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| author | Eric Dumazet <edumazet@google.com> | 2025-08-28 19:58:22 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-11-13 15:34:17 -0500 |
| commit | bc2b881a0896c111c1041d8bb1f92a3b3873ace5 (patch) | |
| tree | 7f847a51373bdcae7f3b7e486349782dff93c038 /net | |
| parent | 047c08808c22db39ebb44fc50908089756f45ad9 (diff) | |
| download | linux-bc2b881a0896c111c1041d8bb1f92a3b3873ace5.tar.gz linux-bc2b881a0896c111c1041d8bb1f92a3b3873ace5.tar.bz2 linux-bc2b881a0896c111c1041d8bb1f92a3b3873ace5.zip | |
tcp: use dst_dev_rcu() in tcp_fastopen_active_disable_ofo_check()
[ Upstream commit b62a59c18b692f892dcb8109c1c2e653b2abc95c ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net')
| -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 86c995dc1c5e..f9460e7531ba 100644 --- a/net/ipv4/tcp_fastopen.c +++ b/net/ipv4/tcp_fastopen.c @@ -575,11 +575,12 @@ 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(); } } |