Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
netfilter: nfnetlink_queue: no longer acquire sk_callback_lock
After commit 983512f3a87f ("net: Drop the lock in skb_may_tx_timestamp()")
from Sebastian Andrzej Siewior, apply the same logic in
nfqnl_put_sk_uidgid() to avoid touching sk->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
013e2f91
b297aaef
+12
-5
+12
-5
net/netfilter/nfnetlink_queue.c
+12
-5
net/netfilter/nfnetlink_queue.c
···
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static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
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{
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+
const struct socket *sock;
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const struct file *file;
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const struct cred *cred;
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if (!sk_fullsock(sk))
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return 0;
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-
read_lock_bh(&sk->sk_callback_lock);
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-
if (sk->sk_socket && sk->sk_socket->file) {
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-
cred = sk->sk_socket->file->f_cred;
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/* The sk pointer remains valid as long as the skb is.
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* The sk_socket and file pointer may become NULL
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* if the socket is closed.
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* Both structures (including file->cred) are RCU freed
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* which means they can be accessed within a RCU read section.
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*/
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sock = READ_ONCE(sk->sk_socket);
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file = sock ? READ_ONCE(sock->file) : NULL;
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if (file) {
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cred = file->f_cred;
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if (nla_put_be32(skb, NFQA_UID,
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htonl(from_kuid_munged(&init_user_ns, cred->fsuid))))
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goto nla_put_failure;
···
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htonl(from_kgid_munged(&init_user_ns, cred->fsgid))))
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goto nla_put_failure;
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}
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read_unlock_bh(&sk->sk_callback_lock);
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return 0;
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nla_put_failure:
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read_unlock_bh(&sk->sk_callback_lock);
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return -1;
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}
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