diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-07-22 11:22:05 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-08-03 12:05:26 +0200 |
| commit | 743f9002f8cada8a89f1cef26bbe7b5bf697070a (patch) | |
| tree | 60e8df0ff1be457809eb7fde0672b20f83d55aa7 | |
| parent | 72e2655099319adbd67ff0bdffae7e5adfcb204f (diff) | |
ipv4: Fix data-races around sysctl_fib_notify_on_flag_change.
[ Upstream commit 96b9bd8c6d125490f9adfb57d387ef81a55a103e ]
While reading sysctl_fib_notify_on_flag_change, it can be changed
concurrently. Thus, we need to add READ_ONCE() to its readers.
Fixes: 680aea08e78c ("net: ipv4: Emit notification when fib hardware flags are changed")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/ipv4/fib_trie.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c index 43a496272227..c1b53854047b 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -1042,6 +1042,7 @@ fib_find_matching_alias(struct net *net, const struct fib_rt_info *fri) void fib_alias_hw_flags_set(struct net *net, const struct fib_rt_info *fri) { + u8 fib_notify_on_flag_change; struct fib_alias *fa_match; struct sk_buff *skb; int err; @@ -1063,14 +1064,16 @@ void fib_alias_hw_flags_set(struct net *net, const struct fib_rt_info *fri) WRITE_ONCE(fa_match->offload, fri->offload); WRITE_ONCE(fa_match->trap, fri->trap); + fib_notify_on_flag_change = READ_ONCE(net->ipv4.sysctl_fib_notify_on_flag_change); + /* 2 means send notifications only if offload_failed was changed. */ - if (net->ipv4.sysctl_fib_notify_on_flag_change == 2 && + if (fib_notify_on_flag_change == 2 && READ_ONCE(fa_match->offload_failed) == fri->offload_failed) goto out; WRITE_ONCE(fa_match->offload_failed, fri->offload_failed); - if (!net->ipv4.sysctl_fib_notify_on_flag_change) + if (!fib_notify_on_flag_change) goto out; skb = nlmsg_new(fib_nlmsg_size(fa_match->fa_info), GFP_ATOMIC); |