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| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-07-22 11:22:05 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-08-03 12:03:52 +0200 |
| commit | 4685f16b3a5d16bc515524eeb0ed8b692a929854 (patch) | |
| tree | e6104b9dd2abbf36410004acaa76ac395900ce47 | |
| parent | eaccca7a0bb8770d2683e817ae6d72dad2b3d5d5 (diff) | |
| download | linux-stable-4685f16b3a5d16bc515524eeb0ed8b692a929854.tar.gz linux-stable-4685f16b3a5d16bc515524eeb0ed8b692a929854.tar.bz2 linux-stable-4685f16b3a5d16bc515524eeb0ed8b692a929854.zip | |
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 a9cd9c2bd84e..19c6e7b93d3d 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -1037,6 +1037,7 @@ 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; @@ -1058,14 +1059,16 @@ 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); |