From: Christian Brauner <brauner@kernel.org>
To: Jakub Kicinski <kuba@kernel.org>,
Kuniyuki Iwashima <kuniyu@google.com>,
Oleg Nesterov <oleg@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>,
Eric Dumazet <edumazet@google.com>,
Paolo Abeni <pabeni@redhat.com>, Simon Horman <horms@kernel.org>,
Willem de Bruijn <willemb@google.com>,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
Alexander Viro <viro@zeniv.linux.org.uk>,
Jan Kara <jack@suse.cz>,
linux-fsdevel@vger.kernel.org,
Alexander Mikhalitsyn <alexander@mihalicyn.com>,
"Christian Brauner (Amutable)" <brauner@kernel.org>
Subject: [PATCH 05/10] net: turn sk_peer_pid into an array indexed by pid type
Date: Mon, 31 Aug 2026 13:21:17 +0200 [thread overview]
Message-ID: <20260831-work-unix-passpidfd-v1-5-70cbfda0c7ba@kernel.org> (raw)
In-Reply-To: <20260831-work-unix-passpidfd-v1-0-70cbfda0c7ba@kernel.org>
Currently only the struct pid of the thread-group leader is recorded
for a socket's peer. To make room for the struct pid of the thread that
called connect(), listen() or socketpair() turn sk_peer_pid into an
array indexed by pid type. All users, including bluetooth and the
coredump socket, keep using the PIDTYPE_TGID slot.
Nothing fills the PIDTYPE_PID slot yet. No functional changes.
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
---
fs/coredump.c | 2 +-
include/net/sock.h | 4 ++--
net/bluetooth/af_bluetooth.c | 6 +++---
net/bluetooth/hci_sock.c | 8 ++++----
net/bluetooth/l2cap_sock.c | 2 +-
net/core/sock.c | 9 +++++----
net/unix/af_unix.c | 14 +++++++-------
7 files changed, 23 insertions(+), 22 deletions(-)
diff --git a/fs/coredump.c b/fs/coredump.c
index ac3cd74808c6..71a0093ada1b 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -722,7 +722,7 @@ static bool coredump_sock_connect(struct core_name *cn, struct coredump_params *
}
/* ... and validate that @sk_peer_pid matches @cprm.pid. */
- if (WARN_ON_ONCE(unix_peer(socket->sk)->sk_peer_pid != cprm->pid))
+ if (WARN_ON_ONCE(unix_peer(socket->sk)->sk_peer_pid[PIDTYPE_TGID] != cprm->pid))
return false;
cprm->limit = RLIM_INFINITY;
diff --git a/include/net/sock.h b/include/net/sock.h
index fc09c92e8a83..67b743bab220 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -301,7 +301,7 @@ struct sk_filter;
* @sk_type: socket type (%SOCK_STREAM, etc)
* @sk_protocol: which protocol this socket belongs in this network family
* @sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred
- * @sk_peer_pid: &struct pid for this socket's peer
+ * @sk_peer_pid: &struct pid for this socket's peer, by pid type
* @sk_peer_cred: %SO_PEERCRED setting
* @sk_rcvlowat: %SO_RCVLOWAT setting
* @sk_rcvtimeo: %SO_RCVTIMEO setting
@@ -546,7 +546,7 @@ struct sock {
u64 sk_ino;
spinlock_t sk_peer_lock;
int sk_bind_phc;
- struct pid *sk_peer_pid;
+ DECLARE_PIDS(sk_peer_pid, PIDTYPE_TGID);
const struct cred *sk_peer_cred;
ktime_t sk_stamp;
diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
index 411d66f24393..7758e9ea3848 100644
--- a/net/bluetooth/af_bluetooth.c
+++ b/net/bluetooth/af_bluetooth.c
@@ -161,7 +161,7 @@ struct sock *bt_sock_alloc(struct net *net, struct socket *sock,
/* Init peer information so it can be properly monitored */
if (!kern) {
spin_lock(&sk->sk_peer_lock);
- sk->sk_peer_pid = get_pid(task_tgid(current));
+ sk->sk_peer_pid[PIDTYPE_TGID] = get_pid(task_tgid(current));
sk->sk_peer_cred = get_current_cred();
spin_unlock(&sk->sk_peer_lock);
}
@@ -235,9 +235,9 @@ void bt_accept_enqueue(struct sock *parent, struct sock *sk, bool bh)
* socket is allocated by the kernel.
*/
spin_lock(&sk->sk_peer_lock);
- old_pid = sk->sk_peer_pid;
+ old_pid = sk->sk_peer_pid[PIDTYPE_TGID];
old_cred = sk->sk_peer_cred;
- sk->sk_peer_pid = get_pid(parent->sk_peer_pid);
+ sk->sk_peer_pid[PIDTYPE_TGID] = get_pid(parent->sk_peer_pid[PIDTYPE_TGID]);
sk->sk_peer_cred = get_cred(parent->sk_peer_cred);
spin_unlock(&sk->sk_peer_lock);
diff --git a/net/bluetooth/hci_sock.c b/net/bluetooth/hci_sock.c
index 070ca388f9ac..91e4738eabdb 100644
--- a/net/bluetooth/hci_sock.c
+++ b/net/bluetooth/hci_sock.c
@@ -273,21 +273,21 @@ static void hci_sock_copy_creds(struct sock *sk, struct sk_buff *skb)
creds = &bt_cb(skb)->creds;
/* Check if peer credentials is set */
- if (!sk->sk_peer_pid) {
+ if (!sk->sk_peer_pid[PIDTYPE_TGID]) {
/* Check if parent peer credentials is set */
- if (bt_sk(sk)->parent && bt_sk(sk)->parent->sk_peer_pid)
+ if (bt_sk(sk)->parent && bt_sk(sk)->parent->sk_peer_pid[PIDTYPE_TGID])
sk = bt_sk(sk)->parent;
else
return;
}
/* Check if scm_creds already set */
- if (creds->pid == pid_vnr(sk->sk_peer_pid))
+ if (creds->pid == pid_vnr(sk->sk_peer_pid[PIDTYPE_TGID]))
return;
memset(creds, 0, sizeof(*creds));
- creds->pid = pid_vnr(sk->sk_peer_pid);
+ creds->pid = pid_vnr(sk->sk_peer_pid[PIDTYPE_TGID]);
if (sk->sk_peer_cred) {
creds->uid = sk->sk_peer_cred->uid;
creds->gid = sk->sk_peer_cred->gid;
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index 1194c37e466f..872d8fb31b6f 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -1890,7 +1890,7 @@ static struct pid *l2cap_sock_get_peer_pid_cb(struct l2cap_chan *chan)
{
struct sock *sk = chan->data;
- return sk->sk_peer_pid;
+ return sk->sk_peer_pid[PIDTYPE_TGID];
}
static void l2cap_sock_suspend_cb(struct l2cap_chan *chan)
diff --git a/net/core/sock.c b/net/core/sock.c
index f9615b0de10e..6ada7e7eb7d7 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1928,7 +1928,8 @@ int sk_getsockopt(struct sock *sk, int level, int optname,
len = sizeof(peercred);
spin_lock(&sk->sk_peer_lock);
- cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
+ cred_to_ucred(sk->sk_peer_pid[PIDTYPE_TGID], sk->sk_peer_cred,
+ &peercred);
spin_unlock(&sk->sk_peer_lock);
if (copy_to_sockptr(optval, &peercred, len))
@@ -1947,7 +1948,7 @@ int sk_getsockopt(struct sock *sk, int level, int optname,
len = sizeof(pidfd);
spin_lock(&sk->sk_peer_lock);
- peer_pid = get_pid(sk->sk_peer_pid);
+ peer_pid = get_pid(sk->sk_peer_pid[PIDTYPE_TGID]);
spin_unlock(&sk->sk_peer_lock);
if (!peer_pid)
@@ -2401,7 +2402,7 @@ static void __sk_destruct(struct rcu_head *head)
/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
put_cred(sk->sk_peer_cred);
- put_pid(sk->sk_peer_pid);
+ put_pids(sk->sk_peer_pid);
if (likely(sk->sk_net_refcnt)) {
put_net_track(net, &sk->ns_tracker);
@@ -3797,7 +3798,7 @@ void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
sk->sk_frag.offset = 0;
sk->sk_peek_off = -1;
- sk->sk_peer_pid = NULL;
+ memset(sk->sk_peer_pid, 0, sizeof(sk->sk_peer_pid));
sk->sk_peer_cred = NULL;
spin_lock_init(&sk->sk_peer_lock);
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 468a9c479b87..335abd23c9bf 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -737,7 +737,7 @@ static void unix_release_sock(struct sock *sk, int embrion)
}
struct unix_peercred {
- struct pid *peer_pid;
+ DECLARE_PIDS(peer_pid, PIDTYPE_TGID);
const struct cred *peer_cred;
};
@@ -749,7 +749,7 @@ static inline int prepare_peercred(struct unix_peercred *peercred)
pid = task_tgid(current);
err = pidfs_register_pid(pid);
if (likely(!err)) {
- peercred->peer_pid = get_pid(pid);
+ peercred->peer_pid[PIDTYPE_TGID] = get_pid(pid);
peercred->peer_cred = get_current_cred();
}
return err;
@@ -762,7 +762,7 @@ static void drop_peercred(struct unix_peercred *peercred)
might_sleep();
- swap(peercred->peer_pid, pid);
+ swap(peercred->peer_pid[PIDTYPE_TGID], pid);
swap(peercred->peer_cred, cred);
put_pid(pid);
@@ -772,7 +772,7 @@ static void drop_peercred(struct unix_peercred *peercred)
static inline void init_peercred(struct sock *sk,
const struct unix_peercred *peercred)
{
- sk->sk_peer_pid = peercred->peer_pid;
+ sk->sk_peer_pid[PIDTYPE_TGID] = peercred->peer_pid[PIDTYPE_TGID];
sk->sk_peer_cred = peercred->peer_cred;
}
@@ -782,12 +782,12 @@ static void update_peercred(struct sock *sk, struct unix_peercred *peercred)
struct pid *old_pid;
spin_lock(&sk->sk_peer_lock);
- old_pid = sk->sk_peer_pid;
+ old_pid = sk->sk_peer_pid[PIDTYPE_TGID];
old_cred = sk->sk_peer_cred;
init_peercred(sk, peercred);
spin_unlock(&sk->sk_peer_lock);
- peercred->peer_pid = old_pid;
+ peercred->peer_pid[PIDTYPE_TGID] = old_pid;
peercred->peer_cred = old_cred;
}
@@ -796,7 +796,7 @@ static void copy_peercred(struct sock *sk, struct sock *peersk)
lockdep_assert_held(&unix_sk(peersk)->lock);
spin_lock(&sk->sk_peer_lock);
- sk->sk_peer_pid = get_pid(peersk->sk_peer_pid);
+ sk->sk_peer_pid[PIDTYPE_TGID] = get_pid(peersk->sk_peer_pid[PIDTYPE_TGID]);
sk->sk_peer_cred = get_cred(peersk->sk_peer_cred);
spin_unlock(&sk->sk_peer_lock);
}
--
2.53.0
next prev parent reply other threads:[~2026-08-31 11:21 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-31 11:21 [PATCH 00/10] net: support thread-specific pidfds for send and connect Christian Brauner
2026-08-31 11:21 ` [PATCH 01/10] pid: add helpers to operate on a struct pid array Christian Brauner
2026-08-31 11:21 ` [PATCH 02/10] af_unix: record the pid of the sending thread Christian Brauner
2026-08-31 11:21 ` [PATCH 03/10] net: add SO_PASSPIDFD_THREAD to get a thread-specific SCM_PIDFD Christian Brauner
2026-08-31 11:21 ` [PATCH 04/10] selftests/net: SO_PASSPIDFD_THREAD Christian Brauner
2026-08-31 11:21 ` Christian Brauner [this message]
2026-09-02 0:20 ` [PATCH 05/10] net: turn sk_peer_pid into an array indexed by pid type Jakub Kicinski
2026-08-31 11:21 ` [PATCH 06/10] af_unix: record the pid of the connecting thread Christian Brauner
2026-08-31 11:21 ` [PATCH 07/10] net: add SO_PEERPIDFD_THREAD to get a thread-specific pidfd Christian Brauner
2026-08-31 11:21 ` [PATCH 08/10] selftests/net: SO_PEERPIDFD_THREAD Christian Brauner
2026-08-31 11:21 ` [PATCH 09/10] pidfs: record the coredump on the dumping thread's pid too Christian Brauner
2026-08-31 11:21 ` [PATCH 10/10] selftests/coredump: check the dumping thread's pidfd Christian Brauner
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