Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
bus: fsl-mc: fix double-free on mc_dev
The blamed commit tried to simplify how the deallocations are done but, in the process, introduced a double-free on the mc_dev variable.
In case the MC device is a DPRC, a new mc_bus is allocated and the mc_dev variable is just a reference to one of its fields. In this circumstance, on the error path only the mc_bus should be freed.
This commit introduces back the following checkpatch warning which is a false-positive.
WARNING: kfree(NULL) is safe and this check is probably not required
-
if (mc_bus) -
kfree(mc_bus);
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Oracle Linux 7 ELS , TuxCare 9.6 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- kernel @ 5.14.0 (+8 more)
In the Linux kernel, the following vulnerability has been resolved:
bus: fsl-mc: fix double-free on mc_dev
The blamed commit tried to simplify how the deallocations are done but, in the process, introduced a double-free on the mc_dev variable.
In case the MC device is a DPRC, a new mc_bus is allocated and the mc_dev variable is just a reference to one of its fields. In this circumstance, on the error path only the mc_bus should be freed.
This commit introduces back the following checkpatch warning which is a false-positive.
WARNING: kfree(NULL) is safe and this check is probably not required
-
if (mc_bus) -
kfree(mc_bus);