CVE - CVE-2022-48868

CVE-ID
CVE-2022-48868	Learn more at National Vulnerability Database (NVD) • CVSS Severity Rating • Fix Information • Vulnerable Software Versions • SCAP Mappings • CPE Information
Description
In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: Let probe fail when workqueue cannot be enabled The workqueue is enabled when the appropriate driver is loaded and disabled when the driver is removed. When the driver is removed it assumes that the workqueue was enabled successfully and proceeds to free allocations made during workqueue enabling. Failure during workqueue enabling does not prevent the driver from being loaded. This is because the error path within drv_enable_wq() returns success unless a second failure is encountered during the error path. By returning success it is possible to load the driver even if the workqueue cannot be enabled and allocations that do not exist are attempted to be freed during driver remove. Some examples of problematic flows: (a) idxd_dmaengine_drv_probe() -> drv_enable_wq() -> idxd_wq_request_irq(): In above flow, if idxd_wq_request_irq() fails then idxd_wq_unmap_portal() is called on error exit path, but drv_enable_wq() returns 0 because idxd_wq_disable() succeeds. The driver is thus loaded successfully. idxd_dmaengine_drv_remove()->drv_disable_wq()->idxd_wq_unmap_portal() Above flow on driver unload triggers the WARN in devm_iounmap() because the device resource has already been removed during error path of drv_enable_wq(). (b) idxd_dmaengine_drv_probe() -> drv_enable_wq() -> idxd_wq_request_irq(): In above flow, if idxd_wq_request_irq() fails then idxd_wq_init_percpu_ref() is never called to initialize the percpu counter, yet the driver loads successfully because drv_enable_wq() returns 0. idxd_dmaengine_drv_remove()->__idxd_wq_quiesce()->percpu_ref_kill(): Above flow on driver unload triggers a BUG when attempting to drop the initial ref of the uninitialized percpu ref: BUG: kernel NULL pointer dereference, address: 0000000000000010 Fix the drv_enable_wq() error path by returning the original error that indicates failure of workqueue enabling. This ensures that the probe fails when an error is encountered and the driver remove paths are only attempted when the workqueue was enabled successfully.
References
Note: References are provided for the convenience of the reader to help distinguish between vulnerabilities. The list is not intended to be complete.
MISC:https://git.kernel.org/stable/c/0f150134dd795ffcd60b798a85ab737d8d010fb7 URL:https://git.kernel.org/stable/c/0f150134dd795ffcd60b798a85ab737d8d010fb7 MISC:https://git.kernel.org/stable/c/99dc4520b74e7ca8e9dc9abe37a0b10b49467960 URL:https://git.kernel.org/stable/c/99dc4520b74e7ca8e9dc9abe37a0b10b49467960 MISC:https://git.kernel.org/stable/c/b51b75f0604f17c0f6f3b6f68f1a521a5cc6b04f URL:https://git.kernel.org/stable/c/b51b75f0604f17c0f6f3b6f68f1a521a5cc6b04f
Assigning CNA
kernel.org
Date Record Created
20240716	Disclaimer: The record creation date may reflect when the CVE ID was allocated or reserved, and does not necessarily indicate when this vulnerability was discovered, shared with the affected vendor, publicly disclosed, or updated in CVE.
Phase (Legacy)
Assigned (20240716)
Votes (Legacy)

Comments (Legacy)

Proposed (Legacy)
N/A
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