Description
In the Linux kernel, the following vulnerability has been resolved: Revert "drm/gem-dma: Use dma_buf from GEM object instance" This reverts commit e8afa1557f4f963c9a511bd2c6074a941c308685. The dma_buf field in struct drm_gem_object is not stable over the object instance's lifetime. The field becomes NULL when user space releases the final GEM handle on the buffer object. This resulted in a NULL-pointer deref. Workarounds in commit 5307dce878d4 ("drm/gem: Acquire references on GEM handles for framebuffers") and commit f6bfc9afc751 ("drm/framebuffer: Acquire internal references on GEM handles") only solved the problem partially. They especially don't work for buffer objects without a DRM framebuffer associated. Hence, this revert to going back to using .import_attach->dmabuf. v3: - cc stable
Product status
e8afa1557f4f963c9a511bd2c6074a941c308685 before e7bdb3104a2f71ec1439d37f8e6e2f201dbcd7cf
e8afa1557f4f963c9a511bd2c6074a941c308685 before 1918e79be908b8a2c8757640289bc196c14d928a
6.15
Any version before 6.15
6.15.9
6.16
References
git.kernel.org/...c/e7bdb3104a2f71ec1439d37f8e6e2f201dbcd7cf
git.kernel.org/...c/1918e79be908b8a2c8757640289bc196c14d928a
