Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
netfilter: xt_owner: no longer acquire sk_callback_lock in mt_owner()
After commit 983512f3a87f ("net: Drop the lock in skb_may_tx_timestamp()")
from Sebastian Andrzej Siewior, apply the same logic in mt_owner()
to avoid touching sk_callback_lock.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
authored by
Eric Dumazet
and committed by
Florian Westphal
cdec942a
5663ac3e
+14
-14
+14
-14
net/netfilter/xt_owner.c
+14
-14
net/netfilter/xt_owner.c
···
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owner_mt(const struct sk_buff *skb, struct xt_action_param *par)
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{
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const struct xt_owner_match_info *info = par->matchinfo;
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-
const struct file *filp;
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struct sock *sk = skb_to_full_sk(skb);
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struct net *net = xt_net(par);
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+
const struct socket *sock;
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const struct file *filp;
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if (!sk || !sk->sk_socket || !net_eq(net, sock_net(sk)))
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if (!sk || !READ_ONCE(sk->sk_socket) || !net_eq(net, sock_net(sk)))
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return (info->match ^ info->invert) == 0;
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else if (info->match & info->invert & XT_OWNER_SOCKET)
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/*
···
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*/
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return false;
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-
read_lock_bh(&sk->sk_callback_lock);
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filp = sk->sk_socket ? sk->sk_socket->file : NULL;
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if (filp == NULL) {
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read_unlock_bh(&sk->sk_callback_lock);
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/* The sk pointer remains valid as long as the skb is. The sk_socket and
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* file pointer may become NULL if the socket is closed. Both structures
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* (including file->cred) are RCU freed which means they can be accessed
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* within a RCU read section.
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*/
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sock = READ_ONCE(sk->sk_socket);
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filp = sock ? READ_ONCE(sock->file) : NULL;
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if (filp == NULL)
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return ((info->match ^ info->invert) &
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(XT_OWNER_UID | XT_OWNER_GID)) == 0;
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-
}
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if (info->match & XT_OWNER_UID) {
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kuid_t uid_min = make_kuid(net->user_ns, info->uid_min);
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kuid_t uid_max = make_kuid(net->user_ns, info->uid_max);
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+
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if ((uid_gte(filp->f_cred->fsuid, uid_min) &&
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uid_lte(filp->f_cred->fsuid, uid_max)) ^
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!(info->invert & XT_OWNER_UID)) {
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read_unlock_bh(&sk->sk_callback_lock);
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!(info->invert & XT_OWNER_UID))
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return false;
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-
}
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}
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if (info->match & XT_OWNER_GID) {
···
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}
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}
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-
if (match ^ !(info->invert & XT_OWNER_GID)) {
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read_unlock_bh(&sk->sk_callback_lock);
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if (match ^ !(info->invert & XT_OWNER_GID))
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return false;
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-
}
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}
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-
read_unlock_bh(&sk->sk_callback_lock);
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return true;
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}
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