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dkim=pass header.d=link38.eu header.s=201803 header.b=5LwbOws4; dmarc=pass (policy=none) header.from=link38.eu; spf=pass (mail01.ipfire.org: domain of peter.mueller@link38.eu designates 2a03:4000:6:432c:1f9e:48:ac3:199 as permitted sender) smtp.mailfrom=peter.mueller@link38.eu X-Spamd-Result: default: False [-10.63 / 11.00]; ARC_NA(0.00)[]; R_DKIM_ALLOW(-0.20)[link38.eu:s=201803]; BAYES_HAM(-3.00)[100.00%]; FROM_HAS_DN(0.00)[]; R_SPF_ALLOW(-0.20)[+ip6:2a03:4000:6:432c:1f9e:48:ac3:199]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; RCPT_COUNT_ONE(0.00)[1]; TO_DN_ALL(0.00)[]; DKIM_TRACE(0.00)[link38.eu:+]; DMARC_POLICY_ALLOW(-0.50)[link38.eu,none]; MX_GOOD(-0.01)[cached: mx-nbg.link38.eu]; NEURAL_HAM(-2.83)[-0.944,0]; RCVD_COUNT_ZERO(0.00)[0]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; IP_SCORE(-3.78)[ip: (-9.91), ipnet: 2a03:4000::/32(-4.95), asn: 197540(-3.96), country: DE(-0.09)]; ASN(0.00)[asn:197540, ipnet:2a03:4000::/32, country:DE]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_ALL(0.00)[] X-Spam-Status: No, score=-10.63 X-Rspamd-Server: mail01.i.ipfire.org X-BeenThere: development@lists.ipfire.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: IPFire development talk List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: development-bounces@lists.ipfire.org Sender: "Development" In order to make local privilege escalation more harder, hide kernel addresses in various /proc files against users with root (or similar) permissions, too. Common system hardening tools such as lynis recommend this. Signed-off-by: Peter Müller --- setup/sysctl/kernel-hardening.conf | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/setup/sysctl/kernel-hardening.conf b/setup/sysctl/kernel-hardening.conf index 6751bbef6..9bb6e9f45 100644 --- a/setup/sysctl/kernel-hardening.conf +++ b/setup/sysctl/kernel-hardening.conf @@ -1,5 +1,5 @@ # Try to keep kernel address exposures out of various /proc files (kallsyms, modules, etc). -kernel.kptr_restrict = 1 +kernel.kptr_restrict = 2 # Avoid kernel memory address exposures via dmesg. kernel.dmesg_restrict = 1