SB2021032439 - Fedora 32 update for kernel

Description

This security bulletin contains information about 7 secuirty vulnerabilities.

1) Off-by-one (CVE-ID: CVE-2020-27171)

The vulnerability allows a local user to gain access to sensitive information.

The vulnerability exists due to an off-by-one error in kernel/bpf/verifier.c affecting out-of-bounds speculation on pointer arithmetic, leading to side-channel attacks that defeat Spectre mitigations. A local user can run a specially crafted program to gain access to sensitive information on the system.

2) Observable discrepancy (CVE-ID: CVE-2020-27170)

The vulnerability allows a local user to gain access to sensitive information.

The vulnerability exists in kernel/bpf/verifier.c due to kernel performs undesirable out-of-bounds speculation on pointer arithmetic, leading to side-channel attacks that defeat Spectre mitigations. A local user can run a specially crafted program to gain access to sensitive information.

3) Improper locking (CVE-ID: CVE-2021-28951)

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to improper locking within the io_sq_offload_start(), io_disable_sqo_submit() and io_register_enable_rings() functions in fs/io_uring.c. A local user can perform a denial of service (DoS) attack.

4) Buffer overflow (CVE-ID: CVE-2021-28952)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a boundary error in the sound/soc/qcom/sdm845.c soundwire device driver in Linux kernel. A local user can run a specially crafted program to trigger a buffer overflow, when an unexpected port ID number is encountered, and execute arbitrary code on the system with elevated privileges.

5) Buffer overflow (CVE-ID: CVE-2021-28972)

The vulnerability allows a local user to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in the drivers/pci/hotplug/rpadlpar_sysfs.c. A local administrator can trigger memory corruption and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

6) Resource exhaustion (CVE-ID: CVE-2021-28971)

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to mishandling of PEBS status in a PEBS record In intel_pmu_drain_pebs_nhm in arch/x86/events/intel/ds.c in the Linux kernel. A local user can trigger resource exhaustion and perform a denial of service (DoS) attack.

7) Race condition (CVE-ID: CVE-2021-28964)

The vulnerability allows a local user to perform a denial of service attack.

The vulnerability exists due to a race condition in the get_old_root() function in fs/btrfs/ctree.c component in the Linux kernel. A local user can exploit the race and perform a denial of service attack.

Remediation

Install update from vendor's website.

References

• https://bodhi.fedoraproject.org/updates/FEDORA-2021-25441d8137