diff options
Diffstat (limited to 'net/unix/af_unix.c')
-rw-r--r-- | net/unix/af_unix.c | 441 |
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); } |