amdgpu_virt_disable_access_debugfs(adev);
+
+	if (!write_en && copy_to_user(buf, data, result))
+		return -EFAULT;
+
 	return result;
 }