Lines Matching +full:max +full:- +full:msg
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* scm.c - Socket level control messages processing.
52 kuid_t uid = make_kuid(cred->user_ns, creds->uid);
53 kgid_t gid = make_kgid(cred->user_ns, creds->gid);
56 return -EINVAL;
58 if ((creds->pid == task_tgid_vnr(current) ||
59 ns_capable(task_active_pid_ns(current)->user_ns, CAP_SYS_ADMIN)) &&
60 ((uid_eq(uid, cred->uid) || uid_eq(uid, cred->euid) ||
61 uid_eq(uid, cred->suid)) || ns_capable(cred->user_ns, CAP_SETUID)) &&
62 ((gid_eq(gid, cred->gid) || gid_eq(gid, cred->egid) ||
63 gid_eq(gid, cred->sgid)) || ns_capable(cred->user_ns, CAP_SETGID))) {
66 return -EPERM;
76 num = (cmsg->cmsg_len - sizeof(struct cmsghdr))/sizeof(int);
82 return -EINVAL;
88 return -ENOMEM;
90 fpl->count = 0;
91 fpl->count_unix = 0;
92 fpl->max = SCM_MAX_FD;
93 fpl->user = NULL;
95 fpl->inflight = false;
96 fpl->dead = false;
97 fpl->edges = NULL;
98 INIT_LIST_HEAD(&fpl->vertices);
101 fpp = &fpl->fp[fpl->count];
103 if (fpl->count + num > fpl->max)
104 return -EINVAL;
116 return -EBADF;
120 return -EINVAL;
123 fpl->count_unix++;
126 fpl->count++;
129 if (!fpl->user)
130 fpl->user = get_uid(current_user());
137 struct scm_fp_list *fpl = scm->fp;
141 scm->fp = NULL;
142 for (i=fpl->count-1; i>=0; i--)
143 fput(fpl->fp[i]);
144 free_uid(fpl->user);
161 scm->pid = pid;
162 scm->creds.pid = pid_vnr(pid);
166 int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *p)
168 const struct proto_ops *ops = READ_ONCE(sock->ops);
172 for_each_cmsghdr(cmsg, msg) {
173 err = -EINVAL;
183 if (!CMSG_OK(msg, cmsg))
186 if (cmsg->cmsg_level != SOL_SOCKET)
189 switch (cmsg->cmsg_type)
192 if (!ops || ops->family != PF_UNIX)
194 err=scm_fp_copy(cmsg, &p->fp);
203 if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct ucred)))
210 if (!p->pid || pid_vnr(p->pid) != creds.pid) {
212 err = -ESRCH;
227 err = -EINVAL;
233 p->creds.uid = uid;
234 p->creds.gid = gid;
242 if (p->fp && !p->fp->count)
244 kfree(p->fp);
245 p->fp = NULL;
255 int put_cmsg(struct msghdr * msg, int level, int type, int len, void *data)
259 if (msg->msg_flags & MSG_CMSG_COMPAT)
260 return put_cmsg_compat(msg, level, type, len, data);
262 if (!msg->msg_control || msg->msg_controllen < sizeof(struct cmsghdr)) {
263 msg->msg_flags |= MSG_CTRUNC;
266 if (msg->msg_controllen < cmlen) {
267 msg->msg_flags |= MSG_CTRUNC;
268 cmlen = msg->msg_controllen;
271 if (msg->msg_control_is_user) {
272 struct cmsghdr __user *cm = msg->msg_control_user;
274 check_object_size(data, cmlen - sizeof(*cm), true);
281 unsafe_put_user(cmlen, &cm->cmsg_len, efault_end);
282 unsafe_put_user(level, &cm->cmsg_level, efault_end);
283 unsafe_put_user(type, &cm->cmsg_type, efault_end);
285 cmlen - sizeof(*cm), efault_end);
288 struct cmsghdr *cm = msg->msg_control;
290 cm->cmsg_level = level;
291 cm->cmsg_type = type;
292 cm->cmsg_len = cmlen;
293 memcpy(CMSG_DATA(cm), data, cmlen - sizeof(*cm));
296 cmlen = min(CMSG_SPACE(len), msg->msg_controllen);
297 if (msg->msg_control_is_user)
298 msg->msg_control_user += cmlen;
300 msg->msg_control += cmlen;
301 msg->msg_controllen -= cmlen;
307 return -EFAULT;
311 int put_cmsg_notrunc(struct msghdr *msg, int level, int type, int len,
315 if (!msg->msg_control || msg->msg_controllen < CMSG_LEN(len))
316 return -ETOOSMALL;
318 return put_cmsg(msg, level, type, len, data);
321 void put_cmsg_scm_timestamping64(struct msghdr *msg, struct scm_timestamping_internal *tss_internal)
327 tss.ts[i].tv_sec = tss_internal->ts[i].tv_sec;
328 tss.ts[i].tv_nsec = tss_internal->ts[i].tv_nsec;
331 put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPING_NEW, sizeof(tss), &tss);
335 void put_cmsg_scm_timestamping(struct msghdr *msg, struct scm_timestamping_internal *tss_internal)
341 tss.ts[i].tv_sec = tss_internal->ts[i].tv_sec;
342 tss.ts[i].tv_nsec = tss_internal->ts[i].tv_nsec;
345 put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPING_OLD, sizeof(tss), &tss);
349 static int scm_max_fds(struct msghdr *msg)
351 if (msg->msg_controllen <= sizeof(struct cmsghdr))
353 return (msg->msg_controllen - sizeof(struct cmsghdr)) / sizeof(int);
356 void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm)
359 (__force struct cmsghdr __user *)msg->msg_control_user;
360 unsigned int o_flags = (msg->msg_flags & MSG_CMSG_CLOEXEC) ? O_CLOEXEC : 0;
361 int fdmax = min_t(int, scm_max_fds(msg), scm->fp->count);
366 if (WARN_ON_ONCE(!msg->msg_control_is_user))
369 if (msg->msg_flags & MSG_CMSG_COMPAT) {
370 scm_detach_fds_compat(msg, scm);
375 err = scm_recv_one_fd(scm->fp->fp[i], cmsg_data + i, o_flags);
383 err = put_user(SOL_SOCKET, &cm->cmsg_level);
385 err = put_user(SCM_RIGHTS, &cm->cmsg_type);
387 err = put_user(cmlen, &cm->cmsg_len);
390 if (msg->msg_controllen < cmlen)
391 cmlen = msg->msg_controllen;
392 msg->msg_control_user += cmlen;
393 msg->msg_controllen -= cmlen;
397 if (i < scm->fp->count || (scm->fp->count && fdmax <= 0))
398 msg->msg_flags |= MSG_CTRUNC;
416 new_fpl = kmemdup(fpl, offsetof(struct scm_fp_list, fp[fpl->count]),
419 for (i = 0; i < fpl->count; i++)
420 get_file(fpl->fp[i]);
422 new_fpl->max = new_fpl->count;
423 new_fpl->user = get_uid(fpl->user);
425 new_fpl->inflight = false;
426 new_fpl->edges = NULL;
427 INIT_LIST_HEAD(&new_fpl->vertices);
435 static void scm_passec(struct sock *sk, struct msghdr *msg, struct scm_cookie *scm)
440 if (sk->sk_scm_security) {
441 err = security_secid_to_secctx(scm->secid, &ctx);
444 put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, ctx.len,
454 return sk->sk_scm_security;
457 static void scm_passec(struct sock *sk, struct msghdr *msg, struct scm_cookie *scm)
467 static void scm_pidfd_recv(struct msghdr *msg, struct scm_cookie *scm)
475 if (msg->msg_flags & MSG_CMSG_COMPAT)
480 if (msg->msg_controllen < len) {
481 msg->msg_flags |= MSG_CTRUNC;
485 if (!scm->pid)
488 pidfd = pidfd_prepare(scm->pid, PIDFD_STALE, &pidfd_file);
490 if (put_cmsg(msg, SOL_SOCKET, SCM_PIDFD, sizeof(int), &pidfd)) {
503 static bool __scm_recv_common(struct sock *sk, struct msghdr *msg,
506 if (!msg->msg_control) {
507 if (sk->sk_scm_credentials || sk->sk_scm_pidfd ||
508 scm->fp || scm_has_secdata(sk))
509 msg->msg_flags |= MSG_CTRUNC;
515 if (sk->sk_scm_credentials) {
518 .pid = scm->creds.pid,
519 .uid = from_kuid_munged(current_ns, scm->creds.uid),
520 .gid = from_kgid_munged(current_ns, scm->creds.gid),
523 put_cmsg(msg, SOL_SOCKET, SCM_CREDENTIALS, sizeof(ucreds), &ucreds);
526 scm_passec(sk, msg, scm);
528 if (scm->fp)
529 scm_detach_fds(msg, scm);
534 void scm_recv(struct socket *sock, struct msghdr *msg,
537 if (!__scm_recv_common(sock->sk, msg, scm, flags))
544 void scm_recv_unix(struct socket *sock, struct msghdr *msg,
547 if (!__scm_recv_common(sock->sk, msg, scm, flags))
550 if (sock->sk->sk_scm_pidfd)
551 scm_pidfd_recv(msg, scm);