Re: [patch] drm/amdgpu: potential NULL dereference in debugfs code

[Christian König]

Am 12.10.2016 um 08:17 schrieb Dan Carpenter:

debugfs_create_file() returns NULL on error, it only returns error
pointers if debugfs isn't enabled in the config and we checked for that
earlier so it can't happen.

Fixes: 4f4824b55650 ('drm/amd/amdgpu: Convert ring debugfs entries to binary')
Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>

Reviewed-by: Christian König <christian.koe...@amd.com>.

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
index 85aeb0a..8d16eaf 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
@@ -371,8 +371,8 @@ static int amdgpu_debugfs_ring_init(struct amdgpu_device 
*adev,
        ent = debugfs_create_file(name,
                                  S_IFREG | S_IRUGO, root,
                                  ring, &amdgpu_debugfs_ring_fops);
-       if (IS_ERR(ent))
-               return PTR_ERR(ent);
+       if (!ent)
+               return -ENOMEM;

i_size_write(ent->d_inode, ring->ring_size + 12);

        ring->ent = ent;