In the Linux kernel, the following vulnerability has been resolved:
drbd: only clone bio if we have a backing device
Commit c347a787e34cb (drbd: set ->bi_bdev in drbd_req_new) moved a
bio_set_dev call (which has since been removed) to "earlier", from
drbd_request_prepare to drbd_req_new.
The problem is that this accesses device->ldev->backing_bdev, which is
not NULL-checked at this point. When we don't have an ldev (i.e. when
the DRBD device is diskless), this leads to a null pointer deref.
So, only allocate the private_bio if we actually have a disk. This is
also a small optimization, since we don't clone the bio to only to
immediately free it again in the diskless case.
drbd: only clone bio if we have a backing device
Commit c347a787e34cb (drbd: set ->bi_bdev in drbd_req_new) moved a
bio_set_dev call (which has since been removed) to "earlier", from
drbd_request_prepare to drbd_req_new.
The problem is that this accesses device->ldev->backing_bdev, which is
not NULL-checked at this point. When we don't have an ldev (i.e. when
the DRBD device is diskless), this leads to a null pointer deref.
So, only allocate the private_bio if we actually have a disk. This is
also a small optimization, since we don't clone the bio to only to
immediately free it again in the diskless case.
Metrics
Affected Vendors & Products
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Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Sat, 04 Oct 2025 16:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: drbd: only clone bio if we have a backing device Commit c347a787e34cb (drbd: set ->bi_bdev in drbd_req_new) moved a bio_set_dev call (which has since been removed) to "earlier", from drbd_request_prepare to drbd_req_new. The problem is that this accesses device->ldev->backing_bdev, which is not NULL-checked at this point. When we don't have an ldev (i.e. when the DRBD device is diskless), this leads to a null pointer deref. So, only allocate the private_bio if we actually have a disk. This is also a small optimization, since we don't clone the bio to only to immediately free it again in the diskless case. | |
| Title | drbd: only clone bio if we have a backing device | |
| References |
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-10-04T15:43:54.955Z
Reserved: 2025-10-04T15:39:19.465Z
Link: CVE-2022-50506
Vulnrichment
No data.
NVD
Status : Received
Published: 2025-10-04T16:15:47.850
Modified: 2025-10-04T16:15:47.850
Link: CVE-2022-50506
Redhat
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OpenCVE Enrichment
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