diff --git a/NEWS b/NEWS index ced3b5c044..eecf26c511 100644 --- a/NEWS +++ b/NEWS @@ -2,6 +2,12 @@ systemd System and Service Manager CHANGES WITH 243 in spe: + * Enable unprivileged programs, neither setuid nor having file + capabilities, to send ICMP Echo requests by turning on the + net.ipv4.ping_group_range parameter of the Linux kernel for all + groups. If this is not desirable, then it can be disabled by setting + the parameter to "1 0". + * Previously, filters defined with SystemCallFilter= would have the effect that an calling an offending system call would terminate the calling thread. This behaviour never made much sense, since killing diff --git a/sysctl.d/50-default.conf b/sysctl.d/50-default.conf index 27084f6242..f0b4f610f8 100644 --- a/sysctl.d/50-default.conf +++ b/sysctl.d/50-default.conf @@ -30,6 +30,14 @@ net.ipv4.conf.all.accept_source_route = 0 # Promote secondary addresses when the primary address is removed net.ipv4.conf.all.promote_secondaries = 1 +# ping(8) without CAP_NET_ADMIN and CAP_NET_RAW +# The upper limit is set to 2^31-1. Values greater than that get rejected by +# the kernel because of this definition in linux/include/net/ping.h: +# #define GID_T_MAX (((gid_t)~0U) >> 1) +# That's not so bad because values between 2^31 and 2^32-1 are reserved on +# systemd-based systems anyway: https://systemd.io/UIDS-GIDS.html#summary +net.ipv4.ping_group_range = 0 2147483647 + # Fair Queue CoDel packet scheduler to fight bufferbloat net.core.default_qdisc = fq_codel