diff options
author | Pan Bian <bianpan2016@163.com> | 2019-11-06 15:31:07 +0800 |
---|---|---|
committer | Zhenyu Wang <zhenyuw@linux.intel.com> | 2019-11-08 11:04:07 +0800 |
commit | 41d931459b53e32c67a1f8838d1e6826a69ee745 (patch) | |
tree | a80848e715fb2521ce30d97e7036762d2eb65976 /drivers/gpu/drm/i915/gvt | |
parent | ee2c5ef8a9d640ee1617ec97b84fe2f634284e51 (diff) | |
download | linux-41d931459b53e32c67a1f8838d1e6826a69ee745.tar.gz linux-41d931459b53e32c67a1f8838d1e6826a69ee745.tar.bz2 linux-41d931459b53e32c67a1f8838d1e6826a69ee745.zip |
drm/i915/gvt: fix dropping obj reference twice
The reference count of obj will be decremented twice if error occurs
in dma_buf_fd(). Additionally, attempting to read the reference count of
obj after dropping reference may lead to a use after free bug. Here, we
drop obj's reference until it is not used.
Fixes: e546e281d33d ("drm/i915/gvt: Dmabuf support for GVT-g")
Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Diffstat (limited to 'drivers/gpu/drm/i915/gvt')
-rw-r--r-- | drivers/gpu/drm/i915/gvt/dmabuf.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/gpu/drm/i915/gvt/dmabuf.c b/drivers/gpu/drm/i915/gvt/dmabuf.c index 13044c027f27..4bfaefdf548d 100644 --- a/drivers/gpu/drm/i915/gvt/dmabuf.c +++ b/drivers/gpu/drm/i915/gvt/dmabuf.c @@ -498,8 +498,6 @@ int intel_vgpu_get_dmabuf(struct intel_vgpu *vgpu, unsigned int dmabuf_id) goto out_free_gem; } - i915_gem_object_put(obj); - ret = dma_buf_fd(dmabuf, DRM_CLOEXEC | DRM_RDWR); if (ret < 0) { gvt_vgpu_err("create dma-buf fd failed ret:%d\n", ret); @@ -524,6 +522,8 @@ int intel_vgpu_get_dmabuf(struct intel_vgpu *vgpu, unsigned int dmabuf_id) file_count(dmabuf->file), kref_read(&obj->base.refcount)); + i915_gem_object_put(obj); + return dmabuf_fd; out_free_dmabuf: |