[PATCH 4.18 134/168] drm/amdgpu: fix error handling in amdgpu_cs_user_fence_chunk

From: Greg Kroah-Hartman
Date: Mon Oct 08 2018 - 14:52:14 EST


4.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: "Christian Kö" <christian.koenig@xxxxxxx>

[ Upstream commit 0165de983272d1fae0809ed9db47c46a412279bc ]

Slowly leaking memory one page at a time :)

Signed-off-by: Christian KÃnig <christian.koenig@xxxxxxx>
Reviewed-by: Andrey Grodzovsky <andrey.grodzovsky@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 23 +++++++++++++++--------
1 file changed, 15 insertions(+), 8 deletions(-)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -38,6 +38,7 @@ static int amdgpu_cs_user_fence_chunk(st
{
struct drm_gem_object *gobj;
unsigned long size;
+ int r;

gobj = drm_gem_object_lookup(p->filp, data->handle);
if (gobj == NULL)
@@ -49,20 +50,26 @@ static int amdgpu_cs_user_fence_chunk(st
p->uf_entry.tv.shared = true;
p->uf_entry.user_pages = NULL;

- size = amdgpu_bo_size(p->uf_entry.robj);
- if (size != PAGE_SIZE || (data->offset + 8) > size)
- return -EINVAL;
-
- *offset = data->offset;
-
drm_gem_object_put_unlocked(gobj);

+ size = amdgpu_bo_size(p->uf_entry.robj);
+ if (size != PAGE_SIZE || (data->offset + 8) > size) {
+ r = -EINVAL;
+ goto error_unref;
+ }
+
if (amdgpu_ttm_tt_get_usermm(p->uf_entry.robj->tbo.ttm)) {
- amdgpu_bo_unref(&p->uf_entry.robj);
- return -EINVAL;
+ r = -EINVAL;
+ goto error_unref;
}

+ *offset = data->offset;
+
return 0;
+
+error_unref:
+ amdgpu_bo_unref(&p->uf_entry.robj);
+ return r;
}

static int amdgpu_cs_parser_init(struct amdgpu_cs_parser *p, void *data)