Overview
About vulnerability
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.
Details
- Affected product:
- CentOS 6 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CloudLinux 6 ELS , Oracle Linux 6 ELS , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS
- Affected packages:
- kernel @ 2.6.32 (+7 more)
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.