diff options
| author | Eric Dumazet <edumazet@google.com> | 2025-08-28 19:58:22 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-08-29 19:36:32 -0700 |
| commit | b62a59c18b692f892dcb8109c1c2e653b2abc95c (patch) | |
| tree | 79dd62f077f3c481b682b7aaf70014c165719ed8 /net/ipv4/tcp_fastopen.c | |
| parent | tcp_metrics: use dst_dev_net_rcu() (diff) | |
| download | linux-b62a59c18b692f892dcb8109c1c2e653b2abc95c.tar.gz linux-b62a59c18b692f892dcb8109c1c2e653b2abc95c.zip | |
tcp: use dst_dev_rcu() in tcp_fastopen_active_disable_ofo_check()
Use RCU to avoid a pair of atomic operations and a potential
UAF on dst_dev()->flags.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250828195823.3958522-8-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/ipv4/tcp_fastopen.c')
| -rw-r--r-- | net/ipv4/tcp_fastopen.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c index f1884f0c9e52..7d945a527daf 100644 --- a/net/ipv4/tcp_fastopen.c +++ b/net/ipv4/tcp_fastopen.c @@ -576,11 +576,12 @@ void tcp_fastopen_active_disable_ofo_check(struct sock *sk) } } else if (tp->syn_fastopen_ch && atomic_read(&sock_net(sk)->ipv4.tfo_active_disable_times)) { - dst = sk_dst_get(sk); - dev = dst ? dst_dev(dst) : NULL; + rcu_read_lock(); + dst = __sk_dst_get(sk); + dev = dst ? dst_dev_rcu(dst) : NULL; if (!(dev && (dev->flags & IFF_LOOPBACK))) atomic_set(&sock_net(sk)->ipv4.tfo_active_disable_times, 0); - dst_release(dst); + rcu_read_unlock(); } } |