[PATCH net-next 6/8] ipv6: annotate data-races around sysctl.ip6_rt_gc_interval
From: Eric Dumazet <edumazet@google.com>
Date: 2026-01-15 09:41:55
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
Add READ_ONCE() on lockless reads of net->ipv6.sysctl.ip6_rt_gc_interval Signed-off-by: Eric Dumazet <edumazet@google.com> --- net/ipv6/ip6_fib.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 2111af022d946d0b9e1a35abdcbac39cbe00f921..174d38c70ac454ac4bd2399a4567862e887150e3 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c@@ -1374,14 +1374,14 @@ static void fib6_start_gc(struct net *net, struct fib6_info *rt) if (!timer_pending(&net->ipv6.ip6_fib_timer) && (rt->fib6_flags & RTF_EXPIRES)) mod_timer(&net->ipv6.ip6_fib_timer, - jiffies + net->ipv6.sysctl.ip6_rt_gc_interval); + jiffies + READ_ONCE(net->ipv6.sysctl.ip6_rt_gc_interval)); } void fib6_force_start_gc(struct net *net) { if (!timer_pending(&net->ipv6.ip6_fib_timer)) mod_timer(&net->ipv6.ip6_fib_timer, - jiffies + net->ipv6.sysctl.ip6_rt_gc_interval); + jiffies + READ_ONCE(net->ipv6.sysctl.ip6_rt_gc_interval)); } static void __fib6_update_sernum_upto_root(struct fib6_info *rt,
@@ -2413,6 +2413,7 @@ static void fib6_gc_all(struct net *net, struct fib6_gc_args *gc_args) void fib6_run_gc(unsigned long expires, struct net *net, bool force) { struct fib6_gc_args gc_args; + int ip6_rt_gc_interval; unsigned long now; if (force) {
@@ -2421,8 +2422,8 @@ void fib6_run_gc(unsigned long expires, struct net *net, bool force) mod_timer(&net->ipv6.ip6_fib_timer, jiffies + HZ); return; } - gc_args.timeout = expires ? (int)expires : - net->ipv6.sysctl.ip6_rt_gc_interval; + ip6_rt_gc_interval = READ_ONCE(net->ipv6.sysctl.ip6_rt_gc_interval); + gc_args.timeout = expires ? (int)expires : ip6_rt_gc_interval; gc_args.more = 0; fib6_gc_all(net, &gc_args);
@@ -2431,8 +2432,7 @@ void fib6_run_gc(unsigned long expires, struct net *net, bool force) if (gc_args.more) mod_timer(&net->ipv6.ip6_fib_timer, - round_jiffies(now - + net->ipv6.sysctl.ip6_rt_gc_interval)); + round_jiffies(now + ip6_rt_gc_interval)); else timer_delete(&net->ipv6.ip6_fib_timer); spin_unlock_bh(&net->ipv6.fib6_gc_lock);
--
2.52.0.457.g6b5491de43-goog