In the Linux kernel, the following vulnerability has been resolved:
drm/panfrost: Fix GEM handle creation ref-counting
panfrost_gem_create_with_handle() previously returned a BO but with the only reference being from the handle, which user space could in theory guess and release, causing a use-after-free. Additionally if the call to panfrost_gem_mapping_get() in panfrost_ioctl_create_bo() failed then a(nother) reference on the BO was dropped.
The _create_with_handle() is a problematic pattern, so ditch it and instead create the handle in panfrost_ioctl_create_bo(). If the call to panfrost_gem_mapping_get() fails then this means that user space has indeed gone behind our back and freed the handle. In which case just return an error code.
| Software | From | Fixed in |
|---|---|---|
| linux / linux_kernel | 5.2 | 5.10.163 |
| linux / linux_kernel | 5.11 | 5.15.87 |
| linux / linux_kernel | 5.16 | 6.0.19 |
| linux / linux_kernel | 6.1 | 6.1.5 |
| linux / linux_kernel | 6.2-rc1 | 6.2-rc1.x |
| linux / linux_kernel | 6.2-rc2 | 6.2-rc2.x |