Current Dir: /snap/core22/2437/etc/sysctl.d/ [FILE] 10-console-messages.conf [ edit | delete | rename ] [FILE] 10-ipv6-privacy.conf [ edit | delete | rename ] [FILE] 10-kernel-hardening.conf [ edit | delete | rename ] [FILE] 10-magic-sysrq.conf [ edit | delete | rename ] [FILE] 10-network-security.conf [ edit | delete | rename ] [FILE] 10-ptrace.conf [ edit | delete | rename ] [FILE] 10-zeropage.conf [ edit | delete | rename ] [FILE] README.sysctl [ edit | delete | rename ] Viewing: /snap/core22/2437/etc/sysctl.d/10-kernel-hardening.conf # These settings are specific to hardening the kernel itself from attack # from userspace, rather than protecting userspace from other malicious # userspace things. # # # When an attacker is trying to exploit the local kernel, it is often # helpful to be able to examine where in memory the kernel, modules, # and data structures live. As such, kernel addresses should be treated # as sensitive information. # # Many files and interfaces contain these addresses (e.g. /proc/kallsyms, # /proc/modules, etc), and this setting can censor the addresses. A value # of "0" allows all users to see the kernel addresses. A value of "1" # limits visibility to the root user, and "2" blocks even the root user. kernel.kptr_restrict = 1 # Access to the kernel log buffer can be especially useful for an attacker # attempting to exploit the local kernel, as kernel addresses and detailed # call traces are frequently found in kernel oops messages. Setting # dmesg_restrict to "0" allows all users to view the kernel log buffer, # and setting it to "1" restricts access to those with CAP_SYSLOG. # # dmesg_restrict defaults to 1 via CONFIG_SECURITY_DMESG_RESTRICT, only # uncomment the following line to disable. # kernel.dmesg_restrict = 0