Am Mo., 31. Aug. 2026 um 13:21 Uhr schrieb Christian Brauner
[off-list ref]:
Currently only the struct pid of the thread-group leader is recorded.
The identity of the actual thread that connected to a given socket
cannot be retrieved.
Add the plumbing to make it possible to retrieve a pidfd for the
connecting thread. Nothing uses the thread-specific struct pid yet. No
functional changes.
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
LGTM
Reviewed-by: Alexander Mikhalitsyn <redacted>
quoted hunk ↗ jump to hunk
---
net/unix/af_unix.c | 30 +++++++++++++-----------------
1 file changed, 13 insertions(+), 17 deletions(-)
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 335abd23c9bf..d01ee76c8026 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -743,51 +743,47 @@ struct unix_peercred {
static inline int prepare_peercred(struct unix_peercred *peercred)
{
- struct pid *pid;
int err;
- pid = task_tgid(current);
- err = pidfs_register_pid(pid);
- if (likely(!err)) {
- peercred->peer_pid[PIDTYPE_TGID] = get_pid(pid);
- peercred->peer_cred = get_current_cred();
+ get_task_pids(peercred->peer_pid, current);
+ err = pidfs_register_pids(peercred->peer_pid);
+ if (unlikely(err)) {
+ put_pids(peercred->peer_pid);
+ return err;
}
- return err;
+
+ peercred->peer_cred = get_current_cred();
+ return 0;
}
static void drop_peercred(struct unix_peercred *peercred)
{
const struct cred *cred = NULL;
- struct pid *pid = NULL;
might_sleep();
- swap(peercred->peer_pid[PIDTYPE_TGID], pid);
+ put_pids(peercred->peer_pid);
swap(peercred->peer_cred, cred);
-
- put_pid(pid);
put_cred(cred);
}
static inline void init_peercred(struct sock *sk,
const struct unix_peercred *peercred)
{
- sk->sk_peer_pid[PIDTYPE_TGID] = peercred->peer_pid[PIDTYPE_TGID];
+ memcpy(sk->sk_peer_pid, peercred->peer_pid, sizeof(sk->sk_peer_pid));
sk->sk_peer_cred = peercred->peer_cred;
}
static void update_peercred(struct sock *sk, struct unix_peercred *peercred)
{
const struct cred *old_cred;
- struct pid *old_pid;
spin_lock(&sk->sk_peer_lock);
- old_pid = sk->sk_peer_pid[PIDTYPE_TGID];
+ swap_pids(sk->sk_peer_pid, peercred->peer_pid);
old_cred = sk->sk_peer_cred;
- init_peercred(sk, peercred);
+ sk->sk_peer_cred = peercred->peer_cred;
spin_unlock(&sk->sk_peer_lock);
- peercred->peer_pid[PIDTYPE_TGID] = old_pid;
peercred->peer_cred = old_cred;
}
@@ -796,7 +792,7 @@ 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[PIDTYPE_TGID] = get_pid(peersk->sk_peer_pid[PIDTYPE_TGID]);
+ get_pids(sk->sk_peer_pid, peersk->sk_peer_pid);
sk->sk_peer_cred = get_cred(peersk->sk_peer_cred);
spin_unlock(&sk->sk_peer_lock);
}
--2.53.0