CVE-2022-48792

In the Linux kernel, the following vulnerability has been resolved:

scsi: pm8001: Fix use-after-free for aborted SSP/STP sas_task

Currently a use-after-free may occur if a sas_task is aborted by the upper layer before we handle the I/O completion in mpi_ssp_completion() or mpi_sata_completion().

In this case, the following are the two steps in handling those I/O completions:

• Call complete() to inform the upper layer handler of completion of the I/O.

• Release driver resources associated with the sas_task in pm8001_ccb_task_free() call.

When complete() is called, the upper layer may free the sas_task. As such, we should not touch the associated sas_task afterwards, but we do so in the pm8001_ccb_task_free() call.

Fix by swapping the complete() and pm8001_ccb_task_free() calls ordering.

Weakness

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 Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.

Affected Software

Potential Mitigations

References

• https://git.kernel.org/stable/c/d9d93f32534a0a80a1c26bdb0746d90a7b19c2c2
• https://git.kernel.org/stable/c/df7abcaa1246e2537ab4016077b5443bb3c09378
• https://git.kernel.org/stable/c/f61f9fccb2cb4bb275674a79d638704db6bc2171
• https://git.kernel.org/stable/c/fe9ac3eaa2e387a5742b380b73a5a6bc237bf184
• https://git.kernel.org/stable/c/d9d93f32534a0a80a1c26bdb0746d90a7b19c2c2
• https://git.kernel.org/stable/c/df7abcaa1246e2537ab4016077b5443bb3c09378
• https://git.kernel.org/stable/c/f61f9fccb2cb4bb275674a79d638704db6bc2171
• https://git.kernel.org/stable/c/fe9ac3eaa2e387a5742b380b73a5a6bc237bf184