| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <3f38fb1c0c5544de4cea8bb13e0adcbba17bebd3.1409665378.git.hannes@stressinduktion.org>
Date: Tue, 2 Sep 2014 15:49:25 +0200
From: Hannes Frederic Sowa <hannes@...essinduktion.org>
To: netdev@...r.kernel.org
Cc: Flavio Leitner <fbl@...hat.com>
Subject: [PATCH net-next v3 1/2] ipv6: add sysctl_mld_qrv to configure query robustness variable
This patch adds a new sysctl_mld_qrv knob to configure the mldv1/v2 query
robustness variable. It specifies how many retransmit of unsolicited mld
retransmit should happen. Admins might want to tune this on lossy links.
Also reset mld state on interface down/up, so we pick up new sysctl
settings during interface up event.
IPv6 certification requests this knob to be available.
I didn't make this knob netns specific, as it is mostly a setting in a
physical environment and should be per host.
Cc: Flavio Leitner <fbl@...hat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@...essinduktion.org>
---
v2) no changes to original version
v3) - enhance Documentation/networking/ip-sysctl.txt with sysctl limits
- fix clamping of remotely received mld_qrv value
Documentation/networking/ip-sysctl.txt | 5 +++++
include/net/ipv6.h | 1 +
net/ipv6/mcast.c | 25 +++++++++++++++----------
net/ipv6/sysctl_net_ipv6.c | 10 ++++++++++
4 files changed, 31 insertions(+), 10 deletions(-)
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index 3cce8ea..cfc71ac 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -1152,6 +1152,11 @@ anycast_src_echo_reply - BOOLEAN
FALSE: disabled
Default: FALSE
+mld_qrv - INTEGER
+ Controls the MLD query robustness variable (see RFC3810 9.1).
+ Default: 2 (as specified by RFC3810 9.1)
+ Minimum: 1 (as specified by RFC6636 4.5)
+
IPv6 Fragmentation:
ip6frag_high_thresh - INTEGER
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index a2db816..7e247e9 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -121,6 +121,7 @@ struct frag_hdr {
/* sysctls */
extern int sysctl_mld_max_msf;
+extern int sysctl_mld_qrv;
#define _DEVINC(net, statname, modifier, idev, field) \
({ \
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 7088179..6491942 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -121,6 +121,7 @@ static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
#define IPV6_MLD_MAX_MSF 64
int sysctl_mld_max_msf __read_mostly = IPV6_MLD_MAX_MSF;
+int sysctl_mld_qrv __read_mostly = MLD_QRV_DEFAULT;
/*
* socket join on multicast group
@@ -1191,15 +1192,16 @@ static void mld_update_qrv(struct inet6_dev *idev,
* and SHOULD NOT be one. Catch this here if we ever run
* into such a case in future.
*/
+ const int min_qrv = min(MLD_QRV_DEFAULT, sysctl_mld_qrv);
WARN_ON(idev->mc_qrv == 0);
if (mlh2->mld2q_qrv > 0)
idev->mc_qrv = mlh2->mld2q_qrv;
- if (unlikely(idev->mc_qrv < 2)) {
+ if (unlikely(idev->mc_qrv < min_qrv)) {
net_warn_ratelimited("IPv6: MLD: clamping QRV from %u to %u!\n",
- idev->mc_qrv, MLD_QRV_DEFAULT);
- idev->mc_qrv = MLD_QRV_DEFAULT;
+ idev->mc_qrv, min_qrv);
+ idev->mc_qrv = min_qrv;
}
}
@@ -2478,6 +2480,14 @@ void ipv6_mc_down(struct inet6_dev *idev)
mld_clear_delrec(idev);
}
+static void ipv6_mc_reset(struct inet6_dev *idev)
+{
+ idev->mc_qrv = sysctl_mld_qrv;
+ idev->mc_qi = MLD_QI_DEFAULT;
+ idev->mc_qri = MLD_QRI_DEFAULT;
+ idev->mc_v1_seen = 0;
+ idev->mc_maxdelay = unsolicited_report_interval(idev);
+}
/* Device going up */
@@ -2488,6 +2498,7 @@ void ipv6_mc_up(struct inet6_dev *idev)
/* Install multicast list, except for all-nodes (already installed) */
read_lock_bh(&idev->lock);
+ ipv6_mc_reset(idev);
for (i = idev->mc_list; i; i = i->next)
igmp6_group_added(i);
read_unlock_bh(&idev->lock);
@@ -2508,13 +2519,7 @@ void ipv6_mc_init_dev(struct inet6_dev *idev)
(unsigned long)idev);
setup_timer(&idev->mc_dad_timer, mld_dad_timer_expire,
(unsigned long)idev);
-
- idev->mc_qrv = MLD_QRV_DEFAULT;
- idev->mc_qi = MLD_QI_DEFAULT;
- idev->mc_qri = MLD_QRI_DEFAULT;
-
- idev->mc_maxdelay = unsolicited_report_interval(idev);
- idev->mc_v1_seen = 0;
+ ipv6_mc_reset(idev);
write_unlock_bh(&idev->lock);
}
diff --git a/net/ipv6/sysctl_net_ipv6.c b/net/ipv6/sysctl_net_ipv6.c
index 0c56c93..c5c10fa 100644
--- a/net/ipv6/sysctl_net_ipv6.c
+++ b/net/ipv6/sysctl_net_ipv6.c
@@ -16,6 +16,8 @@
#include <net/addrconf.h>
#include <net/inet_frag.h>
+static int one = 1;
+
static struct ctl_table ipv6_table_template[] = {
{
.procname = "bindv6only",
@@ -63,6 +65,14 @@ static struct ctl_table ipv6_rotable[] = {
.mode = 0644,
.proc_handler = proc_dointvec
},
+ {
+ .procname = "mld_qrv",
+ .data = &sysctl_mld_qrv,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &one
+ },
{ }
};
--
1.9.3
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists