diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-07-22 11:22:05 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-07-25 12:42:10 +0100 |
| commit | 96b9bd8c6d125490f9adfb57d387ef81a55a103e (patch) | |
| tree | 66d7648a2edd38f2996da441df019b0632adb5ce /net | |
| parent | 870e3a634b6a6cb1543b359007aca73fe6a03ac5 (diff) | |
| download | linux-96b9bd8c6d125490f9adfb57d387ef81a55a103e.tar.bz2 | |
ipv4: Fix data-races around sysctl_fib_notify_on_flag_change.
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>
Diffstat (limited to 'net')
| -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 46e8a5125853..452ff177e4da 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); |