drm/amd/amdgpu: ring debugfs is read in increments of 4 bytes

If a user tries to read a non-multiple of 4 bytes it would have
read until the end of the ring potentially crashing the user
task.

Signed-off-by: Tom St Denis <tom.stdenis@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
index 5491696ac827..942111517e40 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
@@ -383,7 +383,7 @@ static ssize_t amdgpu_debugfs_ring_read(struct file *f, char __user *buf,
         int r, i;
         uint32_t value, result, early[3];
 
-        if (*pos & 3)
+        if (*pos & 3 || size & 3)
                 return -EINVAL;
 
         result = 0;