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Diffstat (limited to 'net/unix/af_unix.c')
-rw-r--r--net/unix/af_unix.c871
1 files changed, 514 insertions, 357 deletions
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 0be0dcb07f7b..768098dec231 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -77,46 +77,40 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/signal.h>
-#include <linux/sched/signal.h>
-#include <linux/errno.h>
-#include <linux/string.h>
-#include <linux/stat.h>
+#include <linux/bpf-cgroup.h>
+#include <linux/btf_ids.h>
#include <linux/dcache.h>
-#include <linux/namei.h>
-#include <linux/socket.h>
-#include <linux/un.h>
+#include <linux/errno.h>
#include <linux/fcntl.h>
+#include <linux/file.h>
#include <linux/filter.h>
-#include <linux/termios.h>
-#include <linux/sockios.h>
-#include <linux/net.h>
-#include <linux/in.h>
#include <linux/fs.h>
-#include <linux/slab.h>
-#include <linux/uaccess.h>
-#include <linux/skbuff.h>
-#include <linux/netdevice.h>
-#include <net/net_namespace.h>
-#include <net/sock.h>
-#include <net/tcp_states.h>
-#include <net/af_unix.h>
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
-#include <net/scm.h>
+#include <linux/fs_struct.h>
#include <linux/init.h>
-#include <linux/poll.h>
-#include <linux/rtnetlink.h>
+#include <linux/kernel.h>
#include <linux/mount.h>
-#include <net/checksum.h>
+#include <linux/namei.h>
+#include <linux/net.h>
+#include <linux/pidfs.h>
+#include <linux/poll.h>
+#include <linux/proc_fs.h>
+#include <linux/sched/signal.h>
#include <linux/security.h>
+#include <linux/seq_file.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/socket.h>
#include <linux/splice.h>
-#include <linux/freezer.h>
-#include <linux/file.h>
-#include <linux/btf_ids.h>
-#include <linux/bpf-cgroup.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+#include <net/af_unix.h>
+#include <net/net_namespace.h>
+#include <net/scm.h>
+#include <net/tcp_states.h>
+#include <uapi/linux/sockios.h>
+#include <uapi/linux/termios.h>
+
+#include "af_unix.h"
static atomic_long_t unix_nr_socks;
static struct hlist_head bsd_socket_buckets[UNIX_HASH_SIZE / 2];
@@ -286,14 +280,9 @@ static inline bool unix_secdata_eq(struct scm_cookie *scm, struct sk_buff *skb)
}
#endif /* CONFIG_SECURITY_NETWORK */
-static inline int unix_our_peer(struct sock *sk, struct sock *osk)
-{
- return unix_peer(osk) == sk;
-}
-
static inline int unix_may_send(struct sock *sk, struct sock *osk)
{
- return unix_peer(osk) == NULL || unix_our_peer(sk, osk);
+ return !unix_peer(osk) || unix_peer(osk) == sk;
}
static inline int unix_recvq_full_lockless(const struct sock *sk)
@@ -627,7 +616,9 @@ static void unix_write_space(struct sock *sk)
static void unix_dgram_disconnected(struct sock *sk, struct sock *other)
{
if (!skb_queue_empty(&sk->sk_receive_queue)) {
- skb_queue_purge(&sk->sk_receive_queue);
+ skb_queue_purge_reason(&sk->sk_receive_queue,
+ SKB_DROP_REASON_UNIX_DISCONNECT);
+
wake_up_interruptible_all(&unix_sk(sk)->peer_wait);
/* If one link of bidirectional dgram pipe is disconnected,
@@ -645,7 +636,7 @@ static void unix_sock_destructor(struct sock *sk)
{
struct unix_sock *u = unix_sk(sk);
- skb_queue_purge(&sk->sk_receive_queue);
+ skb_queue_purge_reason(&sk->sk_receive_queue, SKB_DROP_REASON_SOCKET_CLOSE);
DEBUG_NET_WARN_ON_ONCE(refcount_read(&sk->sk_wmem_alloc));
DEBUG_NET_WARN_ON_ONCE(!sk_unhashed(sk));
@@ -666,6 +657,11 @@ static void unix_sock_destructor(struct sock *sk)
#endif
}
+static unsigned int unix_skb_len(const struct sk_buff *skb)
+{
+ return skb->len - UNIXCB(skb).consumed;
+}
+
static void unix_release_sock(struct sock *sk, int embrion)
{
struct unix_sock *u = unix_sk(sk);
@@ -693,20 +689,23 @@ static void unix_release_sock(struct sock *sk, int embrion)
unix_state_unlock(sk);
#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
- if (u->oob_skb) {
- kfree_skb(u->oob_skb);
- u->oob_skb = NULL;
- }
+ u->oob_skb = NULL;
#endif
wake_up_interruptible_all(&u->peer_wait);
if (skpair != NULL) {
if (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) {
+ struct sk_buff *skb = skb_peek(&sk->sk_receive_queue);
+
+#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
+ if (skb && !unix_skb_len(skb))
+ skb = skb_peek_next(skb, &sk->sk_receive_queue);
+#endif
unix_state_lock(skpair);
/* No more writes */
WRITE_ONCE(skpair->sk_shutdown, SHUTDOWN_MASK);
- if (!skb_queue_empty_lockless(&sk->sk_receive_queue) || embrion)
+ if (skb || embrion)
WRITE_ONCE(skpair->sk_err, ECONNRESET);
unix_state_unlock(skpair);
skpair->sk_state_change(skpair);
@@ -723,8 +722,8 @@ static void unix_release_sock(struct sock *sk, int embrion)
if (state == TCP_LISTEN)
unix_release_sock(skb->sk, 1);
- /* passed fds are erased in the kfree_skb hook */
- kfree_skb(skb);
+ /* passed fds are erased in the kfree_skb hook */
+ kfree_skb_reason(skb, SKB_DROP_REASON_SOCKET_CLOSE);
}
if (path.dentry)
@@ -749,13 +748,47 @@ static void unix_release_sock(struct sock *sk, int embrion)
unix_gc(); /* Garbage collect fds */
}
-static void init_peercred(struct sock *sk)
+struct unix_peercred {
+ struct pid *peer_pid;
+ const struct cred *peer_cred;
+};
+
+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 = get_pid(pid);
+ peercred->peer_cred = get_current_cred();
+ }
+ return err;
+}
+
+static void drop_peercred(struct unix_peercred *peercred)
+{
+ const struct cred *cred = NULL;
+ struct pid *pid = NULL;
+
+ might_sleep();
+
+ swap(peercred->peer_pid, 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 = get_pid(task_tgid(current));
- sk->sk_peer_cred = get_current_cred();
+ sk->sk_peer_pid = peercred->peer_pid;
+ sk->sk_peer_cred = peercred->peer_cred;
}
-static void update_peercred(struct sock *sk)
+static void update_peercred(struct sock *sk, struct unix_peercred *peercred)
{
const struct cred *old_cred;
struct pid *old_pid;
@@ -763,11 +796,11 @@ static void update_peercred(struct sock *sk)
spin_lock(&sk->sk_peer_lock);
old_pid = sk->sk_peer_pid;
old_cred = sk->sk_peer_cred;
- init_peercred(sk);
+ init_peercred(sk, peercred);
spin_unlock(&sk->sk_peer_lock);
- put_pid(old_pid);
- put_cred(old_cred);
+ peercred->peer_pid = old_pid;
+ peercred->peer_cred = old_cred;
}
static void copy_peercred(struct sock *sk, struct sock *peersk)
@@ -780,11 +813,17 @@ static void copy_peercred(struct sock *sk, struct sock *peersk)
spin_unlock(&sk->sk_peer_lock);
}
+static bool unix_may_passcred(const struct sock *sk)
+{
+ return sk->sk_scm_credentials || sk->sk_scm_pidfd;
+}
+
static int unix_listen(struct socket *sock, int backlog)
{
int err;
struct sock *sk = sock->sk;
struct unix_sock *u = unix_sk(sk);
+ struct unix_peercred peercred = {};
err = -EOPNOTSUPP;
if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
@@ -792,6 +831,9 @@ static int unix_listen(struct socket *sock, int backlog)
err = -EINVAL;
if (!READ_ONCE(u->addr))
goto out; /* No listens on an unbound socket */
+ err = prepare_peercred(&peercred);
+ if (err)
+ goto out;
unix_state_lock(sk);
if (sk->sk_state != TCP_CLOSE && sk->sk_state != TCP_LISTEN)
goto out_unlock;
@@ -801,11 +843,12 @@ static int unix_listen(struct socket *sock, int backlog)
WRITE_ONCE(sk->sk_state, TCP_LISTEN);
/* set credentials so connect can copy them */
- update_peercred(sk);
+ update_peercred(sk, &peercred);
err = 0;
out_unlock:
unix_state_unlock(sk);
+ drop_peercred(&peercred);
out:
return err;
}
@@ -886,6 +929,52 @@ static void unix_show_fdinfo(struct seq_file *m, struct socket *sock)
#define unix_show_fdinfo NULL
#endif
+static bool unix_custom_sockopt(int optname)
+{
+ switch (optname) {
+ case SO_INQ:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static int unix_setsockopt(struct socket *sock, int level, int optname,
+ sockptr_t optval, unsigned int optlen)
+{
+ struct unix_sock *u = unix_sk(sock->sk);
+ struct sock *sk = sock->sk;
+ int val;
+
+ if (level != SOL_SOCKET)
+ return -EOPNOTSUPP;
+
+ if (!unix_custom_sockopt(optname))
+ return sock_setsockopt(sock, level, optname, optval, optlen);
+
+ if (optlen != sizeof(int))
+ return -EINVAL;
+
+ if (copy_from_sockptr(&val, optval, sizeof(val)))
+ return -EFAULT;
+
+ switch (optname) {
+ case SO_INQ:
+ if (sk->sk_type != SOCK_STREAM)
+ return -EINVAL;
+
+ if (val > 1 || val < 0)
+ return -EINVAL;
+
+ WRITE_ONCE(u->recvmsg_inq, val);
+ break;
+ default:
+ return -ENOPROTOOPT;
+ }
+
+ return 0;
+}
+
static const struct proto_ops unix_stream_ops = {
.family = PF_UNIX,
.owner = THIS_MODULE,
@@ -902,6 +991,7 @@ static const struct proto_ops unix_stream_ops = {
#endif
.listen = unix_listen,
.shutdown = unix_shutdown,
+ .setsockopt = unix_setsockopt,
.sendmsg = unix_stream_sendmsg,
.recvmsg = unix_stream_recvmsg,
.read_skb = unix_stream_read_skb,
@@ -965,13 +1055,6 @@ static void unix_close(struct sock *sk, long timeout)
*/
}
-static void unix_unhash(struct sock *sk)
-{
- /* Nothing to do here, unix socket does not need a ->unhash().
- * This is merely for sockmap.
- */
-}
-
static bool unix_bpf_bypass_getsockopt(int level, int optname)
{
if (level == SOL_SOCKET) {
@@ -1002,7 +1085,6 @@ struct proto unix_stream_proto = {
.owner = THIS_MODULE,
.obj_size = sizeof(struct unix_sock),
.close = unix_close,
- .unhash = unix_unhash,
.bpf_bypass_getsockopt = unix_bpf_bypass_getsockopt,
#ifdef CONFIG_BPF_SYSCALL
.psock_update_sk_prot = unix_stream_bpf_update_proto,
@@ -1033,6 +1115,7 @@ static struct sock *unix_create1(struct net *net, struct socket *sock, int kern,
sock_init_data(sock, sk);
+ sk->sk_scm_rights = 1;
sk->sk_hash = unix_unbound_hash(sk);
sk->sk_allocation = GFP_KERNEL_ACCOUNT;
sk->sk_write_space = unix_write_space;
@@ -1075,6 +1158,7 @@ static int unix_create(struct net *net, struct socket *sock, int protocol,
switch (sock->type) {
case SOCK_STREAM:
+ set_bit(SOCK_CUSTOM_SOCKOPT, &sock->flags);
sock->ops = &unix_stream_ops;
break;
/*
@@ -1116,7 +1200,7 @@ static int unix_release(struct socket *sock)
}
static struct sock *unix_find_bsd(struct sockaddr_un *sunaddr, int addr_len,
- int type)
+ int type, int flags)
{
struct inode *inode;
struct path path;
@@ -1124,13 +1208,39 @@ static struct sock *unix_find_bsd(struct sockaddr_un *sunaddr, int addr_len,
int err;
unix_mkname_bsd(sunaddr, addr_len);
- err = kern_path(sunaddr->sun_path, LOOKUP_FOLLOW, &path);
- if (err)
- goto fail;
- err = path_permission(&path, MAY_WRITE);
- if (err)
- goto path_put;
+ if (flags & SOCK_COREDUMP) {
+ const struct cred *cred;
+ struct cred *kcred;
+ struct path root;
+
+ kcred = prepare_kernel_cred(&init_task);
+ if (!kcred) {
+ err = -ENOMEM;
+ goto fail;
+ }
+
+ task_lock(&init_task);
+ get_fs_root(init_task.fs, &root);
+ task_unlock(&init_task);
+
+ cred = override_creds(kcred);
+ err = vfs_path_lookup(root.dentry, root.mnt, sunaddr->sun_path,
+ LOOKUP_BENEATH | LOOKUP_NO_SYMLINKS |
+ LOOKUP_NO_MAGICLINKS, &path);
+ put_cred(revert_creds(cred));
+ path_put(&root);
+ if (err)
+ goto fail;
+ } else {
+ err = kern_path(sunaddr->sun_path, LOOKUP_FOLLOW, &path);
+ if (err)
+ goto fail;
+
+ err = path_permission(&path, MAY_WRITE);
+ if (err)
+ goto path_put;
+ }
err = -ECONNREFUSED;
inode = d_backing_inode(path.dentry);
@@ -1180,12 +1290,12 @@ static struct sock *unix_find_abstract(struct net *net,
static struct sock *unix_find_other(struct net *net,
struct sockaddr_un *sunaddr,
- int addr_len, int type)
+ int addr_len, int type, int flags)
{
struct sock *sk;
if (sunaddr->sun_path[0])
- sk = unix_find_bsd(sunaddr, addr_len, type);
+ sk = unix_find_bsd(sunaddr, addr_len, type, flags);
else
sk = unix_find_abstract(net, sunaddr, addr_len, type);
@@ -1277,7 +1387,7 @@ static int unix_bind_bsd(struct sock *sk, struct sockaddr_un *sunaddr,
* Get the parent directory, calculate the hash for last
* component.
*/
- dentry = kern_path_create(AT_FDCWD, addr->name->sun_path, &parent, 0);
+ dentry = start_creating_path(AT_FDCWD, addr->name->sun_path, &parent, 0);
if (IS_ERR(dentry)) {
err = PTR_ERR(dentry);
goto out;
@@ -1307,7 +1417,7 @@ static int unix_bind_bsd(struct sock *sk, struct sockaddr_un *sunaddr,
unix_table_double_unlock(net, old_hash, new_hash);
unix_insert_bsd_socket(sk);
mutex_unlock(&u->bindlock);
- done_path_create(&parent, dentry);
+ end_creating_path(&parent, dentry);
return 0;
out_unlock:
@@ -1317,7 +1427,7 @@ out_unlink:
/* failed after successful mknod? unlink what we'd created... */
vfs_unlink(idmap, d_inode(parent.dentry), dentry, NULL);
out_path:
- done_path_create(&parent, dentry);
+ end_creating_path(&parent, dentry);
out:
unix_release_addr(addr);
return err == -EEXIST ? -EADDRINUSE : err;
@@ -1434,16 +1544,14 @@ static int unix_dgram_connect(struct socket *sock, struct sockaddr *addr,
if (err)
goto out;
- if ((test_bit(SOCK_PASSCRED, &sock->flags) ||
- test_bit(SOCK_PASSPIDFD, &sock->flags)) &&
- !READ_ONCE(unix_sk(sk)->addr)) {
+ if (unix_may_passcred(sk) && !READ_ONCE(unix_sk(sk)->addr)) {
err = unix_autobind(sk);
if (err)
goto out;
}
restart:
- other = unix_find_other(sock_net(sk), sunaddr, alen, sock->type);
+ other = unix_find_other(sock_net(sk), sunaddr, alen, sock->type, 0);
if (IS_ERR(other)) {
err = PTR_ERR(other);
goto out;
@@ -1514,7 +1622,6 @@ out:
}
static long unix_wait_for_peer(struct sock *other, long timeo)
- __releases(&unix_sk(other)->lock)
{
struct unix_sock *u = unix_sk(other);
int sched;
@@ -1541,6 +1648,7 @@ static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr;
struct sock *sk = sock->sk, *newsk = NULL, *other = NULL;
struct unix_sock *u = unix_sk(sk), *newu, *otheru;
+ struct unix_peercred peercred = {};
struct net *net = sock_net(sk);
struct sk_buff *skb = NULL;
unsigned char state;
@@ -1555,9 +1663,7 @@ static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
if (err)
goto out;
- if ((test_bit(SOCK_PASSCRED, &sock->flags) ||
- test_bit(SOCK_PASSPIDFD, &sock->flags)) &&
- !READ_ONCE(u->addr)) {
+ if (unix_may_passcred(sk) && !READ_ONCE(u->addr)) {
err = unix_autobind(sk);
if (err)
goto out;
@@ -1566,32 +1672,34 @@ static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
/* First of all allocate resources.
- If we will make it after state is locked,
- we will have to recheck all again in any case.
+ * If we will make it after state is locked,
+ * we will have to recheck all again in any case.
*/
/* create new sock for complete connection */
newsk = unix_create1(net, NULL, 0, sock->type);
if (IS_ERR(newsk)) {
err = PTR_ERR(newsk);
- newsk = NULL;
goto out;
}
- err = -ENOMEM;
+ err = prepare_peercred(&peercred);
+ if (err)
+ goto out;
/* Allocate skb for sending to listening sock */
skb = sock_wmalloc(newsk, 1, 0, GFP_KERNEL);
- if (skb == NULL)
- goto out;
+ if (!skb) {
+ err = -ENOMEM;
+ goto out_free_sk;
+ }
restart:
/* Find listening sock. */
- other = unix_find_other(net, sunaddr, addr_len, sk->sk_type);
+ other = unix_find_other(net, sunaddr, addr_len, sk->sk_type, flags);
if (IS_ERR(other)) {
err = PTR_ERR(other);
- other = NULL;
- goto out;
+ goto out_free_skb;
}
unix_state_lock(other);
@@ -1603,23 +1711,25 @@ restart:
goto restart;
}
- err = -ECONNREFUSED;
- if (other->sk_state != TCP_LISTEN)
- goto out_unlock;
- if (other->sk_shutdown & RCV_SHUTDOWN)
+ if (other->sk_state != TCP_LISTEN ||
+ other->sk_shutdown & RCV_SHUTDOWN) {
+ err = -ECONNREFUSED;
goto out_unlock;
+ }
if (unix_recvq_full_lockless(other)) {
- err = -EAGAIN;
- if (!timeo)
+ if (!timeo) {
+ err = -EAGAIN;
goto out_unlock;
+ }
timeo = unix_wait_for_peer(other, timeo);
+ sock_put(other);
err = sock_intr_errno(timeo);
if (signal_pending(current))
- goto out;
- sock_put(other);
+ goto out_free_skb;
+
goto restart;
}
@@ -1649,10 +1759,12 @@ restart:
/* The way is open! Fastly set all the necessary fields... */
sock_hold(sk);
- unix_peer(newsk) = sk;
- newsk->sk_state = TCP_ESTABLISHED;
- newsk->sk_type = sk->sk_type;
- init_peercred(newsk);
+ unix_peer(newsk) = sk;
+ newsk->sk_state = TCP_ESTABLISHED;
+ newsk->sk_type = sk->sk_type;
+ newsk->sk_scm_recv_flags = other->sk_scm_recv_flags;
+ init_peercred(newsk, &peercred);
+
newu = unix_sk(newsk);
newu->listener = other;
RCU_INIT_POINTER(newsk->sk_wq, &newu->peer_wq);
@@ -1704,29 +1816,40 @@ restart:
return 0;
out_unlock:
- if (other)
- unix_state_unlock(other);
-
+ unix_state_unlock(other);
+ sock_put(other);
+out_free_skb:
+ consume_skb(skb);
+out_free_sk:
+ unix_release_sock(newsk, 0);
out:
- kfree_skb(skb);
- if (newsk)
- unix_release_sock(newsk, 0);
- if (other)
- sock_put(other);
+ drop_peercred(&peercred);
return err;
}
static int unix_socketpair(struct socket *socka, struct socket *sockb)
{
+ struct unix_peercred ska_peercred = {}, skb_peercred = {};
struct sock *ska = socka->sk, *skb = sockb->sk;
+ int err;
+
+ err = prepare_peercred(&ska_peercred);
+ if (err)
+ return err;
+
+ err = prepare_peercred(&skb_peercred);
+ if (err) {
+ drop_peercred(&ska_peercred);
+ return err;
+ }
/* Join our sockets back to back */
sock_hold(ska);
sock_hold(skb);
unix_peer(ska) = skb;
unix_peer(skb) = ska;
- init_peercred(ska);
- init_peercred(skb);
+ init_peercred(ska, &ska_peercred);
+ init_peercred(skb, &skb_peercred);
ska->sk_state = TCP_ESTABLISHED;
skb->sk_state = TCP_ESTABLISHED;
@@ -1735,17 +1858,6 @@ static int unix_socketpair(struct socket *socka, struct socket *sockb)
return 0;
}
-static void unix_sock_inherit_flags(const struct socket *old,
- struct socket *new)
-{
- if (test_bit(SOCK_PASSCRED, &old->flags))
- set_bit(SOCK_PASSCRED, &new->flags);
- if (test_bit(SOCK_PASSPIDFD, &old->flags))
- set_bit(SOCK_PASSPIDFD, &new->flags);
- if (test_bit(SOCK_PASSSEC, &old->flags))
- set_bit(SOCK_PASSSEC, &new->flags);
-}
-
static int unix_accept(struct socket *sock, struct socket *newsock,
struct proto_accept_arg *arg)
{
@@ -1778,11 +1890,13 @@ static int unix_accept(struct socket *sock, struct socket *newsock,
skb_free_datagram(sk, skb);
wake_up_interruptible(&unix_sk(sk)->peer_wait);
+ if (tsk->sk_type == SOCK_STREAM)
+ set_bit(SOCK_CUSTOM_SOCKOPT, &newsock->flags);
+
/* attach accepted sock to socket */
unix_state_lock(tsk);
unix_update_edges(unix_sk(tsk));
newsock->state = SS_CONNECTED;
- unix_sock_inherit_flags(sock, newsock);
sock_graft(tsk, newsock);
unix_state_unlock(tsk);
return 0;
@@ -1877,7 +1991,7 @@ static void unix_destruct_scm(struct sk_buff *skb)
struct scm_cookie scm;
memset(&scm, 0, sizeof(scm));
- scm.pid = UNIXCB(skb).pid;
+ scm.pid = UNIXCB(skb).pid;
if (UNIXCB(skb).fp)
unix_detach_fds(&scm, skb);
@@ -1891,7 +2005,7 @@ static int unix_scm_to_skb(struct scm_cookie *scm, struct sk_buff *skb, bool sen
{
int err = 0;
- UNIXCB(skb).pid = get_pid(scm->pid);
+ UNIXCB(skb).pid = get_pid(scm->pid);
UNIXCB(skb).uid = scm->creds.uid;
UNIXCB(skb).gid = scm->creds.gid;
UNIXCB(skb).fp = NULL;
@@ -1903,30 +2017,46 @@ static int unix_scm_to_skb(struct scm_cookie *scm, struct sk_buff *skb, bool sen
return err;
}
-static bool unix_passcred_enabled(const struct socket *sock,
- const struct sock *other)
+static void unix_skb_to_scm(struct sk_buff *skb, struct scm_cookie *scm)
{
- return test_bit(SOCK_PASSCRED, &sock->flags) ||
- test_bit(SOCK_PASSPIDFD, &sock->flags) ||
- !other->sk_socket ||
- test_bit(SOCK_PASSCRED, &other->sk_socket->flags) ||
- test_bit(SOCK_PASSPIDFD, &other->sk_socket->flags);
+ scm_set_cred(scm, UNIXCB(skb).pid, UNIXCB(skb).uid, UNIXCB(skb).gid);
+ unix_set_secdata(scm, skb);
}
-/*
+/**
+ * unix_maybe_add_creds() - Adds current task uid/gid and struct pid to skb if needed.
+ * @skb: skb to attach creds to.
+ * @sk: Sender sock.
+ * @other: Receiver sock.
+ *
* Some apps rely on write() giving SCM_CREDENTIALS
* We include credentials if source or destination socket
* asserted SOCK_PASSCRED.
+ *
+ * Context: May sleep.
+ * Return: On success zero, on error a negative error code is returned.
*/
-static void maybe_add_creds(struct sk_buff *skb, const struct socket *sock,
- const struct sock *other)
+static int unix_maybe_add_creds(struct sk_buff *skb, const struct sock *sk,
+ const struct sock *other)
{
if (UNIXCB(skb).pid)
- return;
- if (unix_passcred_enabled(sock, other)) {
- UNIXCB(skb).pid = get_pid(task_tgid(current));
+ return 0;
+
+ if (unix_may_passcred(sk) || unix_may_passcred(other) ||
+ !other->sk_socket) {
+ struct pid *pid;
+ int err;
+
+ pid = task_tgid(current);
+ err = pidfs_register_pid(pid);
+ if (unlikely(err))
+ return err;
+
+ UNIXCB(skb).pid = get_pid(pid);
current_uid_gid(&UNIXCB(skb).uid, &UNIXCB(skb).gid);
}
+
+ return 0;
}
static bool unix_skb_scm_eq(struct sk_buff *skb,
@@ -1967,7 +2097,6 @@ static void scm_stat_del(struct sock *sk, struct sk_buff *skb)
static int unix_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
size_t len)
{
- DECLARE_SOCKADDR(struct sockaddr_un *, sunaddr, msg->msg_name);
struct sock *sk = sock->sk, *other = NULL;
struct unix_sock *u = unix_sk(sk);
struct scm_cookie scm;
@@ -1983,12 +2112,13 @@ static int unix_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
wait_for_unix_gc(scm.fp);
- err = -EOPNOTSUPP;
- if (msg->msg_flags&MSG_OOB)
+ if (msg->msg_flags & MSG_OOB) {
+ err = -EOPNOTSUPP;
goto out;
+ }
if (msg->msg_namelen) {
- err = unix_validate_addr(sunaddr, msg->msg_namelen);
+ err = unix_validate_addr(msg->msg_name, msg->msg_namelen);
if (err)
goto out;
@@ -1998,25 +2128,18 @@ static int unix_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
NULL);
if (err)
goto out;
- } else {
- sunaddr = NULL;
- err = -ENOTCONN;
- other = unix_peer_get(sk);
- if (!other)
- goto out;
}
- if ((test_bit(SOCK_PASSCRED, &sock->flags) ||
- test_bit(SOCK_PASSPIDFD, &sock->flags)) &&
- !READ_ONCE(u->addr)) {
+ if (unix_may_passcred(sk) && !READ_ONCE(u->addr)) {
err = unix_autobind(sk);
if (err)
goto out;
}
- err = -EMSGSIZE;
- if (len > READ_ONCE(sk->sk_sndbuf) - 32)
+ if (len > READ_ONCE(sk->sk_sndbuf) - 32) {
+ err = -EMSGSIZE;
goto out;
+ }
if (len > SKB_MAX_ALLOC) {
data_len = min_t(size_t,
@@ -2030,7 +2153,7 @@ static int unix_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
skb = sock_alloc_send_pskb(sk, len - data_len, data_len,
msg->msg_flags & MSG_DONTWAIT, &err,
PAGE_ALLOC_COSTLY_ORDER);
- if (skb == NULL)
+ if (!skb)
goto out;
err = unix_scm_to_skb(&scm, skb, true);
@@ -2046,17 +2169,18 @@ static int unix_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
-restart:
- if (!other) {
- err = -ECONNRESET;
- if (sunaddr == NULL)
- goto out_free;
-
- other = unix_find_other(sock_net(sk), sunaddr, msg->msg_namelen,
- sk->sk_type);
+ if (msg->msg_namelen) {
+lookup:
+ other = unix_find_other(sock_net(sk), msg->msg_name,
+ msg->msg_namelen, sk->sk_type, 0);
if (IS_ERR(other)) {
err = PTR_ERR(other);
- other = NULL;
+ goto out_free;
+ }
+ } else {
+ other = unix_peer_get(sk);
+ if (!other) {
+ err = -ENOTCONN;
goto out_free;
}
}
@@ -2064,36 +2188,41 @@ restart:
if (sk_filter(other, skb) < 0) {
/* Toss the packet but do not return any error to the sender */
err = len;
- goto out_free;
+ goto out_sock_put;
}
+ err = unix_maybe_add_creds(skb, sk, other);
+ if (err)
+ goto out_sock_put;
+
+restart:
sk_locked = 0;
unix_state_lock(other);
restart_locked:
- err = -EPERM;
- if (!unix_may_send(sk, other))
+
+ if (!unix_may_send(sk, other)) {
+ err = -EPERM;
goto out_unlock;
+ }
if (unlikely(sock_flag(other, SOCK_DEAD))) {
- /*
- * Check with 1003.1g - what should
- * datagram error
- */
- unix_state_unlock(other);
- sock_put(other);
+ /* Check with 1003.1g - what should datagram error */
- if (!sk_locked)
- unix_state_lock(sk);
+ unix_state_unlock(other);
- err = 0;
if (sk->sk_type == SOCK_SEQPACKET) {
/* We are here only when racing with unix_release_sock()
* is clearing @other. Never change state to TCP_CLOSE
* unlike SOCK_DGRAM wants.
*/
- unix_state_unlock(sk);
err = -EPIPE;
- } else if (unix_peer(sk) == other) {
+ goto out_sock_put;
+ }
+
+ if (!sk_locked)
+ unix_state_lock(sk);
+
+ if (unix_peer(sk) == other) {
unix_peer(sk) = NULL;
unix_dgram_peer_wake_disconnect_wakeup(sk, other);
@@ -2103,19 +2232,29 @@ restart_locked:
unix_dgram_disconnected(sk, other);
sock_put(other);
err = -ECONNREFUSED;
- } else {
- unix_state_unlock(sk);
+ goto out_sock_put;
}
- other = NULL;
- if (err)
- goto out_free;
- goto restart;
+ unix_state_unlock(sk);
+
+ if (!msg->msg_namelen) {
+ err = -ECONNRESET;
+ goto out_sock_put;
+ }
+
+ sock_put(other);
+ goto lookup;
}
- err = -EPIPE;
- if (other->sk_shutdown & RCV_SHUTDOWN)
+ if (other->sk_shutdown & RCV_SHUTDOWN) {
+ err = -EPIPE;
goto out_unlock;
+ }
+
+ if (UNIXCB(skb).fp && !other->sk_scm_rights) {
+ err = -EPERM;
+ goto out_unlock;
+ }
if (sk->sk_type != SOCK_SEQPACKET) {
err = security_unix_may_send(sk->sk_socket, other->sk_socket);
@@ -2135,7 +2274,7 @@ restart_locked:
err = sock_intr_errno(timeo);
if (signal_pending(current))
- goto out_free;
+ goto out_sock_put;
goto restart;
}
@@ -2163,7 +2302,7 @@ restart_locked:
if (sock_flag(other, SOCK_RCVTSTAMP))
__net_timestamp(skb);
- maybe_add_creds(skb, sock, other);
+
scm_stat_add(other, skb);
skb_queue_tail(&other->sk_receive_queue, skb);
unix_state_unlock(other);
@@ -2176,11 +2315,11 @@ out_unlock:
if (sk_locked)
unix_state_unlock(sk);
unix_state_unlock(other);
+out_sock_put:
+ sock_put(other);
out_free:
- kfree_skb(skb);
+ consume_skb(skb);
out:
- if (other)
- sock_put(other);
scm_destroy(&scm);
return err;
}
@@ -2191,49 +2330,50 @@ 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,
+static int queue_oob(struct sock *sk, struct msghdr *msg, struct sock *other,
struct scm_cookie *scm, bool fds_sent)
{
struct unix_sock *ousk = unix_sk(other);
struct sk_buff *skb;
- int err = 0;
+ int err;
- skb = sock_alloc_send_skb(sock->sk, 1, msg->msg_flags & MSG_DONTWAIT, &err);
+ skb = sock_alloc_send_skb(sk, 1, msg->msg_flags & MSG_DONTWAIT, &err);
if (!skb)
return err;
err = unix_scm_to_skb(scm, skb, !fds_sent);
- if (err < 0) {
- kfree_skb(skb);
- return err;
- }
+ if (err < 0)
+ goto out;
+
+ err = unix_maybe_add_creds(skb, sk, other);
+ if (err)
+ goto out;
+
skb_put(skb, 1);
err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, 1);
- if (err) {
- kfree_skb(skb);
- return err;
- }
+ if (err)
+ goto out;
unix_state_lock(other);
if (sock_flag(other, SOCK_DEAD) ||
(other->sk_shutdown & RCV_SHUTDOWN)) {
- unix_state_unlock(other);
- kfree_skb(skb);
- return -EPIPE;
+ err = -EPIPE;
+ goto out_unlock;
}
- maybe_add_creds(skb, sock, other);
- skb_get(skb);
+ if (UNIXCB(skb).fp && !other->sk_scm_rights) {
+ err = -EPERM;
+ goto out_unlock;
+ }
scm_stat_add(other, skb);
spin_lock(&other->sk_receive_queue.lock);
- if (ousk->oob_skb)
- consume_skb(ousk->oob_skb);
WRITE_ONCE(ousk->oob_skb, skb);
+ WRITE_ONCE(ousk->inq_len, ousk->inq_len + 1);
__skb_queue_tail(&other->sk_receive_queue, skb);
spin_unlock(&other->sk_receive_queue.lock);
@@ -2241,6 +2381,11 @@ static int queue_oob(struct socket *sock, struct msghdr *msg, struct sock *other
unix_state_unlock(other);
other->sk_data_ready(other);
+ return 0;
+out_unlock:
+ unix_state_unlock(other);
+out:
+ consume_skb(skb);
return err;
}
#endif
@@ -2249,13 +2394,12 @@ static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg,
size_t len)
{
struct sock *sk = sock->sk;
+ struct sk_buff *skb = NULL;
struct sock *other = NULL;
- int err, size;
- struct sk_buff *skb;
- int sent = 0;
+ struct unix_sock *otheru;
struct scm_cookie scm;
bool fds_sent = false;
- int data_len;
+ int err, sent = 0;
err = scm_send(sock, msg, &scm, false);
if (err < 0)
@@ -2263,8 +2407,8 @@ static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg,
wait_for_unix_gc(scm.fp);
- err = -EOPNOTSUPP;
if (msg->msg_flags & MSG_OOB) {
+ err = -EOPNOTSUPP;
#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
if (len)
len--;
@@ -2276,18 +2420,22 @@ static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg,
if (msg->msg_namelen) {
err = READ_ONCE(sk->sk_state) == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP;
goto out_err;
- } else {
+ }
+
+ other = unix_peer(sk);
+ if (!other) {
err = -ENOTCONN;
- other = unix_peer(sk);
- if (!other)
- goto out_err;
+ goto out_err;
}
+ otheru = unix_sk(other);
+
if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
- goto pipe_err;
+ goto out_pipe;
while (sent < len) {
- size = len - sent;
+ int size = len - sent;
+ int data_len;
if (unlikely(msg->msg_flags & MSG_SPLICE_PAGES)) {
skb = sock_alloc_send_pskb(sk, 0, 0,
@@ -2313,19 +2461,21 @@ static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg,
/* Only send the fds in the first buffer */
err = unix_scm_to_skb(&scm, skb, !fds_sent);
- if (err < 0) {
- kfree_skb(skb);
- goto out_err;
- }
+ if (err < 0)
+ goto out_free;
+
fds_sent = true;
+ err = unix_maybe_add_creds(skb, sk, other);
+ if (err)
+ goto out_free;
+
if (unlikely(msg->msg_flags & MSG_SPLICE_PAGES)) {
- err = skb_splice_from_iter(skb, &msg->msg_iter, size,
- sk->sk_allocation);
- if (err < 0) {
- kfree_skb(skb);
- goto out_err;
- }
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ err = skb_splice_from_iter(skb, &msg->msg_iter, size);
+ if (err < 0)
+ goto out_free;
+
size = err;
refcount_add(size, &sk->sk_wmem_alloc);
} else {
@@ -2333,21 +2483,29 @@ static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg,
skb->data_len = data_len;
skb->len = size;
err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, size);
- if (err) {
- kfree_skb(skb);
- goto out_err;
- }
+ if (err)
+ goto out_free;
}
unix_state_lock(other);
if (sock_flag(other, SOCK_DEAD) ||
(other->sk_shutdown & RCV_SHUTDOWN))
- goto pipe_err_free;
+ goto out_pipe_unlock;
+
+ if (UNIXCB(skb).fp && !other->sk_scm_rights) {
+ unix_state_unlock(other);
+ err = -EPERM;
+ goto out_free;
+ }
- maybe_add_creds(skb, sock, other);
scm_stat_add(other, skb);
- skb_queue_tail(&other->sk_receive_queue, skb);
+
+ spin_lock(&other->sk_receive_queue.lock);
+ WRITE_ONCE(otheru->inq_len, otheru->inq_len + skb->len);
+ __skb_queue_tail(&other->sk_receive_queue, skb);
+ spin_unlock(&other->sk_receive_queue.lock);
+
unix_state_unlock(other);
other->sk_data_ready(other);
sent += size;
@@ -2355,7 +2513,7 @@ static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg,
#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
if (msg->msg_flags & MSG_OOB) {
- err = queue_oob(sock, msg, other, &scm, fds_sent);
+ err = queue_oob(sk, msg, other, &scm, fds_sent);
if (err)
goto out_err;
sent++;
@@ -2366,13 +2524,14 @@ static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg,
return sent;
-pipe_err_free:
+out_pipe_unlock:
unix_state_unlock(other);
- kfree_skb(skb);
-pipe_err:
- if (sent == 0 && !(msg->msg_flags&MSG_NOSIGNAL))
+out_pipe:
+ if (!sent && !(msg->msg_flags & MSG_NOSIGNAL))
send_sig(SIGPIPE, current, 0);
err = -EPIPE;
+out_free:
+ consume_skb(skb);
out_err:
scm_destroy(&scm);
return sent ? : err;
@@ -2456,12 +2615,10 @@ int __unix_dgram_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
&err, &timeo, last));
if (!skb) { /* implies iolock unlocked */
- unix_state_lock(sk);
/* Signal EOF on disconnected non-blocking SEQPACKET socket. */
if (sk->sk_type == SOCK_SEQPACKET && err == -EAGAIN &&
- (sk->sk_shutdown & RCV_SHUTDOWN))
+ (READ_ONCE(sk->sk_shutdown) & RCV_SHUTDOWN))
err = 0;
- unix_state_unlock(sk);
goto out;
}
@@ -2492,8 +2649,7 @@ int __unix_dgram_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
memset(&scm, 0, sizeof(scm));
- scm_set_cred(&scm, UNIXCB(skb).pid, UNIXCB(skb).uid, UNIXCB(skb).gid);
- unix_set_secdata(&scm, skb);
+ unix_skb_to_scm(skb, &scm);
if (!(flags & MSG_PEEK)) {
if (UNIXCB(skb).fp)
@@ -2600,11 +2756,6 @@ static long unix_stream_data_wait(struct sock *sk, long timeo,
return timeo;
}
-static unsigned int unix_skb_len(const struct sk_buff *skb)
-{
- return skb->len - UNIXCB(skb).consumed;
-}
-
struct unix_stream_read_state {
int (*recv_actor)(struct sk_buff *, int, int,
struct unix_stream_read_state *);
@@ -2619,11 +2770,11 @@ struct unix_stream_read_state {
#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
static int unix_stream_recv_urg(struct unix_stream_read_state *state)
{
+ struct sk_buff *oob_skb, *read_skb = NULL;
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);
@@ -2638,10 +2789,16 @@ static int unix_stream_recv_urg(struct unix_stream_read_state *state)
oob_skb = u->oob_skb;
- if (!(state->flags & MSG_PEEK))
+ if (!(state->flags & MSG_PEEK)) {
WRITE_ONCE(u->oob_skb, NULL);
- else
- skb_get(oob_skb);
+ WRITE_ONCE(u->inq_len, u->inq_len - 1);
+
+ if (oob_skb->prev != (struct sk_buff *)&sk->sk_receive_queue &&
+ !unix_skb_len(oob_skb->prev)) {
+ read_skb = oob_skb->prev;
+ __skb_unlink(read_skb, &sk->sk_receive_queue);
+ }
+ }
spin_unlock(&sk->sk_receive_queue.lock);
unix_state_unlock(sk);
@@ -2651,10 +2808,10 @@ static int unix_stream_recv_urg(struct unix_stream_read_state *state)
if (!(state->flags & MSG_PEEK))
UNIXCB(oob_skb).consumed += 1;
- consume_skb(oob_skb);
-
mutex_unlock(&u->iolock);
+ consume_skb(read_skb);
+
if (chunk < 0)
return -EFAULT;
@@ -2665,62 +2822,59 @@ static int unix_stream_recv_urg(struct unix_stream_read_state *state)
static struct sk_buff *manage_oob(struct sk_buff *skb, struct sock *sk,
int flags, int copied)
{
+ struct sk_buff *read_skb = NULL, *unread_skb = NULL;
struct unix_sock *u = unix_sk(sk);
- if (!unix_skb_len(skb)) {
- struct sk_buff *unlinked_skb = NULL;
+ if (likely(unix_skb_len(skb) && skb != READ_ONCE(u->oob_skb)))
+ return skb;
- spin_lock(&sk->sk_receive_queue.lock);
+ spin_lock(&sk->sk_receive_queue.lock);
+ if (!unix_skb_len(skb)) {
if (copied && (!u->oob_skb || skb == u->oob_skb)) {
skb = NULL;
} else if (flags & MSG_PEEK) {
skb = skb_peek_next(skb, &sk->sk_receive_queue);
} else {
- unlinked_skb = skb;
+ read_skb = skb;
skb = skb_peek_next(skb, &sk->sk_receive_queue);
- __skb_unlink(unlinked_skb, &sk->sk_receive_queue);
+ __skb_unlink(read_skb, &sk->sk_receive_queue);
}
- spin_unlock(&sk->sk_receive_queue.lock);
+ if (!skb)
+ goto unlock;
+ }
- consume_skb(unlinked_skb);
- } else {
- struct sk_buff *unlinked_skb = NULL;
-
- spin_lock(&sk->sk_receive_queue.lock);
-
- if (skb == u->oob_skb) {
- if (copied) {
- skb = NULL;
- } else if (!(flags & MSG_PEEK)) {
- if (sock_flag(sk, SOCK_URGINLINE)) {
- WRITE_ONCE(u->oob_skb, NULL);
- consume_skb(skb);
- } else {
- __skb_unlink(skb, &sk->sk_receive_queue);
- WRITE_ONCE(u->oob_skb, NULL);
- unlinked_skb = skb;
- skb = skb_peek(&sk->sk_receive_queue);
- }
- } else if (!sock_flag(sk, SOCK_URGINLINE)) {
- skb = skb_peek_next(skb, &sk->sk_receive_queue);
- }
- }
+ if (skb != u->oob_skb)
+ goto unlock;
- spin_unlock(&sk->sk_receive_queue.lock);
+ if (copied) {
+ skb = NULL;
+ } else if (!(flags & MSG_PEEK)) {
+ WRITE_ONCE(u->oob_skb, NULL);
- if (unlinked_skb) {
- WARN_ON_ONCE(skb_unref(unlinked_skb));
- kfree_skb(unlinked_skb);
+ if (!sock_flag(sk, SOCK_URGINLINE)) {
+ __skb_unlink(skb, &sk->sk_receive_queue);
+ unread_skb = skb;
+ skb = skb_peek(&sk->sk_receive_queue);
}
+ } else if (!sock_flag(sk, SOCK_URGINLINE)) {
+ skb = skb_peek_next(skb, &sk->sk_receive_queue);
}
+
+unlock:
+ spin_unlock(&sk->sk_receive_queue.lock);
+
+ consume_skb(read_skb);
+ kfree_skb_reason(unread_skb, SKB_DROP_REASON_UNIX_SKIP_OOB);
+
return skb;
}
#endif
static int unix_stream_read_skb(struct sock *sk, skb_read_actor_t recv_actor)
{
+ struct sk_buff_head *queue = &sk->sk_receive_queue;
struct unix_sock *u = unix_sk(sk);
struct sk_buff *skb;
int err;
@@ -2728,61 +2882,57 @@ static int unix_stream_read_skb(struct sock *sk, skb_read_actor_t recv_actor)
if (unlikely(READ_ONCE(sk->sk_state) != TCP_ESTABLISHED))
return -ENOTCONN;
- mutex_lock(&u->iolock);
- skb = skb_recv_datagram(sk, MSG_DONTWAIT, &err);
- mutex_unlock(&u->iolock);
- if (!skb)
+ err = sock_error(sk);
+ if (err)
return err;
-#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
- if (unlikely(skb == READ_ONCE(u->oob_skb))) {
- bool drop = false;
-
- unix_state_lock(sk);
+ mutex_lock(&u->iolock);
+ spin_lock(&queue->lock);
- if (sock_flag(sk, SOCK_DEAD)) {
- unix_state_unlock(sk);
- kfree_skb(skb);
- return -ECONNRESET;
- }
+ skb = __skb_dequeue(queue);
+ if (!skb) {
+ spin_unlock(&queue->lock);
+ mutex_unlock(&u->iolock);
+ return -EAGAIN;
+ }
- spin_lock(&sk->sk_receive_queue.lock);
- if (likely(skb == u->oob_skb)) {
- WRITE_ONCE(u->oob_skb, NULL);
- drop = true;
- }
- spin_unlock(&sk->sk_receive_queue.lock);
+ WRITE_ONCE(u->inq_len, u->inq_len - skb->len);
- unix_state_unlock(sk);
+#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
+ if (skb == u->oob_skb) {
+ WRITE_ONCE(u->oob_skb, NULL);
+ spin_unlock(&queue->lock);
+ mutex_unlock(&u->iolock);
- if (drop) {
- WARN_ON_ONCE(skb_unref(skb));
- kfree_skb(skb);
- return -EAGAIN;
- }
+ kfree_skb_reason(skb, SKB_DROP_REASON_UNIX_SKIP_OOB);
+ return -EAGAIN;
}
#endif
+ spin_unlock(&queue->lock);
+ mutex_unlock(&u->iolock);
+
return recv_actor(sk, skb);
}
static int unix_stream_read_generic(struct unix_stream_read_state *state,
bool freezable)
{
- struct scm_cookie scm;
+ int noblock = state->flags & MSG_DONTWAIT;
struct socket *sock = state->socket;
+ struct msghdr *msg = state->msg;
struct sock *sk = sock->sk;
- struct unix_sock *u = unix_sk(sk);
- int copied = 0;
+ size_t size = state->size;
int flags = state->flags;
- int noblock = flags & MSG_DONTWAIT;
bool check_creds = false;
- int target;
+ struct scm_cookie scm;
+ unsigned int last_len;
+ struct unix_sock *u;
+ int copied = 0;
int err = 0;
long timeo;
+ int target;
int skip;
- size_t size = state->size;
- unsigned int last_len;
if (unlikely(READ_ONCE(sk->sk_state) != TCP_ESTABLISHED)) {
err = -EINVAL;
@@ -2802,6 +2952,8 @@ static int unix_stream_read_generic(struct unix_stream_read_state *state,
memset(&scm, 0, sizeof(scm));
+ u = unix_sk(sk);
+
/* Lock the socket to prevent queue disordering
* while sleeps in memcpy_tomsg
*/
@@ -2885,23 +3037,19 @@ unlock:
/* Never glue messages from different writers */
if (!unix_skb_scm_eq(skb, &scm))
break;
- } else if (test_bit(SOCK_PASSCRED, &sock->flags) ||
- test_bit(SOCK_PASSPIDFD, &sock->flags)) {
+ } else if (unix_may_passcred(sk)) {
/* Copy credentials */
- scm_set_cred(&scm, UNIXCB(skb).pid, UNIXCB(skb).uid, UNIXCB(skb).gid);
- unix_set_secdata(&scm, skb);
+ unix_skb_to_scm(skb, &scm);
check_creds = true;
}
/* Copy address just once */
- if (state->msg && state->msg->msg_name) {
- DECLARE_SOCKADDR(struct sockaddr_un *, sunaddr,
- state->msg->msg_name);
- unix_copy_addr(state->msg, skb->sk);
+ if (msg && msg->msg_name) {
+ DECLARE_SOCKADDR(struct sockaddr_un *, sunaddr, msg->msg_name);
- BPF_CGROUP_RUN_PROG_UNIX_RECVMSG_LOCK(sk,
- state->msg->msg_name,
- &state->msg->msg_namelen);
+ unix_copy_addr(msg, skb->sk);
+ BPF_CGROUP_RUN_PROG_UNIX_RECVMSG_LOCK(sk, msg->msg_name,
+ &msg->msg_namelen);
sunaddr = NULL;
}
@@ -2930,7 +3078,11 @@ unlock:
if (unix_skb_len(skb))
break;
- skb_unlink(skb, &sk->sk_receive_queue);
+ spin_lock(&sk->sk_receive_queue.lock);
+ WRITE_ONCE(u->inq_len, u->inq_len - skb->len);
+ __skb_unlink(skb, &sk->sk_receive_queue);
+ spin_unlock(&sk->sk_receive_queue.lock);
+
consume_skb(skb);
if (scm.fp)
@@ -2959,10 +3111,17 @@ unlock:
} while (size);
mutex_unlock(&u->iolock);
- if (state->msg)
- scm_recv_unix(sock, state->msg, &scm, flags);
- else
+ if (msg) {
+ scm_recv_unix(sock, msg, &scm, flags);
+
+ if (READ_ONCE(u->recvmsg_inq) || msg->msg_get_inq) {
+ msg->msg_inq = READ_ONCE(u->inq_len);
+ put_cmsg(msg, SOL_SOCKET, SCM_INQ,
+ sizeof(msg->msg_inq), &msg->msg_inq);
+ }
+ } else {
scm_destroy(&scm);
+ }
out:
return copied ? : err;
}
@@ -3101,9 +3260,11 @@ long unix_inq_len(struct sock *sk)
if (READ_ONCE(sk->sk_state) == TCP_LISTEN)
return -EINVAL;
+ if (sk->sk_type == SOCK_STREAM)
+ return READ_ONCE(unix_sk(sk)->inq_len);
+
spin_lock(&sk->sk_receive_queue.lock);
- if (sk->sk_type == SOCK_STREAM ||
- sk->sk_type == SOCK_SEQPACKET) {
+ if (sk->sk_type == SOCK_SEQPACKET) {
skb_queue_walk(&sk->sk_receive_queue, skb)
amount += unix_skb_len(skb);
} else {
@@ -3125,7 +3286,6 @@ EXPORT_SYMBOL_GPL(unix_outq_len);
static int unix_open_file(struct sock *sk)
{
- struct path path;
struct file *f;
int fd;
@@ -3135,27 +3295,20 @@ static int unix_open_file(struct sock *sk)
if (!smp_load_acquire(&unix_sk(sk)->addr))
return -ENOENT;
- path = unix_sk(sk)->path;
- if (!path.dentry)
+ if (!unix_sk(sk)->path.dentry)
return -ENOENT;
- path_get(&path);
-
fd = get_unused_fd_flags(O_CLOEXEC);
if (fd < 0)
- goto out;
+ return fd;
- f = dentry_open(&path, O_PATH, current_cred());
+ f = dentry_open(&unix_sk(sk)->path, O_PATH, current_cred());
if (IS_ERR(f)) {
put_unused_fd(fd);
- fd = PTR_ERR(f);
- goto out;
+ return PTR_ERR(f);
}
fd_install(fd, f);
-out:
- path_put(&path);
-
return fd;
}
@@ -3192,9 +3345,13 @@ static int unix_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
skb = skb_peek(&sk->sk_receive_queue);
if (skb) {
struct sk_buff *oob_skb = READ_ONCE(u->oob_skb);
+ struct sk_buff *next_skb;
+
+ next_skb = skb_peek_next(skb, &sk->sk_receive_queue);
if (skb == oob_skb ||
- (!oob_skb && !unix_skb_len(skb)))
+ (!unix_skb_len(skb) &&
+ (!oob_skb || next_skb == oob_skb)))
answ = 1;
}
@@ -3627,7 +3784,7 @@ static int bpf_iter_unix_seq_show(struct seq_file *seq, void *v)
goto unlock;
}
- uid = from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk));
+ uid = from_kuid_munged(seq_user_ns(seq), sk_uid(sk));
meta.seq = seq;
prog = bpf_iter_get_info(&meta, false);
ret = unix_prog_seq_show(prog, &meta, v, uid);
generated by cgit v1.2.3 (git 2.46.0) at 2025-12-12 15:45:16 +0000