CVE-2026-46215
Analyzed
Analyzed - Analysis Complete
Race Condition in Linux Kernel DRM Handle Management
Publication date: 2026-05-28
Last updated on: 2026-06-10
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
drm: Set old handle to NULL before prime swap in change_handle
There was a potential race condition in change_handle. The ioctl
briefly had a single object with two idr entries; a concurrent
gem_close could delete the object and remove one of the handles
while leaving the other one dangling, which could subsequently
be dereferenced for a use-after-free.
To fix this, do the same dance that gem_close itself does.
(f6cd7daecff5 drm: Release driver references to handle before making it available again)
First idr_replace the old handle to NULL. Later, if the prime
operations are successful, actually close it.
create_tail required a similar dance to avoid a similar problem.
(bd46cece51a3 drm/gem: Fix race in drm_gem_handle_create_tail())
It idr_allocs the new handle with NULL, then swaps in the correct
object later to avoid races. We don't need to do that here, since
the only operations that could race are drm_prime, and
change_handle holds the prime lock for the entire duration.
v2: cleanups of error paths
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | 7.1 |
| linux | linux_kernel | 7.1 |
| linux | linux_kernel | From 6.18 (inc) to 6.18.32 (exc) |
| linux | linux_kernel | From 6.19 (inc) to 7.0.9 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-416 | The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer. |