Important: kernel security and bug fix update

Topic

An update for kernel is now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es):

• kernel: use after free in eventpoll.c may lead to escalation of privilege (CVE-2020-0466)
• kernel: Use After Free in unix_gc() which could result in a local privilege escalation (CVE-2021-0920)
• kernel: xfs: raw block device data leak in XFS_IOC_ALLOCSP IOCTL (CVE-2021-4155)
• kernel: possible privileges escalation due to missing TLB flush (CVE-2022-0330)
• kernel: failing usercopy allows for use-after-free exploitation (CVE-2022-22942)
• kernel: out of bounds write in hid-multitouch.c may lead to escalation of privilege (CVE-2020-0465)
• kernel: double free in bluetooth subsystem when the HCI device initialization fails (CVE-2021-3564)
• kernel: use-after-free in function hci_sock_bound_ioctl() (CVE-2021-3573)
• kernel: possible use-after-free in bluetooth module (CVE-2021-3752)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Bug Fix(es):

• Kernel with enabled BERT does not decode CPU fatal events correctly (BZ#1950302)
• RHEL 7.9 - Call trace seen during controller random reset on IB config (BZ#1984070)
• Infinite loop in blk_set_queue_dying() from blk_queue_for_each_rl() when another CPU races and modifies the queue's blkg_list (BZ#2029574)
• NFS client kernel crash in NFS4 backchannel transmit path - ftrace_raw_event_rpc_task_queued called from rpc_run_bc_task (BZ#2039508)
• SELinux is preventing / from mount access on the filesystem /proc (BZ#2040196)

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.

Affected Products

• Red Hat Enterprise Linux Workstation 7 x86_64

Fixes

• BZ - 1920471 - CVE-2020-0465 kernel: out of bounds write in hid-multitouch.c may lead to escalation of privilege
• BZ - 1920480 - CVE-2020-0466 kernel: use after free in eventpoll.c may lead to escalation of privilege
• BZ - 1964139 - CVE-2021-3564 kernel: double free in bluetooth subsystem when the HCI device initialization fails
• BZ - 1966578 - CVE-2021-3573 kernel: use-after-free in function hci_sock_bound_ioctl()
• BZ - 1999544 - CVE-2021-3752 kernel: possible use-after-free in bluetooth module
• BZ - 2031930 - CVE-2021-0920 kernel: Use After Free in unix_gc() which could result in a local privilege escalation
• BZ - 2034813 - CVE-2021-4155 kernel: xfs: raw block device data leak in XFS_IOC_ALLOCSP IOCTL
• BZ - 2042404 - CVE-2022-0330 kernel: possible privileges escalation due to missing TLB flush
• BZ - 2044809 - CVE-2022-22942 kernel: failing usercopy allows for use-after-free exploitation

CVEs

• CVE-2020-0465
• CVE-2020-0466
• CVE-2021-0920
• CVE-2021-3564
• CVE-2021-3573
• CVE-2021-3752
• CVE-2021-4155
• CVE-2022-0330
• CVE-2022-22942

References

• https://access.redhat.com/security/updates/classification/#important