Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
perf: Reject exited events as group leaders
perf_event_remove_on_exec() sets remove-on-exec events to the EXIT state and detaches their group relationships. The event’s file descriptor can remain open, however, and perf_event_open() currently accepts that event as a group leader because its early validation rejects only REVOKED and DEAD events.
A new sibling can consequently be linked to the detached leader. When the leader is closed, perf_group_detach() observes that its PERF_ATTACH_GROUP bit is already clear and skips the new sibling. The sibling then retains a group_leader pointer to the freed event.
Reject group leaders in the EXIT state. Perform the check while holding the shared context mutex so that an exec in the target task cannot detach the leader between validation and group attachment.
[peterz: make the earlier test fully consistent]
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 7 ELS , Debian 10 ELS , Oracle Linux 6 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU
- Affected packages:
- linux @ 4.19.0 (+12 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| AlmaLinux 10 | Released |
70 kernels
|
| AlmaLinux 8 | Released |
120 kernels
|
| CloudLinux OS 7h | Released |
98 kernels
|
| CloudLinux OS 8 | Released |
96 kernels
|
| Debian 13 | Planned | — |
| Oracle Linux 10 | Released |
54 kernels
|
| Oracle Linux 8 | Released |
113 kernels
|
| RHEL 10 | Released |
71 kernels
|
| RHEL 8 | Released |
113 kernels
|
| RHEL 9 | Planned | — |
| Rocky Linux 10 | Released |
54 kernels
|
| Rocky Linux 8 | Released |
101 kernels
|