# \[PATCH 05/10\] net: turn sk\_peer\_pid into an array indexed by pid type - From: Christian Brauner \ - Date: 2026-08-31 11:21:45 - List: netdev - Page: https://ratatoskr.run/netdev/2026/08/17483576 - Thread: https://ratatoskr.run/netdev/2026/08/17483571/t.md ```text 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) --- 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 ```