drm/prime: Fix use after free in mmap with drm_gem_ttm_mmap
drm_gem_ttm_mmap() drops a reference to the gem object on success. If
the gem object's refcount == 1 on entry to drm_gem_prime_mmap(), that
drop will free the gem object, and the subsequent drm_gem_object_get()
will be a UAF. Fix by grabbing a reference before calling the mmap
helper.
This issue was forseen when the reference dropping was adding in
commit 9786b65bc61ac ("drm/ttm: fix mmap refcounting"):
"For that to work properly the drm_gem_object_get() call in
drm_gem_ttm_mmap() must be moved so it happens before calling
obj->funcs->mmap(), otherwise the gem refcount would go down
to zero."
Metrics
Affected Vendors & Products
No advisories yet.
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
Tue, 07 Jan 2025 17:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| Metrics |
cvssV3_1
|
cvssV3_1
|
Mon, 04 Nov 2024 12:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-05-04T07:06:15.756Z
Reserved: 2024-03-25T09:12:14.117Z
Link: CVE-2021-47200
Updated: 2024-08-04T05:32:07.374Z
Status : Analyzed
Published: 2024-04-10T19:15:48.077
Modified: 2025-01-07T17:12:06.773
Link: CVE-2021-47200
OpenCVE Enrichment
No data.