Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
RDMA/mlx4: Fix mis-use of RCU in mlx4_srq_event()
Sashiko points out the radix_tree itself is RCU safe, but nothing ever frees the mlx4_srq struct with RCU, and it isn’t even accessed within the RCU critical section. It also will crash if an event is delivered before the srq object is finished initializing.
Use the spinlock since it isn’t easy to make RCU work, use refcount_inc_not_zero() to protect against partially initialized objects, and order the refcount_set() to be after the srq is fully initialized.
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Debian 10 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- kernel @ 5.14.0 (+13 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| AlmaLinux 8 | Released |
107 kernels
|
| AlmaLinux 9 | Released |
109 kernels
|
| CentOS 7 | Released |
35 kernels
|
| CentOS 7 ELS | Planned | — |
| CentOS 7 plus | Released |
23 kernels
|
| CentOS 8 | Released |
33 kernels
|
| CloudLinux OS 7h | Released |
109 kernels
|
| CloudLinux OS 8 | Released |
104 kernels
|
| Oracle Linux 8 | Released |
129 kernels
|
| Oracle Linux 9 | Released |
109 kernels
|
| RHEL 7 | Released |
58 kernels
|
| RHEL 8 | Released |
124 kernels
|
| RHEL 9 | Released |
107 kernels
|
| Rocky Linux 8 | Released |
89 kernels
|
| Rocky Linux 9 | Released |
87 kernels
|