CVE-2021-47298
kernel: bpf, sockmap: Fix potential memory leak on unlikely error case
Severity
LowRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · May 21, 2024
Updated · November 21, 2025
Description
In the Linux kernel, the following vulnerability has been resolved:
bpf, sockmap: Fix potential memory leak on unlikely error case
If skb_linearize is needed and fails we could leak a msg on the error handling. To fix ensure we kfree the msg block before returning error. Found during code review.
Statement
The default Red Hat Enterprise Linux kernel prevents unprivileged users from being able to use eBPF by the kernel.unprivileged_bpf_disabled sysctl. This would require a privileged user with CAP_SYS_ADMIN or root to be able to abuse this flaw reducing its attack space.
For the Red Hat Enterprise Linux 9 to confirm the current state, inspect the sysctl with the command:
cat /proc/sys/kernel/unprivileged_bpf_disabled
The setting of 1 would mean that unprivileged users can not use eBPF, mitigating the flaw.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 4.4CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L
CWE-401 · Missing Release of Memory after Effective Lifetime