Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
netfilter: nfnetlink_log: 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
__build_packet_message() 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
b297aaef
afc2125d
+13
-6
+13
-6
net/netfilter/nfnetlink_log.c
+13
-6
net/netfilter/nfnetlink_log.c
···
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/* UID */
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sk = skb->sk;
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if (sk && sk_fullsock(sk)) {
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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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-
struct file *file = sk->sk_socket->file;
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+
const struct socket *sock;
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+
const struct file *file;
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+
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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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const struct cred *cred = file->f_cred;
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struct user_namespace *user_ns = inst->peer_user_ns;
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__be32 uid = htonl(from_kuid_munged(user_ns, cred->fsuid));
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__be32 gid = htonl(from_kgid_munged(user_ns, cred->fsgid));
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read_unlock_bh(&sk->sk_callback_lock);
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if (nla_put_be32(inst->skb, NFULA_UID, uid) ||
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nla_put_be32(inst->skb, NFULA_GID, gid))
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goto nla_put_failure;
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-
} else
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-
read_unlock_bh(&sk->sk_callback_lock);
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+
}
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}
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/* local sequence number */