drm/virtio: release the GEM object on virtio_gpu_vram_create() errors

Overview

In the Linux kernel, the following vulnerability has been resolved:

drm/virtio: release the GEM object on virtio_gpu_vram_create() errors

virtio_gpu_vram_create() frees the object with a bare kfree(vram) on both error paths after drm_gem_private_object_init() has run, and on the second one after drm_gem_create_mmap_offset() has linked obj->vma_node into the device's VMA offset manager. The freed object stays in that interval tree, so a later lookup or insertion walks freed memory, and the dma_resv and gpuva lock are never destroyed.

Call drm_gem_object_release() before kfree() on both paths.

Affected

• Linux >= 16845c5d540929d2f4dc845f11fbbb238e69170a < 977c2934064969503cabf98b1135d202ff62822e
• Linux >= 16845c5d540929d2f4dc845f11fbbb238e69170a < 5118b5fdf1eb9922a0cdd2afd25252081e2d4302
• Linux >= 16845c5d540929d2f4dc845f11fbbb238e69170a < a9bb8f8fd5694185c2f71ff91869afb300aab392
• Linux >= 16845c5d540929d2f4dc845f11fbbb238e69170a < 03bdbf182082694ab2add620d85f1a8b8f51bbbc
• Linux >= 16845c5d540929d2f4dc845f11fbbb238e69170a < 5c2cb3dd1447752b73d4f44d6b7434bc5259bfec
• Linux >= 16845c5d540929d2f4dc845f11fbbb238e69170a < 7c8deb77d05bcc8f79e255f669d82ec6ce91be12
• Linux >= 16845c5d540929d2f4dc845f11fbbb238e69170a < 036d28db1818af2f9d80db771f5405da84d7732d
• Linux 5.11

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.