summaryrefslogtreecommitdiffstats
path: root/net/unix/af_unix.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/unix/af_unix.c')
-rw-r--r--net/unix/af_unix.c441
1 files changed, 420 insertions, 21 deletions
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index ba7ced947e51..eb47b9de2380 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -113,6 +113,7 @@
#include <linux/security.h>
#include <linux/freezer.h>
#include <linux/file.h>
+#include <linux/btf_ids.h>
#include "scm.h"
@@ -494,6 +495,7 @@ static void unix_dgram_disconnected(struct sock *sk, struct sock *other)
sk_error_report(other);
}
}
+ other->sk_state = TCP_CLOSE;
}
static void unix_sock_destructor(struct sock *sk)
@@ -502,6 +504,12 @@ static void unix_sock_destructor(struct sock *sk)
skb_queue_purge(&sk->sk_receive_queue);
+#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
+ if (u->oob_skb) {
+ kfree_skb(u->oob_skb);
+ u->oob_skb = NULL;
+ }
+#endif
WARN_ON(refcount_read(&sk->sk_wmem_alloc));
WARN_ON(!sk_unhashed(sk));
WARN_ON(sk->sk_socket);
@@ -669,6 +677,10 @@ static ssize_t unix_stream_splice_read(struct socket *, loff_t *ppos,
unsigned int flags);
static int unix_dgram_sendmsg(struct socket *, struct msghdr *, size_t);
static int unix_dgram_recvmsg(struct socket *, struct msghdr *, size_t, int);
+static int unix_read_sock(struct sock *sk, read_descriptor_t *desc,
+ sk_read_actor_t recv_actor);
+static int unix_stream_read_sock(struct sock *sk, read_descriptor_t *desc,
+ sk_read_actor_t recv_actor);
static int unix_dgram_connect(struct socket *, struct sockaddr *,
int, int);
static int unix_seqpacket_sendmsg(struct socket *, struct msghdr *, size_t);
@@ -722,6 +734,7 @@ static const struct proto_ops unix_stream_ops = {
.shutdown = unix_shutdown,
.sendmsg = unix_stream_sendmsg,
.recvmsg = unix_stream_recvmsg,
+ .read_sock = unix_stream_read_sock,
.mmap = sock_no_mmap,
.sendpage = unix_stream_sendpage,
.splice_read = unix_stream_splice_read,
@@ -746,6 +759,7 @@ static const struct proto_ops unix_dgram_ops = {
.listen = sock_no_listen,
.shutdown = unix_shutdown,
.sendmsg = unix_dgram_sendmsg,
+ .read_sock = unix_read_sock,
.recvmsg = unix_dgram_recvmsg,
.mmap = sock_no_mmap,
.sendpage = sock_no_sendpage,
@@ -777,13 +791,42 @@ static const struct proto_ops unix_seqpacket_ops = {
.show_fdinfo = unix_show_fdinfo,
};
-static struct proto unix_proto = {
- .name = "UNIX",
+static void unix_close(struct sock *sk, long timeout)
+{
+ /* Nothing to do here, unix socket does not need a ->close().
+ * This is merely for sockmap.
+ */
+}
+
+static void unix_unhash(struct sock *sk)
+{
+ /* Nothing to do here, unix socket does not need a ->unhash().
+ * This is merely for sockmap.
+ */
+}
+
+struct proto unix_dgram_proto = {
+ .name = "UNIX-DGRAM",
.owner = THIS_MODULE,
.obj_size = sizeof(struct unix_sock),
+ .close = unix_close,
+#ifdef CONFIG_BPF_SYSCALL
+ .psock_update_sk_prot = unix_dgram_bpf_update_proto,
+#endif
};
-static struct sock *unix_create1(struct net *net, struct socket *sock, int kern)
+struct proto unix_stream_proto = {
+ .name = "UNIX-STREAM",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct unix_sock),
+ .close = unix_close,
+ .unhash = unix_unhash,
+#ifdef CONFIG_BPF_SYSCALL
+ .psock_update_sk_prot = unix_stream_bpf_update_proto,
+#endif
+};
+
+static struct sock *unix_create1(struct net *net, struct socket *sock, int kern, int type)
{
struct sock *sk = NULL;
struct unix_sock *u;
@@ -792,7 +835,11 @@ static struct sock *unix_create1(struct net *net, struct socket *sock, int kern)
if (atomic_long_read(&unix_nr_socks) > 2 * get_max_files())
goto out;
- sk = sk_alloc(net, PF_UNIX, GFP_KERNEL, &unix_proto, kern);
+ if (type == SOCK_STREAM)
+ sk = sk_alloc(net, PF_UNIX, GFP_KERNEL, &unix_stream_proto, kern);
+ else /*dgram and seqpacket */
+ sk = sk_alloc(net, PF_UNIX, GFP_KERNEL, &unix_dgram_proto, kern);
+
if (!sk)
goto out;
@@ -854,7 +901,7 @@ static int unix_create(struct net *net, struct socket *sock, int protocol,
return -ESOCKTNOSUPPORT;
}
- return unix_create1(net, sock, kern) ? 0 : -ENOMEM;
+ return unix_create1(net, sock, kern, sock->type) ? 0 : -ENOMEM;
}
static int unix_release(struct socket *sock)
@@ -864,6 +911,7 @@ static int unix_release(struct socket *sock)
if (!sk)
return 0;
+ sk->sk_prot->close(sk, 0);
unix_release_sock(sk, 0);
sock->sk = NULL;
@@ -1174,6 +1222,7 @@ restart:
if (err)
goto out_unlock;
+ sk->sk_state = other->sk_state = TCP_ESTABLISHED;
} else {
/*
* 1003.1g breaking connected state with AF_UNSPEC
@@ -1187,7 +1236,10 @@ restart:
*/
if (unix_peer(sk)) {
struct sock *old_peer = unix_peer(sk);
+
unix_peer(sk) = other;
+ if (!other)
+ sk->sk_state = TCP_CLOSE;
unix_dgram_peer_wake_disconnect_wakeup(sk, old_peer);
unix_state_double_unlock(sk, other);
@@ -1199,6 +1251,7 @@ restart:
unix_peer(sk) = other;
unix_state_double_unlock(sk, other);
}
+
return 0;
out_unlock:
@@ -1264,7 +1317,7 @@ static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
err = -ENOMEM;
/* create new sock for complete connection */
- newsk = unix_create1(sock_net(sk), NULL, 0);
+ newsk = unix_create1(sock_net(sk), NULL, 0, sock->type);
if (newsk == NULL)
goto out;
@@ -1431,12 +1484,10 @@ static int unix_socketpair(struct socket *socka, struct socket *sockb)
init_peercred(ska);
init_peercred(skb);
- if (ska->sk_type != SOCK_DGRAM) {
- ska->sk_state = TCP_ESTABLISHED;
- skb->sk_state = TCP_ESTABLISHED;
- socka->state = SS_CONNECTED;
- sockb->state = SS_CONNECTED;
- }
+ ska->sk_state = TCP_ESTABLISHED;
+ skb->sk_state = TCP_ESTABLISHED;
+ socka->state = SS_CONNECTED;
+ sockb->state = SS_CONNECTED;
return 0;
}
@@ -1782,6 +1833,7 @@ restart_locked:
unix_state_unlock(sk);
+ sk->sk_state = TCP_CLOSE;
unix_dgram_disconnected(sk, other);
sock_put(other);
err = -ECONNREFUSED;
@@ -1872,6 +1924,53 @@ out:
*/
#define UNIX_SKB_FRAGS_SZ (PAGE_SIZE << get_order(32768))
+#if (IS_ENABLED(CONFIG_AF_UNIX_OOB))
+static int queue_oob(struct socket *sock, struct msghdr *msg, struct sock *other)
+{
+ struct unix_sock *ousk = unix_sk(other);
+ struct sk_buff *skb;
+ int err = 0;
+
+ skb = sock_alloc_send_skb(sock->sk, 1, msg->msg_flags & MSG_DONTWAIT, &err);
+
+ if (!skb)
+ return err;
+
+ skb_put(skb, 1);
+ err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, 1);
+
+ if (err) {
+ kfree_skb(skb);
+ return err;
+ }
+
+ unix_state_lock(other);
+
+ if (sock_flag(other, SOCK_DEAD) ||
+ (other->sk_shutdown & RCV_SHUTDOWN)) {
+ unix_state_unlock(other);
+ kfree_skb(skb);
+ return -EPIPE;
+ }
+
+ maybe_add_creds(skb, sock, other);
+ skb_get(skb);
+
+ if (ousk->oob_skb)
+ consume_skb(ousk->oob_skb);
+
+ ousk->oob_skb = skb;
+
+ scm_stat_add(other, skb);
+ skb_queue_tail(&other->sk_receive_queue, skb);
+ sk_send_sigurg(other);
+ unix_state_unlock(other);
+ other->sk_data_ready(other);
+
+ return err;
+}
+#endif
+
static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg,
size_t len)
{
@@ -1890,8 +1989,14 @@ static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg,
return err;
err = -EOPNOTSUPP;
- if (msg->msg_flags&MSG_OOB)
- goto out_err;
+ if (msg->msg_flags & MSG_OOB) {
+#if (IS_ENABLED(CONFIG_AF_UNIX_OOB))
+ if (len)
+ len--;
+ else
+#endif
+ goto out_err;
+ }
if (msg->msg_namelen) {
err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP;
@@ -1956,6 +2061,15 @@ static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg,
sent += size;
}
+#if (IS_ENABLED(CONFIG_AF_UNIX_OOB))
+ if (msg->msg_flags & MSG_OOB) {
+ err = queue_oob(sock, msg, other);
+ if (err)
+ goto out_err;
+ sent++;
+ }
+#endif
+
scm_destroy(&scm);
return sent;
@@ -2128,11 +2242,11 @@ static void unix_copy_addr(struct msghdr *msg, struct sock *sk)
}
}
-static int unix_dgram_recvmsg(struct socket *sock, struct msghdr *msg,
- size_t size, int flags)
+int __unix_dgram_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
+ int flags)
{
struct scm_cookie scm;
- struct sock *sk = sock->sk;
+ struct socket *sock = sk->sk_socket;
struct unix_sock *u = unix_sk(sk);
struct sk_buff *skb, *last;
long timeo;
@@ -2235,6 +2349,55 @@ out:
return err;
}
+static int unix_dgram_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
+ int flags)
+{
+ struct sock *sk = sock->sk;
+
+#ifdef CONFIG_BPF_SYSCALL
+ const struct proto *prot = READ_ONCE(sk->sk_prot);
+
+ if (prot != &unix_dgram_proto)
+ return prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
+ flags & ~MSG_DONTWAIT, NULL);
+#endif
+ return __unix_dgram_recvmsg(sk, msg, size, flags);
+}
+
+static int unix_read_sock(struct sock *sk, read_descriptor_t *desc,
+ sk_read_actor_t recv_actor)
+{
+ int copied = 0;
+
+ while (1) {
+ struct unix_sock *u = unix_sk(sk);
+ struct sk_buff *skb;
+ int used, err;
+
+ mutex_lock(&u->iolock);
+ skb = skb_recv_datagram(sk, 0, 1, &err);
+ mutex_unlock(&u->iolock);
+ if (!skb)
+ return err;
+
+ used = recv_actor(desc, skb, 0, skb->len);
+ if (used <= 0) {
+ if (!copied)
+ copied = used;
+ kfree_skb(skb);
+ break;
+ } else if (used <= skb->len) {
+ copied += used;
+ }
+
+ kfree_skb(skb);
+ if (!desc->count)
+ break;
+ }
+
+ return copied;
+}
+
/*
* Sleep until more data has arrived. But check for races..
*/
@@ -2294,6 +2457,86 @@ struct unix_stream_read_state {
unsigned int splice_flags;
};
+#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
+static int unix_stream_recv_urg(struct unix_stream_read_state *state)
+{
+ struct socket *sock = state->socket;
+ struct sock *sk = sock->sk;
+ struct unix_sock *u = unix_sk(sk);
+ int chunk = 1;
+ struct sk_buff *oob_skb;
+
+ mutex_lock(&u->iolock);
+ unix_state_lock(sk);
+
+ if (sock_flag(sk, SOCK_URGINLINE) || !u->oob_skb) {
+ unix_state_unlock(sk);
+ mutex_unlock(&u->iolock);
+ return -EINVAL;
+ }
+
+ oob_skb = u->oob_skb;
+
+ if (!(state->flags & MSG_PEEK)) {
+ u->oob_skb = NULL;
+ }
+
+ unix_state_unlock(sk);
+
+ chunk = state->recv_actor(oob_skb, 0, chunk, state);
+
+ if (!(state->flags & MSG_PEEK)) {
+ UNIXCB(oob_skb).consumed += 1;
+ kfree_skb(oob_skb);
+ }
+
+ mutex_unlock(&u->iolock);
+
+ if (chunk < 0)
+ return -EFAULT;
+
+ state->msg->msg_flags |= MSG_OOB;
+ return 1;
+}
+
+static struct sk_buff *manage_oob(struct sk_buff *skb, struct sock *sk,
+ int flags, int copied)
+{
+ struct unix_sock *u = unix_sk(sk);
+
+ if (!unix_skb_len(skb) && !(flags & MSG_PEEK)) {
+ skb_unlink(skb, &sk->sk_receive_queue);
+ consume_skb(skb);
+ skb = NULL;
+ } else {
+ if (skb == u->oob_skb) {
+ if (copied) {
+ skb = NULL;
+ } else if (sock_flag(sk, SOCK_URGINLINE)) {
+ if (!(flags & MSG_PEEK)) {
+ u->oob_skb = NULL;
+ consume_skb(skb);
+ }
+ } else if (!(flags & MSG_PEEK)) {
+ skb_unlink(skb, &sk->sk_receive_queue);
+ consume_skb(skb);
+ skb = skb_peek(&sk->sk_receive_queue);
+ }
+ }
+ }
+ return skb;
+}
+#endif
+
+static int unix_stream_read_sock(struct sock *sk, read_descriptor_t *desc,
+ sk_read_actor_t recv_actor)
+{
+ if (unlikely(sk->sk_state != TCP_ESTABLISHED))
+ return -ENOTCONN;
+
+ return unix_read_sock(sk, desc, recv_actor);
+}
+
static int unix_stream_read_generic(struct unix_stream_read_state *state,
bool freezable)
{
@@ -2319,6 +2562,9 @@ static int unix_stream_read_generic(struct unix_stream_read_state *state,
if (unlikely(flags & MSG_OOB)) {
err = -EOPNOTSUPP;
+#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
+ err = unix_stream_recv_urg(state);
+#endif
goto out;
}
@@ -2347,6 +2593,18 @@ redo:
}
last = skb = skb_peek(&sk->sk_receive_queue);
last_len = last ? last->len : 0;
+
+#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
+ if (skb) {
+ skb = manage_oob(skb, sk, flags, copied);
+ if (!skb) {
+ unix_state_unlock(sk);
+ if (copied)
+ break;
+ goto redo;
+ }
+ }
+#endif
again:
if (skb == NULL) {
if (copied >= target)
@@ -2504,6 +2762,20 @@ static int unix_stream_read_actor(struct sk_buff *skb,
return ret ?: chunk;
}
+int __unix_stream_recvmsg(struct sock *sk, struct msghdr *msg,
+ size_t size, int flags)
+{
+ struct unix_stream_read_state state = {
+ .recv_actor = unix_stream_read_actor,
+ .socket = sk->sk_socket,
+ .msg = msg,
+ .size = size,
+ .flags = flags
+ };
+
+ return unix_stream_read_generic(&state, true);
+}
+
static int unix_stream_recvmsg(struct socket *sock, struct msghdr *msg,
size_t size, int flags)
{
@@ -2515,6 +2787,14 @@ static int unix_stream_recvmsg(struct socket *sock, struct msghdr *msg,
.flags = flags
};
+#ifdef CONFIG_BPF_SYSCALL
+ struct sock *sk = sock->sk;
+ const struct proto *prot = READ_ONCE(sk->sk_prot);
+
+ if (prot != &unix_stream_proto)
+ return prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
+ flags & ~MSG_DONTWAIT, NULL);
+#endif
return unix_stream_read_generic(&state, true);
}
@@ -2575,7 +2855,10 @@ static int unix_shutdown(struct socket *sock, int mode)
(sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET)) {
int peer_mode = 0;
+ const struct proto *prot = READ_ONCE(other->sk_prot);
+ if (prot->unhash)
+ prot->unhash(other);
if (mode&RCV_SHUTDOWN)
peer_mode |= SEND_SHUTDOWN;
if (mode&SEND_SHUTDOWN)
@@ -2584,10 +2867,12 @@ static int unix_shutdown(struct socket *sock, int mode)
other->sk_shutdown |= peer_mode;
unix_state_unlock(other);
other->sk_state_change(other);
- if (peer_mode == SHUTDOWN_MASK)
+ if (peer_mode == SHUTDOWN_MASK) {
sk_wake_async(other, SOCK_WAKE_WAITD, POLL_HUP);
- else if (peer_mode & RCV_SHUTDOWN)
+ other->sk_state = TCP_CLOSE;
+ } else if (peer_mode & RCV_SHUTDOWN) {
sk_wake_async(other, SOCK_WAKE_WAITD, POLL_IN);
+ }
}
if (other)
sock_put(other);
@@ -2682,6 +2967,20 @@ static int unix_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
case SIOCUNIXFILE:
err = unix_open_file(sk);
break;
+#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
+ case SIOCATMARK:
+ {
+ struct sk_buff *skb;
+ struct unix_sock *u = unix_sk(sk);
+ int answ = 0;
+
+ skb = skb_peek(&sk->sk_receive_queue);
+ if (skb && skb == u->oob_skb)
+ answ = 1;
+ err = put_user(answ, (int __user *)arg);
+ }
+ break;
+#endif
default:
err = -ENOIOCTLCMD;
break;
@@ -2918,6 +3217,64 @@ static const struct seq_operations unix_seq_ops = {
.stop = unix_seq_stop,
.show = unix_seq_show,
};
+
+#if IS_BUILTIN(CONFIG_UNIX) && defined(CONFIG_BPF_SYSCALL)
+struct bpf_iter__unix {
+ __bpf_md_ptr(struct bpf_iter_meta *, meta);
+ __bpf_md_ptr(struct unix_sock *, unix_sk);
+ uid_t uid __aligned(8);
+};
+
+static int unix_prog_seq_show(struct bpf_prog *prog, struct bpf_iter_meta *meta,
+ struct unix_sock *unix_sk, uid_t uid)
+{
+ struct bpf_iter__unix ctx;
+
+ meta->seq_num--; /* skip SEQ_START_TOKEN */
+ ctx.meta = meta;
+ ctx.unix_sk = unix_sk;
+ ctx.uid = uid;
+ return bpf_iter_run_prog(prog, &ctx);
+}
+
+static int bpf_iter_unix_seq_show(struct seq_file *seq, void *v)
+{
+ struct bpf_iter_meta meta;
+ struct bpf_prog *prog;
+ struct sock *sk = v;
+ uid_t uid;
+
+ if (v == SEQ_START_TOKEN)
+ return 0;
+
+ uid = from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk));
+ meta.seq = seq;
+ prog = bpf_iter_get_info(&meta, false);
+ return unix_prog_seq_show(prog, &meta, v, uid);
+}
+
+static void bpf_iter_unix_seq_stop(struct seq_file *seq, void *v)
+{
+ struct bpf_iter_meta meta;
+ struct bpf_prog *prog;
+
+ if (!v) {
+ meta.seq = seq;
+ prog = bpf_iter_get_info(&meta, true);
+ if (prog)
+ (void)unix_prog_seq_show(prog, &meta, v, 0);
+ }
+
+ unix_seq_stop(seq, v);
+}
+
+static const struct seq_operations bpf_iter_unix_seq_ops = {
+ .start = unix_seq_start,
+ .next = unix_seq_next,
+ .stop = bpf_iter_unix_seq_stop,
+ .show = bpf_iter_unix_seq_show,
+};
+#endif
#endif
static const struct net_proto_family unix_family_ops = {
@@ -2958,13 +3315,48 @@ static struct pernet_operations unix_net_ops = {
.exit = unix_net_exit,
};
+#if IS_BUILTIN(CONFIG_UNIX) && defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)
+DEFINE_BPF_ITER_FUNC(unix, struct bpf_iter_meta *meta,
+ struct unix_sock *unix_sk, uid_t uid)
+
+static const struct bpf_iter_seq_info unix_seq_info = {
+ .seq_ops = &bpf_iter_unix_seq_ops,
+ .init_seq_private = bpf_iter_init_seq_net,
+ .fini_seq_private = bpf_iter_fini_seq_net,
+ .seq_priv_size = sizeof(struct seq_net_private),
+};
+
+static struct bpf_iter_reg unix_reg_info = {
+ .target = "unix",
+ .ctx_arg_info_size = 1,
+ .ctx_arg_info = {
+ { offsetof(struct bpf_iter__unix, unix_sk),
+ PTR_TO_BTF_ID_OR_NULL },
+ },
+ .seq_info = &unix_seq_info,
+};
+
+static void __init bpf_iter_register(void)
+{
+ unix_reg_info.ctx_arg_info[0].btf_id = btf_sock_ids[BTF_SOCK_TYPE_UNIX];
+ if (bpf_iter_reg_target(&unix_reg_info))
+ pr_warn("Warning: could not register bpf iterator unix\n");
+}
+#endif
+
static int __init af_unix_init(void)
{
int rc = -1;
BUILD_BUG_ON(sizeof(struct unix_skb_parms) > sizeof_field(struct sk_buff, cb));
- rc = proto_register(&unix_proto, 1);
+ rc = proto_register(&unix_dgram_proto, 1);
+ if (rc != 0) {
+ pr_crit("%s: Cannot create unix_sock SLAB cache!\n", __func__);
+ goto out;
+ }
+
+ rc = proto_register(&unix_stream_proto, 1);
if (rc != 0) {
pr_crit("%s: Cannot create unix_sock SLAB cache!\n", __func__);
goto out;
@@ -2972,6 +3364,12 @@ static int __init af_unix_init(void)
sock_register(&unix_family_ops);
register_pernet_subsys(&unix_net_ops);
+ unix_bpf_build_proto();
+
+#if IS_BUILTIN(CONFIG_UNIX) && defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)
+ bpf_iter_register();
+#endif
+
out:
return rc;
}
@@ -2979,7 +3377,8 @@ out:
static void __exit af_unix_exit(void)
{
sock_unregister(PF_UNIX);
- proto_unregister(&unix_proto);
+ proto_unregister(&unix_dgram_proto);
+ proto_unregister(&unix_stream_proto);
unregister_pernet_subsys(&unix_net_ops);
}