| Message ID | 20201107193515.1469030-2-vincent@bernat.ch |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net-next,v2,1/3] net: evaluate net.ipvX.conf.all.ignore_routes_with_linkdown | expand |
| Context | Check | Description |
|---|---|---|
| jkicinski/cover_letter | warning | Series does not have a cover letter |
| jkicinski/fixes_present | success | Link |
| jkicinski/patch_count | success | Link |
| jkicinski/tree_selection | success | Clearly marked for net-next |
| jkicinski/subject_prefix | success | Link |
| jkicinski/source_inline | success | Was 0 now: 0 |
| jkicinski/verify_signedoff | success | Link |
| jkicinski/module_param | success | Was 0 now: 0 |
| jkicinski/build_32bit | success | Errors and warnings before: 642 this patch: 642 |
| jkicinski/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| jkicinski/verify_fixes | success | Link |
| jkicinski/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 17 lines checked |
| jkicinski/build_allmodconfig_warn | success | Errors and warnings before: 729 this patch: 729 |
| jkicinski/header_inline | success | Link |
| jkicinski/stable | success | Stable not CCed |
diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index 2aaf40b2d2cd..dd2b12a32b73 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -1554,6 +1554,9 @@ igmpv3_unsolicited_report_interval - INTEGER Default: 1000 (1 seconds) +ignore_routes_with_linkdown - BOOLEAN + Ignore routes whose link is down when performing a FIB lookup. + promote_secondaries - BOOLEAN When a primary IP address is removed from this interface promote a corresponding secondary IP address instead of diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h index 3515ca64e638..3bbcddd22df8 100644 --- a/include/linux/inetdevice.h +++ b/include/linux/inetdevice.h @@ -126,7 +126,7 @@ static inline void ipv4_devconf_setall(struct in_device *in_dev) IN_DEV_ORCONF((in_dev), ACCEPT_REDIRECTS))) #define IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) \ - IN_DEV_CONF_GET((in_dev), IGNORE_ROUTES_WITH_LINKDOWN) + IN_DEV_ORCONF((in_dev), IGNORE_ROUTES_WITH_LINKDOWN) #define IN_DEV_ARPFILTER(in_dev) IN_DEV_ORCONF((in_dev), ARPFILTER) #define IN_DEV_ARP_ACCEPT(in_dev) IN_DEV_ORCONF((in_dev), ARP_ACCEPT)
Introduced in 0eeb075fad73, the "ignore_routes_with_linkdown" sysctl ignores a route whose interface is down. It is provided as a per-interface sysctl. However, while a "all" variant is exposed, it was a noop since it was never evaluated. We use the usual "or" logic for this kind of sysctls. Tested with: ip link add type veth # veth0 + veth1 ip link add type veth # veth1 + veth2 ip link set up dev veth0 ip link set up dev veth1 # link-status paired with veth0 ip link set up dev veth2 ip link set up dev veth3 # link-status paired with veth2 # First available path ip -4 addr add 203.0.113.${uts#H}/24 dev veth0 ip -6 addr add 2001:db8:1::${uts#H}/64 dev veth0 # Second available path ip -4 addr add 192.0.2.${uts#H}/24 dev veth2 ip -6 addr add 2001:db8:2::${uts#H}/64 dev veth2 # More specific route through first path ip -4 route add 198.51.100.0/25 via 203.0.113.254 # via veth0 ip -6 route add 2001:db8:3::/56 via 2001:db8:1::ff # via veth0 # Less specific route through second path ip -4 route add 198.51.100.0/24 via 192.0.2.254 # via veth2 ip -6 route add 2001:db8:3::/48 via 2001:db8:2::ff # via veth2 # H1: enable on "all" # H2: enable on "veth0" for v in ipv4 ipv6; do case $uts in H1) sysctl -qw net.${v}.conf.all.ignore_routes_with_linkdown=1 ;; H2) sysctl -qw net.${v}.conf.veth0.ignore_routes_with_linkdown=1 ;; esac done set -xe # When veth0 is up, best route is through veth0 ip -o route get 198.51.100.1 | grep -Fw veth0 ip -o route get 2001:db8:3::1 | grep -Fw veth0 # When veth0 is down, best route should be through veth2 on H1/H2, # but on veth0 on H2 ip link set down dev veth1 # down veth0 ip route show [ $uts != H3 ] || ip -o route get 198.51.100.1 | grep -Fw veth0 [ $uts != H3 ] || ip -o route get 2001:db8:3::1 | grep -Fw veth0 [ $uts = H3 ] || ip -o route get 198.51.100.1 | grep -Fw veth2 [ $uts = H3 ] || ip -o route get 2001:db8:3::1 | grep -Fw veth2 Without this patch, the two last lines would fail on H1 (the one using the "all" sysctl). With the patch, everything succeeds as expected. Also document the sysctl in `ip-sysctl.rst`. Fixes: 0eeb075fad73 ("net: ipv4 sysctl option to ignore routes when nexthop link is down") Signed-off-by: Vincent Bernat <vincent@bernat.ch> --- Documentation/networking/ip-sysctl.rst | 3 +++ include/linux/inetdevice.h | 2 +- 2 files changed, 4 insertions(+), 1 deletion(-)