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-rw-r--r--net/socket.c3693
1 files changed, 3693 insertions, 0 deletions
diff --git a/net/socket.c b/net/socket.c
new file mode 100644
index 000000000..639d76f20
--- /dev/null
+++ b/net/socket.c
@@ -0,0 +1,3693 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * NET An implementation of the SOCKET network access protocol.
+ *
+ * Version: @(#)socket.c 1.1.93 18/02/95
+ *
+ * Authors: Orest Zborowski, <obz@Kodak.COM>
+ * Ross Biro
+ * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
+ *
+ * Fixes:
+ * Anonymous : NOTSOCK/BADF cleanup. Error fix in
+ * shutdown()
+ * Alan Cox : verify_area() fixes
+ * Alan Cox : Removed DDI
+ * Jonathan Kamens : SOCK_DGRAM reconnect bug
+ * Alan Cox : Moved a load of checks to the very
+ * top level.
+ * Alan Cox : Move address structures to/from user
+ * mode above the protocol layers.
+ * Rob Janssen : Allow 0 length sends.
+ * Alan Cox : Asynchronous I/O support (cribbed from the
+ * tty drivers).
+ * Niibe Yutaka : Asynchronous I/O for writes (4.4BSD style)
+ * Jeff Uphoff : Made max number of sockets command-line
+ * configurable.
+ * Matti Aarnio : Made the number of sockets dynamic,
+ * to be allocated when needed, and mr.
+ * Uphoff's max is used as max to be
+ * allowed to allocate.
+ * Linus : Argh. removed all the socket allocation
+ * altogether: it's in the inode now.
+ * Alan Cox : Made sock_alloc()/sock_release() public
+ * for NetROM and future kernel nfsd type
+ * stuff.
+ * Alan Cox : sendmsg/recvmsg basics.
+ * Tom Dyas : Export net symbols.
+ * Marcin Dalecki : Fixed problems with CONFIG_NET="n".
+ * Alan Cox : Added thread locking to sys_* calls
+ * for sockets. May have errors at the
+ * moment.
+ * Kevin Buhr : Fixed the dumb errors in the above.
+ * Andi Kleen : Some small cleanups, optimizations,
+ * and fixed a copy_from_user() bug.
+ * Tigran Aivazian : sys_send(args) calls sys_sendto(args, NULL, 0)
+ * Tigran Aivazian : Made listen(2) backlog sanity checks
+ * protocol-independent
+ *
+ * This module is effectively the top level interface to the BSD socket
+ * paradigm.
+ *
+ * Based upon Swansea University Computer Society NET3.039
+ */
+
+#include <linux/bpf-cgroup.h>
+#include <linux/ethtool.h>
+#include <linux/mm.h>
+#include <linux/socket.h>
+#include <linux/file.h>
+#include <linux/net.h>
+#include <linux/interrupt.h>
+#include <linux/thread_info.h>
+#include <linux/rcupdate.h>
+#include <linux/netdevice.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/mutex.h>
+#include <linux/if_bridge.h>
+#include <linux/if_vlan.h>
+#include <linux/ptp_classify.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <linux/cache.h>
+#include <linux/module.h>
+#include <linux/highmem.h>
+#include <linux/mount.h>
+#include <linux/pseudo_fs.h>
+#include <linux/security.h>
+#include <linux/syscalls.h>
+#include <linux/compat.h>
+#include <linux/kmod.h>
+#include <linux/audit.h>
+#include <linux/wireless.h>
+#include <linux/nsproxy.h>
+#include <linux/magic.h>
+#include <linux/slab.h>
+#include <linux/xattr.h>
+#include <linux/nospec.h>
+#include <linux/indirect_call_wrapper.h>
+
+#include <linux/uaccess.h>
+#include <asm/unistd.h>
+
+#include <net/compat.h>
+#include <net/wext.h>
+#include <net/cls_cgroup.h>
+
+#include <net/sock.h>
+#include <linux/netfilter.h>
+
+#include <linux/if_tun.h>
+#include <linux/ipv6_route.h>
+#include <linux/route.h>
+#include <linux/termios.h>
+#include <linux/sockios.h>
+#include <net/busy_poll.h>
+#include <linux/errqueue.h>
+#include <linux/ptp_clock_kernel.h>
+
+#ifdef CONFIG_NET_RX_BUSY_POLL
+unsigned int sysctl_net_busy_read __read_mostly;
+unsigned int sysctl_net_busy_poll __read_mostly;
+#endif
+
+static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to);
+static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from);
+static int sock_mmap(struct file *file, struct vm_area_struct *vma);
+
+static int sock_close(struct inode *inode, struct file *file);
+static __poll_t sock_poll(struct file *file,
+ struct poll_table_struct *wait);
+static long sock_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+#ifdef CONFIG_COMPAT
+static long compat_sock_ioctl(struct file *file,
+ unsigned int cmd, unsigned long arg);
+#endif
+static int sock_fasync(int fd, struct file *filp, int on);
+static ssize_t sock_sendpage(struct file *file, struct page *page,
+ int offset, size_t size, loff_t *ppos, int more);
+static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
+ struct pipe_inode_info *pipe, size_t len,
+ unsigned int flags);
+static void sock_splice_eof(struct file *file);
+
+#ifdef CONFIG_PROC_FS
+static void sock_show_fdinfo(struct seq_file *m, struct file *f)
+{
+ struct socket *sock = f->private_data;
+
+ if (sock->ops->show_fdinfo)
+ sock->ops->show_fdinfo(m, sock);
+}
+#else
+#define sock_show_fdinfo NULL
+#endif
+
+/*
+ * Socket files have a set of 'special' operations as well as the generic file ones. These don't appear
+ * in the operation structures but are done directly via the socketcall() multiplexor.
+ */
+
+static const struct file_operations socket_file_ops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .read_iter = sock_read_iter,
+ .write_iter = sock_write_iter,
+ .poll = sock_poll,
+ .unlocked_ioctl = sock_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = compat_sock_ioctl,
+#endif
+ .mmap = sock_mmap,
+ .release = sock_close,
+ .fasync = sock_fasync,
+ .sendpage = sock_sendpage,
+ .splice_write = generic_splice_sendpage,
+ .splice_read = sock_splice_read,
+ .splice_eof = sock_splice_eof,
+ .show_fdinfo = sock_show_fdinfo,
+};
+
+static const char * const pf_family_names[] = {
+ [PF_UNSPEC] = "PF_UNSPEC",
+ [PF_UNIX] = "PF_UNIX/PF_LOCAL",
+ [PF_INET] = "PF_INET",
+ [PF_AX25] = "PF_AX25",
+ [PF_IPX] = "PF_IPX",
+ [PF_APPLETALK] = "PF_APPLETALK",
+ [PF_NETROM] = "PF_NETROM",
+ [PF_BRIDGE] = "PF_BRIDGE",
+ [PF_ATMPVC] = "PF_ATMPVC",
+ [PF_X25] = "PF_X25",
+ [PF_INET6] = "PF_INET6",
+ [PF_ROSE] = "PF_ROSE",
+ [PF_DECnet] = "PF_DECnet",
+ [PF_NETBEUI] = "PF_NETBEUI",
+ [PF_SECURITY] = "PF_SECURITY",
+ [PF_KEY] = "PF_KEY",
+ [PF_NETLINK] = "PF_NETLINK/PF_ROUTE",
+ [PF_PACKET] = "PF_PACKET",
+ [PF_ASH] = "PF_ASH",
+ [PF_ECONET] = "PF_ECONET",
+ [PF_ATMSVC] = "PF_ATMSVC",
+ [PF_RDS] = "PF_RDS",
+ [PF_SNA] = "PF_SNA",
+ [PF_IRDA] = "PF_IRDA",
+ [PF_PPPOX] = "PF_PPPOX",
+ [PF_WANPIPE] = "PF_WANPIPE",
+ [PF_LLC] = "PF_LLC",
+ [PF_IB] = "PF_IB",
+ [PF_MPLS] = "PF_MPLS",
+ [PF_CAN] = "PF_CAN",
+ [PF_TIPC] = "PF_TIPC",
+ [PF_BLUETOOTH] = "PF_BLUETOOTH",
+ [PF_IUCV] = "PF_IUCV",
+ [PF_RXRPC] = "PF_RXRPC",
+ [PF_ISDN] = "PF_ISDN",
+ [PF_PHONET] = "PF_PHONET",
+ [PF_IEEE802154] = "PF_IEEE802154",
+ [PF_CAIF] = "PF_CAIF",
+ [PF_ALG] = "PF_ALG",
+ [PF_NFC] = "PF_NFC",
+ [PF_VSOCK] = "PF_VSOCK",
+ [PF_KCM] = "PF_KCM",
+ [PF_QIPCRTR] = "PF_QIPCRTR",
+ [PF_SMC] = "PF_SMC",
+ [PF_XDP] = "PF_XDP",
+ [PF_MCTP] = "PF_MCTP",
+};
+
+/*
+ * The protocol list. Each protocol is registered in here.
+ */
+
+static DEFINE_SPINLOCK(net_family_lock);
+static const struct net_proto_family __rcu *net_families[NPROTO] __read_mostly;
+
+/*
+ * Support routines.
+ * Move socket addresses back and forth across the kernel/user
+ * divide and look after the messy bits.
+ */
+
+/**
+ * move_addr_to_kernel - copy a socket address into kernel space
+ * @uaddr: Address in user space
+ * @kaddr: Address in kernel space
+ * @ulen: Length in user space
+ *
+ * The address is copied into kernel space. If the provided address is
+ * too long an error code of -EINVAL is returned. If the copy gives
+ * invalid addresses -EFAULT is returned. On a success 0 is returned.
+ */
+
+int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr_storage *kaddr)
+{
+ if (ulen < 0 || ulen > sizeof(struct sockaddr_storage))
+ return -EINVAL;
+ if (ulen == 0)
+ return 0;
+ if (copy_from_user(kaddr, uaddr, ulen))
+ return -EFAULT;
+ return audit_sockaddr(ulen, kaddr);
+}
+
+/**
+ * move_addr_to_user - copy an address to user space
+ * @kaddr: kernel space address
+ * @klen: length of address in kernel
+ * @uaddr: user space address
+ * @ulen: pointer to user length field
+ *
+ * The value pointed to by ulen on entry is the buffer length available.
+ * This is overwritten with the buffer space used. -EINVAL is returned
+ * if an overlong buffer is specified or a negative buffer size. -EFAULT
+ * is returned if either the buffer or the length field are not
+ * accessible.
+ * After copying the data up to the limit the user specifies, the true
+ * length of the data is written over the length limit the user
+ * specified. Zero is returned for a success.
+ */
+
+static int move_addr_to_user(struct sockaddr_storage *kaddr, int klen,
+ void __user *uaddr, int __user *ulen)
+{
+ int err;
+ int len;
+
+ BUG_ON(klen > sizeof(struct sockaddr_storage));
+ err = get_user(len, ulen);
+ if (err)
+ return err;
+ if (len > klen)
+ len = klen;
+ if (len < 0)
+ return -EINVAL;
+ if (len) {
+ if (audit_sockaddr(klen, kaddr))
+ return -ENOMEM;
+ if (copy_to_user(uaddr, kaddr, len))
+ return -EFAULT;
+ }
+ /*
+ * "fromlen shall refer to the value before truncation.."
+ * 1003.1g
+ */
+ return __put_user(klen, ulen);
+}
+
+static struct kmem_cache *sock_inode_cachep __ro_after_init;
+
+static struct inode *sock_alloc_inode(struct super_block *sb)
+{
+ struct socket_alloc *ei;
+
+ ei = alloc_inode_sb(sb, sock_inode_cachep, GFP_KERNEL);
+ if (!ei)
+ return NULL;
+ init_waitqueue_head(&ei->socket.wq.wait);
+ ei->socket.wq.fasync_list = NULL;
+ ei->socket.wq.flags = 0;
+
+ ei->socket.state = SS_UNCONNECTED;
+ ei->socket.flags = 0;
+ ei->socket.ops = NULL;
+ ei->socket.sk = NULL;
+ ei->socket.file = NULL;
+
+ return &ei->vfs_inode;
+}
+
+static void sock_free_inode(struct inode *inode)
+{
+ struct socket_alloc *ei;
+
+ ei = container_of(inode, struct socket_alloc, vfs_inode);
+ kmem_cache_free(sock_inode_cachep, ei);
+}
+
+static void init_once(void *foo)
+{
+ struct socket_alloc *ei = (struct socket_alloc *)foo;
+
+ inode_init_once(&ei->vfs_inode);
+}
+
+static void init_inodecache(void)
+{
+ sock_inode_cachep = kmem_cache_create("sock_inode_cache",
+ sizeof(struct socket_alloc),
+ 0,
+ (SLAB_HWCACHE_ALIGN |
+ SLAB_RECLAIM_ACCOUNT |
+ SLAB_MEM_SPREAD | SLAB_ACCOUNT),
+ init_once);
+ BUG_ON(sock_inode_cachep == NULL);
+}
+
+static const struct super_operations sockfs_ops = {
+ .alloc_inode = sock_alloc_inode,
+ .free_inode = sock_free_inode,
+ .statfs = simple_statfs,
+};
+
+/*
+ * sockfs_dname() is called from d_path().
+ */
+static char *sockfs_dname(struct dentry *dentry, char *buffer, int buflen)
+{
+ return dynamic_dname(buffer, buflen, "socket:[%lu]",
+ d_inode(dentry)->i_ino);
+}
+
+static const struct dentry_operations sockfs_dentry_operations = {
+ .d_dname = sockfs_dname,
+};
+
+static int sockfs_xattr_get(const struct xattr_handler *handler,
+ struct dentry *dentry, struct inode *inode,
+ const char *suffix, void *value, size_t size)
+{
+ if (value) {
+ if (dentry->d_name.len + 1 > size)
+ return -ERANGE;
+ memcpy(value, dentry->d_name.name, dentry->d_name.len + 1);
+ }
+ return dentry->d_name.len + 1;
+}
+
+#define XATTR_SOCKPROTONAME_SUFFIX "sockprotoname"
+#define XATTR_NAME_SOCKPROTONAME (XATTR_SYSTEM_PREFIX XATTR_SOCKPROTONAME_SUFFIX)
+#define XATTR_NAME_SOCKPROTONAME_LEN (sizeof(XATTR_NAME_SOCKPROTONAME)-1)
+
+static const struct xattr_handler sockfs_xattr_handler = {
+ .name = XATTR_NAME_SOCKPROTONAME,
+ .get = sockfs_xattr_get,
+};
+
+static int sockfs_security_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *mnt_userns,
+ struct dentry *dentry, struct inode *inode,
+ const char *suffix, const void *value,
+ size_t size, int flags)
+{
+ /* Handled by LSM. */
+ return -EAGAIN;
+}
+
+static const struct xattr_handler sockfs_security_xattr_handler = {
+ .prefix = XATTR_SECURITY_PREFIX,
+ .set = sockfs_security_xattr_set,
+};
+
+static const struct xattr_handler *sockfs_xattr_handlers[] = {
+ &sockfs_xattr_handler,
+ &sockfs_security_xattr_handler,
+ NULL
+};
+
+static int sockfs_init_fs_context(struct fs_context *fc)
+{
+ struct pseudo_fs_context *ctx = init_pseudo(fc, SOCKFS_MAGIC);
+ if (!ctx)
+ return -ENOMEM;
+ ctx->ops = &sockfs_ops;
+ ctx->dops = &sockfs_dentry_operations;
+ ctx->xattr = sockfs_xattr_handlers;
+ return 0;
+}
+
+static struct vfsmount *sock_mnt __read_mostly;
+
+static struct file_system_type sock_fs_type = {
+ .name = "sockfs",
+ .init_fs_context = sockfs_init_fs_context,
+ .kill_sb = kill_anon_super,
+};
+
+/*
+ * Obtains the first available file descriptor and sets it up for use.
+ *
+ * These functions create file structures and maps them to fd space
+ * of the current process. On success it returns file descriptor
+ * and file struct implicitly stored in sock->file.
+ * Note that another thread may close file descriptor before we return
+ * from this function. We use the fact that now we do not refer
+ * to socket after mapping. If one day we will need it, this
+ * function will increment ref. count on file by 1.
+ *
+ * In any case returned fd MAY BE not valid!
+ * This race condition is unavoidable
+ * with shared fd spaces, we cannot solve it inside kernel,
+ * but we take care of internal coherence yet.
+ */
+
+/**
+ * sock_alloc_file - Bind a &socket to a &file
+ * @sock: socket
+ * @flags: file status flags
+ * @dname: protocol name
+ *
+ * Returns the &file bound with @sock, implicitly storing it
+ * in sock->file. If dname is %NULL, sets to "".
+ *
+ * On failure @sock is released, and an ERR pointer is returned.
+ *
+ * This function uses GFP_KERNEL internally.
+ */
+
+struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname)
+{
+ struct file *file;
+
+ if (!dname)
+ dname = sock->sk ? sock->sk->sk_prot_creator->name : "";
+
+ file = alloc_file_pseudo(SOCK_INODE(sock), sock_mnt, dname,
+ O_RDWR | (flags & O_NONBLOCK),
+ &socket_file_ops);
+ if (IS_ERR(file)) {
+ sock_release(sock);
+ return file;
+ }
+
+ sock->file = file;
+ file->private_data = sock;
+ stream_open(SOCK_INODE(sock), file);
+ return file;
+}
+EXPORT_SYMBOL(sock_alloc_file);
+
+static int sock_map_fd(struct socket *sock, int flags)
+{
+ struct file *newfile;
+ int fd = get_unused_fd_flags(flags);
+ if (unlikely(fd < 0)) {
+ sock_release(sock);
+ return fd;
+ }
+
+ newfile = sock_alloc_file(sock, flags, NULL);
+ if (!IS_ERR(newfile)) {
+ fd_install(fd, newfile);
+ return fd;
+ }
+
+ put_unused_fd(fd);
+ return PTR_ERR(newfile);
+}
+
+/**
+ * sock_from_file - Return the &socket bounded to @file.
+ * @file: file
+ *
+ * On failure returns %NULL.
+ */
+
+struct socket *sock_from_file(struct file *file)
+{
+ if (file->f_op == &socket_file_ops)
+ return file->private_data; /* set in sock_alloc_file */
+
+ return NULL;
+}
+EXPORT_SYMBOL(sock_from_file);
+
+/**
+ * sockfd_lookup - Go from a file number to its socket slot
+ * @fd: file handle
+ * @err: pointer to an error code return
+ *
+ * The file handle passed in is locked and the socket it is bound
+ * to is returned. If an error occurs the err pointer is overwritten
+ * with a negative errno code and NULL is returned. The function checks
+ * for both invalid handles and passing a handle which is not a socket.
+ *
+ * On a success the socket object pointer is returned.
+ */
+
+struct socket *sockfd_lookup(int fd, int *err)
+{
+ struct file *file;
+ struct socket *sock;
+
+ file = fget(fd);
+ if (!file) {
+ *err = -EBADF;
+ return NULL;
+ }
+
+ sock = sock_from_file(file);
+ if (!sock) {
+ *err = -ENOTSOCK;
+ fput(file);
+ }
+ return sock;
+}
+EXPORT_SYMBOL(sockfd_lookup);
+
+static struct socket *sockfd_lookup_light(int fd, int *err, int *fput_needed)
+{
+ struct fd f = fdget(fd);
+ struct socket *sock;
+
+ *err = -EBADF;
+ if (f.file) {
+ sock = sock_from_file(f.file);
+ if (likely(sock)) {
+ *fput_needed = f.flags & FDPUT_FPUT;
+ return sock;
+ }
+ *err = -ENOTSOCK;
+ fdput(f);
+ }
+ return NULL;
+}
+
+static ssize_t sockfs_listxattr(struct dentry *dentry, char *buffer,
+ size_t size)
+{
+ ssize_t len;
+ ssize_t used = 0;
+
+ len = security_inode_listsecurity(d_inode(dentry), buffer, size);
+ if (len < 0)
+ return len;
+ used += len;
+ if (buffer) {
+ if (size < used)
+ return -ERANGE;
+ buffer += len;
+ }
+
+ len = (XATTR_NAME_SOCKPROTONAME_LEN + 1);
+ used += len;
+ if (buffer) {
+ if (size < used)
+ return -ERANGE;
+ memcpy(buffer, XATTR_NAME_SOCKPROTONAME, len);
+ buffer += len;
+ }
+
+ return used;
+}
+
+static int sockfs_setattr(struct user_namespace *mnt_userns,
+ struct dentry *dentry, struct iattr *iattr)
+{
+ int err = simple_setattr(&init_user_ns, dentry, iattr);
+
+ if (!err && (iattr->ia_valid & ATTR_UID)) {
+ struct socket *sock = SOCKET_I(d_inode(dentry));
+
+ if (sock->sk)
+ sock->sk->sk_uid = iattr->ia_uid;
+ else
+ err = -ENOENT;
+ }
+
+ return err;
+}
+
+static const struct inode_operations sockfs_inode_ops = {
+ .listxattr = sockfs_listxattr,
+ .setattr = sockfs_setattr,
+};
+
+/**
+ * sock_alloc - allocate a socket
+ *
+ * Allocate a new inode and socket object. The two are bound together
+ * and initialised. The socket is then returned. If we are out of inodes
+ * NULL is returned. This functions uses GFP_KERNEL internally.
+ */
+
+struct socket *sock_alloc(void)
+{
+ struct inode *inode;
+ struct socket *sock;
+
+ inode = new_inode_pseudo(sock_mnt->mnt_sb);
+ if (!inode)
+ return NULL;
+
+ sock = SOCKET_I(inode);
+
+ inode->i_ino = get_next_ino();
+ inode->i_mode = S_IFSOCK | S_IRWXUGO;
+ inode->i_uid = current_fsuid();
+ inode->i_gid = current_fsgid();
+ inode->i_op = &sockfs_inode_ops;
+
+ return sock;
+}
+EXPORT_SYMBOL(sock_alloc);
+
+static void __sock_release(struct socket *sock, struct inode *inode)
+{
+ if (sock->ops) {
+ struct module *owner = sock->ops->owner;
+
+ if (inode)
+ inode_lock(inode);
+ sock->ops->release(sock);
+ sock->sk = NULL;
+ if (inode)
+ inode_unlock(inode);
+ sock->ops = NULL;
+ module_put(owner);
+ }
+
+ if (sock->wq.fasync_list)
+ pr_err("%s: fasync list not empty!\n", __func__);
+
+ if (!sock->file) {
+ iput(SOCK_INODE(sock));
+ return;
+ }
+ sock->file = NULL;
+}
+
+/**
+ * sock_release - close a socket
+ * @sock: socket to close
+ *
+ * The socket is released from the protocol stack if it has a release
+ * callback, and the inode is then released if the socket is bound to
+ * an inode not a file.
+ */
+void sock_release(struct socket *sock)
+{
+ __sock_release(sock, NULL);
+}
+EXPORT_SYMBOL(sock_release);
+
+void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags)
+{
+ u8 flags = *tx_flags;
+
+ if (tsflags & SOF_TIMESTAMPING_TX_HARDWARE) {
+ flags |= SKBTX_HW_TSTAMP;
+
+ /* PTP hardware clocks can provide a free running cycle counter
+ * as a time base for virtual clocks. Tell driver to use the
+ * free running cycle counter for timestamp if socket is bound
+ * to virtual clock.
+ */
+ if (tsflags & SOF_TIMESTAMPING_BIND_PHC)
+ flags |= SKBTX_HW_TSTAMP_USE_CYCLES;
+ }
+
+ if (tsflags & SOF_TIMESTAMPING_TX_SOFTWARE)
+ flags |= SKBTX_SW_TSTAMP;
+
+ if (tsflags & SOF_TIMESTAMPING_TX_SCHED)
+ flags |= SKBTX_SCHED_TSTAMP;
+
+ *tx_flags = flags;
+}
+EXPORT_SYMBOL(__sock_tx_timestamp);
+
+INDIRECT_CALLABLE_DECLARE(int inet_sendmsg(struct socket *, struct msghdr *,
+ size_t));
+INDIRECT_CALLABLE_DECLARE(int inet6_sendmsg(struct socket *, struct msghdr *,
+ size_t));
+static inline int sock_sendmsg_nosec(struct socket *sock, struct msghdr *msg)
+{
+ int ret = INDIRECT_CALL_INET(sock->ops->sendmsg, inet6_sendmsg,
+ inet_sendmsg, sock, msg,
+ msg_data_left(msg));
+ BUG_ON(ret == -EIOCBQUEUED);
+ return ret;
+}
+
+static int __sock_sendmsg(struct socket *sock, struct msghdr *msg)
+{
+ int err = security_socket_sendmsg(sock, msg,
+ msg_data_left(msg));
+
+ return err ?: sock_sendmsg_nosec(sock, msg);
+}
+
+/**
+ * sock_sendmsg - send a message through @sock
+ * @sock: socket
+ * @msg: message to send
+ *
+ * Sends @msg through @sock, passing through LSM.
+ * Returns the number of bytes sent, or an error code.
+ */
+int sock_sendmsg(struct socket *sock, struct msghdr *msg)
+{
+ struct sockaddr_storage *save_addr = (struct sockaddr_storage *)msg->msg_name;
+ struct sockaddr_storage address;
+ int save_len = msg->msg_namelen;
+ int ret;
+
+ if (msg->msg_name) {
+ memcpy(&address, msg->msg_name, msg->msg_namelen);
+ msg->msg_name = &address;
+ }
+
+ ret = __sock_sendmsg(sock, msg);
+ msg->msg_name = save_addr;
+ msg->msg_namelen = save_len;
+
+ return ret;
+}
+EXPORT_SYMBOL(sock_sendmsg);
+
+/**
+ * kernel_sendmsg - send a message through @sock (kernel-space)
+ * @sock: socket
+ * @msg: message header
+ * @vec: kernel vec
+ * @num: vec array length
+ * @size: total message data size
+ *
+ * Builds the message data with @vec and sends it through @sock.
+ * Returns the number of bytes sent, or an error code.
+ */
+
+int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
+ struct kvec *vec, size_t num, size_t size)
+{
+ iov_iter_kvec(&msg->msg_iter, ITER_SOURCE, vec, num, size);
+ return sock_sendmsg(sock, msg);
+}
+EXPORT_SYMBOL(kernel_sendmsg);
+
+/**
+ * kernel_sendmsg_locked - send a message through @sock (kernel-space)
+ * @sk: sock
+ * @msg: message header
+ * @vec: output s/g array
+ * @num: output s/g array length
+ * @size: total message data size
+ *
+ * Builds the message data with @vec and sends it through @sock.
+ * Returns the number of bytes sent, or an error code.
+ * Caller must hold @sk.
+ */
+
+int kernel_sendmsg_locked(struct sock *sk, struct msghdr *msg,
+ struct kvec *vec, size_t num, size_t size)
+{
+ struct socket *sock = sk->sk_socket;
+
+ if (!sock->ops->sendmsg_locked)
+ return sock_no_sendmsg_locked(sk, msg, size);
+
+ iov_iter_kvec(&msg->msg_iter, ITER_SOURCE, vec, num, size);
+
+ return sock->ops->sendmsg_locked(sk, msg, msg_data_left(msg));
+}
+EXPORT_SYMBOL(kernel_sendmsg_locked);
+
+static bool skb_is_err_queue(const struct sk_buff *skb)
+{
+ /* pkt_type of skbs enqueued on the error queue are set to
+ * PACKET_OUTGOING in skb_set_err_queue(). This is only safe to do
+ * in recvmsg, since skbs received on a local socket will never
+ * have a pkt_type of PACKET_OUTGOING.
+ */
+ return skb->pkt_type == PACKET_OUTGOING;
+}
+
+/* On transmit, software and hardware timestamps are returned independently.
+ * As the two skb clones share the hardware timestamp, which may be updated
+ * before the software timestamp is received, a hardware TX timestamp may be
+ * returned only if there is no software TX timestamp. Ignore false software
+ * timestamps, which may be made in the __sock_recv_timestamp() call when the
+ * option SO_TIMESTAMP_OLD(NS) is enabled on the socket, even when the skb has a
+ * hardware timestamp.
+ */
+static bool skb_is_swtx_tstamp(const struct sk_buff *skb, int false_tstamp)
+{
+ return skb->tstamp && !false_tstamp && skb_is_err_queue(skb);
+}
+
+static ktime_t get_timestamp(struct sock *sk, struct sk_buff *skb, int *if_index)
+{
+ bool cycles = READ_ONCE(sk->sk_tsflags) & SOF_TIMESTAMPING_BIND_PHC;
+ struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
+ struct net_device *orig_dev;
+ ktime_t hwtstamp;
+
+ rcu_read_lock();
+ orig_dev = dev_get_by_napi_id(skb_napi_id(skb));
+ if (orig_dev) {
+ *if_index = orig_dev->ifindex;
+ hwtstamp = netdev_get_tstamp(orig_dev, shhwtstamps, cycles);
+ } else {
+ hwtstamp = shhwtstamps->hwtstamp;
+ }
+ rcu_read_unlock();
+
+ return hwtstamp;
+}
+
+static void put_ts_pktinfo(struct msghdr *msg, struct sk_buff *skb,
+ int if_index)
+{
+ struct scm_ts_pktinfo ts_pktinfo;
+ struct net_device *orig_dev;
+
+ if (!skb_mac_header_was_set(skb))
+ return;
+
+ memset(&ts_pktinfo, 0, sizeof(ts_pktinfo));
+
+ if (!if_index) {
+ rcu_read_lock();
+ orig_dev = dev_get_by_napi_id(skb_napi_id(skb));
+ if (orig_dev)
+ if_index = orig_dev->ifindex;
+ rcu_read_unlock();
+ }
+ ts_pktinfo.if_index = if_index;
+
+ ts_pktinfo.pkt_length = skb->len - skb_mac_offset(skb);
+ put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_PKTINFO,
+ sizeof(ts_pktinfo), &ts_pktinfo);
+}
+
+/*
+ * called from sock_recv_timestamp() if sock_flag(sk, SOCK_RCVTSTAMP)
+ */
+void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
+ struct sk_buff *skb)
+{
+ int need_software_tstamp = sock_flag(sk, SOCK_RCVTSTAMP);
+ int new_tstamp = sock_flag(sk, SOCK_TSTAMP_NEW);
+ struct scm_timestamping_internal tss;
+ int empty = 1, false_tstamp = 0;
+ struct skb_shared_hwtstamps *shhwtstamps =
+ skb_hwtstamps(skb);
+ int if_index;
+ ktime_t hwtstamp;
+ u32 tsflags;
+
+ /* Race occurred between timestamp enabling and packet
+ receiving. Fill in the current time for now. */
+ if (need_software_tstamp && skb->tstamp == 0) {
+ __net_timestamp(skb);
+ false_tstamp = 1;
+ }
+
+ if (need_software_tstamp) {
+ if (!sock_flag(sk, SOCK_RCVTSTAMPNS)) {
+ if (new_tstamp) {
+ struct __kernel_sock_timeval tv;
+
+ skb_get_new_timestamp(skb, &tv);
+ put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_NEW,
+ sizeof(tv), &tv);
+ } else {
+ struct __kernel_old_timeval tv;
+
+ skb_get_timestamp(skb, &tv);
+ put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_OLD,
+ sizeof(tv), &tv);
+ }
+ } else {
+ if (new_tstamp) {
+ struct __kernel_timespec ts;
+
+ skb_get_new_timestampns(skb, &ts);
+ put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPNS_NEW,
+ sizeof(ts), &ts);
+ } else {
+ struct __kernel_old_timespec ts;
+
+ skb_get_timestampns(skb, &ts);
+ put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPNS_OLD,
+ sizeof(ts), &ts);
+ }
+ }
+ }
+
+ memset(&tss, 0, sizeof(tss));
+ tsflags = READ_ONCE(sk->sk_tsflags);
+ if ((tsflags & SOF_TIMESTAMPING_SOFTWARE) &&
+ ktime_to_timespec64_cond(skb->tstamp, tss.ts + 0))
+ empty = 0;
+ if (shhwtstamps &&
+ (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
+ !skb_is_swtx_tstamp(skb, false_tstamp)) {
+ if_index = 0;
+ if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP_NETDEV)
+ hwtstamp = get_timestamp(sk, skb, &if_index);
+ else
+ hwtstamp = shhwtstamps->hwtstamp;
+
+ if (tsflags & SOF_TIMESTAMPING_BIND_PHC)
+ hwtstamp = ptp_convert_timestamp(&hwtstamp,
+ READ_ONCE(sk->sk_bind_phc));
+
+ if (ktime_to_timespec64_cond(hwtstamp, tss.ts + 2)) {
+ empty = 0;
+
+ if ((tsflags & SOF_TIMESTAMPING_OPT_PKTINFO) &&
+ !skb_is_err_queue(skb))
+ put_ts_pktinfo(msg, skb, if_index);
+ }
+ }
+ if (!empty) {
+ if (sock_flag(sk, SOCK_TSTAMP_NEW))
+ put_cmsg_scm_timestamping64(msg, &tss);
+ else
+ put_cmsg_scm_timestamping(msg, &tss);
+
+ if (skb_is_err_queue(skb) && skb->len &&
+ SKB_EXT_ERR(skb)->opt_stats)
+ put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_OPT_STATS,
+ skb->len, skb->data);
+ }
+}
+EXPORT_SYMBOL_GPL(__sock_recv_timestamp);
+
+void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
+ struct sk_buff *skb)
+{
+ int ack;
+
+ if (!sock_flag(sk, SOCK_WIFI_STATUS))
+ return;
+ if (!skb->wifi_acked_valid)
+ return;
+
+ ack = skb->wifi_acked;
+
+ put_cmsg(msg, SOL_SOCKET, SCM_WIFI_STATUS, sizeof(ack), &ack);
+}
+EXPORT_SYMBOL_GPL(__sock_recv_wifi_status);
+
+static inline void sock_recv_drops(struct msghdr *msg, struct sock *sk,
+ struct sk_buff *skb)
+{
+ if (sock_flag(sk, SOCK_RXQ_OVFL) && skb && SOCK_SKB_CB(skb)->dropcount)
+ put_cmsg(msg, SOL_SOCKET, SO_RXQ_OVFL,
+ sizeof(__u32), &SOCK_SKB_CB(skb)->dropcount);
+}
+
+static void sock_recv_mark(struct msghdr *msg, struct sock *sk,
+ struct sk_buff *skb)
+{
+ if (sock_flag(sk, SOCK_RCVMARK) && skb) {
+ /* We must use a bounce buffer for CONFIG_HARDENED_USERCOPY=y */
+ __u32 mark = skb->mark;
+
+ put_cmsg(msg, SOL_SOCKET, SO_MARK, sizeof(__u32), &mark);
+ }
+}
+
+void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
+ struct sk_buff *skb)
+{
+ sock_recv_timestamp(msg, sk, skb);
+ sock_recv_drops(msg, sk, skb);
+ sock_recv_mark(msg, sk, skb);
+}
+EXPORT_SYMBOL_GPL(__sock_recv_cmsgs);
+
+INDIRECT_CALLABLE_DECLARE(int inet_recvmsg(struct socket *, struct msghdr *,
+ size_t, int));
+INDIRECT_CALLABLE_DECLARE(int inet6_recvmsg(struct socket *, struct msghdr *,
+ size_t, int));
+static inline int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg,
+ int flags)
+{
+ return INDIRECT_CALL_INET(sock->ops->recvmsg, inet6_recvmsg,
+ inet_recvmsg, sock, msg, msg_data_left(msg),
+ flags);
+}
+
+/**
+ * sock_recvmsg - receive a message from @sock
+ * @sock: socket
+ * @msg: message to receive
+ * @flags: message flags
+ *
+ * Receives @msg from @sock, passing through LSM. Returns the total number
+ * of bytes received, or an error.
+ */
+int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags)
+{
+ int err = security_socket_recvmsg(sock, msg, msg_data_left(msg), flags);
+
+ return err ?: sock_recvmsg_nosec(sock, msg, flags);
+}
+EXPORT_SYMBOL(sock_recvmsg);
+
+/**
+ * kernel_recvmsg - Receive a message from a socket (kernel space)
+ * @sock: The socket to receive the message from
+ * @msg: Received message
+ * @vec: Input s/g array for message data
+ * @num: Size of input s/g array
+ * @size: Number of bytes to read
+ * @flags: Message flags (MSG_DONTWAIT, etc...)
+ *
+ * On return the msg structure contains the scatter/gather array passed in the
+ * vec argument. The array is modified so that it consists of the unfilled
+ * portion of the original array.
+ *
+ * The returned value is the total number of bytes received, or an error.
+ */
+
+int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
+ struct kvec *vec, size_t num, size_t size, int flags)
+{
+ msg->msg_control_is_user = false;
+ iov_iter_kvec(&msg->msg_iter, ITER_DEST, vec, num, size);
+ return sock_recvmsg(sock, msg, flags);
+}
+EXPORT_SYMBOL(kernel_recvmsg);
+
+static ssize_t sock_sendpage(struct file *file, struct page *page,
+ int offset, size_t size, loff_t *ppos, int more)
+{
+ struct socket *sock;
+ int flags;
+
+ sock = file->private_data;
+
+ flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
+ /* more is a combination of MSG_MORE and MSG_SENDPAGE_NOTLAST */
+ flags |= more;
+
+ return kernel_sendpage(sock, page, offset, size, flags);
+}
+
+static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
+ struct pipe_inode_info *pipe, size_t len,
+ unsigned int flags)
+{
+ struct socket *sock = file->private_data;
+
+ if (unlikely(!sock->ops->splice_read))
+ return generic_file_splice_read(file, ppos, pipe, len, flags);
+
+ return sock->ops->splice_read(sock, ppos, pipe, len, flags);
+}
+
+static void sock_splice_eof(struct file *file)
+{
+ struct socket *sock = file->private_data;
+
+ if (sock->ops->splice_eof)
+ sock->ops->splice_eof(sock);
+}
+
+static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+ struct file *file = iocb->ki_filp;
+ struct socket *sock = file->private_data;
+ struct msghdr msg = {.msg_iter = *to,
+ .msg_iocb = iocb};
+ ssize_t res;
+
+ if (file->f_flags & O_NONBLOCK || (iocb->ki_flags & IOCB_NOWAIT))
+ msg.msg_flags = MSG_DONTWAIT;
+
+ if (iocb->ki_pos != 0)
+ return -ESPIPE;
+
+ if (!iov_iter_count(to)) /* Match SYS5 behaviour */
+ return 0;
+
+ res = sock_recvmsg(sock, &msg, msg.msg_flags);
+ *to = msg.msg_iter;
+ return res;
+}
+
+static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+ struct file *file = iocb->ki_filp;
+ struct socket *sock = file->private_data;
+ struct msghdr msg = {.msg_iter = *from,
+ .msg_iocb = iocb};
+ ssize_t res;
+
+ if (iocb->ki_pos != 0)
+ return -ESPIPE;
+
+ if (file->f_flags & O_NONBLOCK || (iocb->ki_flags & IOCB_NOWAIT))
+ msg.msg_flags = MSG_DONTWAIT;
+
+ if (sock->type == SOCK_SEQPACKET)
+ msg.msg_flags |= MSG_EOR;
+
+ res = __sock_sendmsg(sock, &msg);
+ *from = msg.msg_iter;
+ return res;
+}
+
+/*
+ * Atomic setting of ioctl hooks to avoid race
+ * with module unload.
+ */
+
+static DEFINE_MUTEX(br_ioctl_mutex);
+static int (*br_ioctl_hook)(struct net *net, struct net_bridge *br,
+ unsigned int cmd, struct ifreq *ifr,
+ void __user *uarg);
+
+void brioctl_set(int (*hook)(struct net *net, struct net_bridge *br,
+ unsigned int cmd, struct ifreq *ifr,
+ void __user *uarg))
+{
+ mutex_lock(&br_ioctl_mutex);
+ br_ioctl_hook = hook;
+ mutex_unlock(&br_ioctl_mutex);
+}
+EXPORT_SYMBOL(brioctl_set);
+
+int br_ioctl_call(struct net *net, struct net_bridge *br, unsigned int cmd,
+ struct ifreq *ifr, void __user *uarg)
+{
+ int err = -ENOPKG;
+
+ if (!br_ioctl_hook)
+ request_module("bridge");
+
+ mutex_lock(&br_ioctl_mutex);
+ if (br_ioctl_hook)
+ err = br_ioctl_hook(net, br, cmd, ifr, uarg);
+ mutex_unlock(&br_ioctl_mutex);
+
+ return err;
+}
+
+static DEFINE_MUTEX(vlan_ioctl_mutex);
+static int (*vlan_ioctl_hook) (struct net *, void __user *arg);
+
+void vlan_ioctl_set(int (*hook) (struct net *, void __user *))
+{
+ mutex_lock(&vlan_ioctl_mutex);
+ vlan_ioctl_hook = hook;
+ mutex_unlock(&vlan_ioctl_mutex);
+}
+EXPORT_SYMBOL(vlan_ioctl_set);
+
+static long sock_do_ioctl(struct net *net, struct socket *sock,
+ unsigned int cmd, unsigned long arg)
+{
+ struct ifreq ifr;
+ bool need_copyout;
+ int err;
+ void __user *argp = (void __user *)arg;
+ void __user *data;
+
+ err = sock->ops->ioctl(sock, cmd, arg);
+
+ /*
+ * If this ioctl is unknown try to hand it down
+ * to the NIC driver.
+ */
+ if (err != -ENOIOCTLCMD)
+ return err;
+
+ if (!is_socket_ioctl_cmd(cmd))
+ return -ENOTTY;
+
+ if (get_user_ifreq(&ifr, &data, argp))
+ return -EFAULT;
+ err = dev_ioctl(net, cmd, &ifr, data, &need_copyout);
+ if (!err && need_copyout)
+ if (put_user_ifreq(&ifr, argp))
+ return -EFAULT;
+
+ return err;
+}
+
+/*
+ * With an ioctl, arg may well be a user mode pointer, but we don't know
+ * what to do with it - that's up to the protocol still.
+ */
+
+static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
+{
+ struct socket *sock;
+ struct sock *sk;
+ void __user *argp = (void __user *)arg;
+ int pid, err;
+ struct net *net;
+
+ sock = file->private_data;
+ sk = sock->sk;
+ net = sock_net(sk);
+ if (unlikely(cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15))) {
+ struct ifreq ifr;
+ void __user *data;
+ bool need_copyout;
+ if (get_user_ifreq(&ifr, &data, argp))
+ return -EFAULT;
+ err = dev_ioctl(net, cmd, &ifr, data, &need_copyout);
+ if (!err && need_copyout)
+ if (put_user_ifreq(&ifr, argp))
+ return -EFAULT;
+ } else
+#ifdef CONFIG_WEXT_CORE
+ if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
+ err = wext_handle_ioctl(net, cmd, argp);
+ } else
+#endif
+ switch (cmd) {
+ case FIOSETOWN:
+ case SIOCSPGRP:
+ err = -EFAULT;
+ if (get_user(pid, (int __user *)argp))
+ break;
+ err = f_setown(sock->file, pid, 1);
+ break;
+ case FIOGETOWN:
+ case SIOCGPGRP:
+ err = put_user(f_getown(sock->file),
+ (int __user *)argp);
+ break;
+ case SIOCGIFBR:
+ case SIOCSIFBR:
+ case SIOCBRADDBR:
+ case SIOCBRDELBR:
+ err = br_ioctl_call(net, NULL, cmd, NULL, argp);
+ break;
+ case SIOCGIFVLAN:
+ case SIOCSIFVLAN:
+ err = -ENOPKG;
+ if (!vlan_ioctl_hook)
+ request_module("8021q");
+
+ mutex_lock(&vlan_ioctl_mutex);
+ if (vlan_ioctl_hook)
+ err = vlan_ioctl_hook(net, argp);
+ mutex_unlock(&vlan_ioctl_mutex);
+ break;
+ case SIOCGSKNS:
+ err = -EPERM;
+ if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
+ break;
+
+ err = open_related_ns(&net->ns, get_net_ns);
+ break;
+ case SIOCGSTAMP_OLD:
+ case SIOCGSTAMPNS_OLD:
+ if (!sock->ops->gettstamp) {
+ err = -ENOIOCTLCMD;
+ break;
+ }
+ err = sock->ops->gettstamp(sock, argp,
+ cmd == SIOCGSTAMP_OLD,
+ !IS_ENABLED(CONFIG_64BIT));
+ break;
+ case SIOCGSTAMP_NEW:
+ case SIOCGSTAMPNS_NEW:
+ if (!sock->ops->gettstamp) {
+ err = -ENOIOCTLCMD;
+ break;
+ }
+ err = sock->ops->gettstamp(sock, argp,
+ cmd == SIOCGSTAMP_NEW,
+ false);
+ break;
+
+ case SIOCGIFCONF:
+ err = dev_ifconf(net, argp);
+ break;
+
+ default:
+ err = sock_do_ioctl(net, sock, cmd, arg);
+ break;
+ }
+ return err;
+}
+
+/**
+ * sock_create_lite - creates a socket
+ * @family: protocol family (AF_INET, ...)
+ * @type: communication type (SOCK_STREAM, ...)
+ * @protocol: protocol (0, ...)
+ * @res: new socket
+ *
+ * Creates a new socket and assigns it to @res, passing through LSM.
+ * The new socket initialization is not complete, see kernel_accept().
+ * Returns 0 or an error. On failure @res is set to %NULL.
+ * This function internally uses GFP_KERNEL.
+ */
+
+int sock_create_lite(int family, int type, int protocol, struct socket **res)
+{
+ int err;
+ struct socket *sock = NULL;
+
+ err = security_socket_create(family, type, protocol, 1);
+ if (err)
+ goto out;
+
+ sock = sock_alloc();
+ if (!sock) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ sock->type = type;
+ err = security_socket_post_create(sock, family, type, protocol, 1);
+ if (err)
+ goto out_release;
+
+out:
+ *res = sock;
+ return err;
+out_release:
+ sock_release(sock);
+ sock = NULL;
+ goto out;
+}
+EXPORT_SYMBOL(sock_create_lite);
+
+/* No kernel lock held - perfect */
+static __poll_t sock_poll(struct file *file, poll_table *wait)
+{
+ struct socket *sock = file->private_data;
+ __poll_t events = poll_requested_events(wait), flag = 0;
+
+ if (!sock->ops->poll)
+ return 0;
+
+ if (sk_can_busy_loop(sock->sk)) {
+ /* poll once if requested by the syscall */
+ if (events & POLL_BUSY_LOOP)
+ sk_busy_loop(sock->sk, 1);
+
+ /* if this socket can poll_ll, tell the system call */
+ flag = POLL_BUSY_LOOP;
+ }
+
+ return sock->ops->poll(file, sock, wait) | flag;
+}
+
+static int sock_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct socket *sock = file->private_data;
+
+ return sock->ops->mmap(file, sock, vma);
+}
+
+static int sock_close(struct inode *inode, struct file *filp)
+{
+ __sock_release(SOCKET_I(inode), inode);
+ return 0;
+}
+
+/*
+ * Update the socket async list
+ *
+ * Fasync_list locking strategy.
+ *
+ * 1. fasync_list is modified only under process context socket lock
+ * i.e. under semaphore.
+ * 2. fasync_list is used under read_lock(&sk->sk_callback_lock)
+ * or under socket lock
+ */
+
+static int sock_fasync(int fd, struct file *filp, int on)
+{
+ struct socket *sock = filp->private_data;
+ struct sock *sk = sock->sk;
+ struct socket_wq *wq = &sock->wq;
+
+ if (sk == NULL)
+ return -EINVAL;
+
+ lock_sock(sk);
+ fasync_helper(fd, filp, on, &wq->fasync_list);
+
+ if (!wq->fasync_list)
+ sock_reset_flag(sk, SOCK_FASYNC);
+ else
+ sock_set_flag(sk, SOCK_FASYNC);
+
+ release_sock(sk);
+ return 0;
+}
+
+/* This function may be called only under rcu_lock */
+
+int sock_wake_async(struct socket_wq *wq, int how, int band)
+{
+ if (!wq || !wq->fasync_list)
+ return -1;
+
+ switch (how) {
+ case SOCK_WAKE_WAITD:
+ if (test_bit(SOCKWQ_ASYNC_WAITDATA, &wq->flags))
+ break;
+ goto call_kill;
+ case SOCK_WAKE_SPACE:
+ if (!test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags))
+ break;
+ fallthrough;
+ case SOCK_WAKE_IO:
+call_kill:
+ kill_fasync(&wq->fasync_list, SIGIO, band);
+ break;
+ case SOCK_WAKE_URG:
+ kill_fasync(&wq->fasync_list, SIGURG, band);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(sock_wake_async);
+
+/**
+ * __sock_create - creates a socket
+ * @net: net namespace
+ * @family: protocol family (AF_INET, ...)
+ * @type: communication type (SOCK_STREAM, ...)
+ * @protocol: protocol (0, ...)
+ * @res: new socket
+ * @kern: boolean for kernel space sockets
+ *
+ * Creates a new socket and assigns it to @res, passing through LSM.
+ * Returns 0 or an error. On failure @res is set to %NULL. @kern must
+ * be set to true if the socket resides in kernel space.
+ * This function internally uses GFP_KERNEL.
+ */
+
+int __sock_create(struct net *net, int family, int type, int protocol,
+ struct socket **res, int kern)
+{
+ int err;
+ struct socket *sock;
+ const struct net_proto_family *pf;
+
+ /*
+ * Check protocol is in range
+ */
+ if (family < 0 || family >= NPROTO)
+ return -EAFNOSUPPORT;
+ if (type < 0 || type >= SOCK_MAX)
+ return -EINVAL;
+
+ /* Compatibility.
+
+ This uglymoron is moved from INET layer to here to avoid
+ deadlock in module load.
+ */
+ if (family == PF_INET && type == SOCK_PACKET) {
+ pr_info_once("%s uses obsolete (PF_INET,SOCK_PACKET)\n",
+ current->comm);
+ family = PF_PACKET;
+ }
+
+ err = security_socket_create(family, type, protocol, kern);
+ if (err)
+ return err;
+
+ /*
+ * Allocate the socket and allow the family to set things up. if
+ * the protocol is 0, the family is instructed to select an appropriate
+ * default.
+ */
+ sock = sock_alloc();
+ if (!sock) {
+ net_warn_ratelimited("socket: no more sockets\n");
+ return -ENFILE; /* Not exactly a match, but its the
+ closest posix thing */
+ }
+
+ sock->type = type;
+
+#ifdef CONFIG_MODULES
+ /* Attempt to load a protocol module if the find failed.
+ *
+ * 12/09/1996 Marcin: But! this makes REALLY only sense, if the user
+ * requested real, full-featured networking support upon configuration.
+ * Otherwise module support will break!
+ */
+ if (rcu_access_pointer(net_families[family]) == NULL)
+ request_module("net-pf-%d", family);
+#endif
+
+ rcu_read_lock();
+ pf = rcu_dereference(net_families[family]);
+ err = -EAFNOSUPPORT;
+ if (!pf)
+ goto out_release;
+
+ /*
+ * We will call the ->create function, that possibly is in a loadable
+ * module, so we have to bump that loadable module refcnt first.
+ */
+ if (!try_module_get(pf->owner))
+ goto out_release;
+
+ /* Now protected by module ref count */
+ rcu_read_unlock();
+
+ err = pf->create(net, sock, protocol, kern);
+ if (err < 0)
+ goto out_module_put;
+
+ /*
+ * Now to bump the refcnt of the [loadable] module that owns this
+ * socket at sock_release time we decrement its refcnt.
+ */
+ if (!try_module_get(sock->ops->owner))
+ goto out_module_busy;
+
+ /*
+ * Now that we're done with the ->create function, the [loadable]
+ * module can have its refcnt decremented
+ */
+ module_put(pf->owner);
+ err = security_socket_post_create(sock, family, type, protocol, kern);
+ if (err)
+ goto out_sock_release;
+ *res = sock;
+
+ return 0;
+
+out_module_busy:
+ err = -EAFNOSUPPORT;
+out_module_put:
+ sock->ops = NULL;
+ module_put(pf->owner);
+out_sock_release:
+ sock_release(sock);
+ return err;
+
+out_release:
+ rcu_read_unlock();
+ goto out_sock_release;
+}
+EXPORT_SYMBOL(__sock_create);
+
+/**
+ * sock_create - creates a socket
+ * @family: protocol family (AF_INET, ...)
+ * @type: communication type (SOCK_STREAM, ...)
+ * @protocol: protocol (0, ...)
+ * @res: new socket
+ *
+ * A wrapper around __sock_create().
+ * Returns 0 or an error. This function internally uses GFP_KERNEL.
+ */
+
+int sock_create(int family, int type, int protocol, struct socket **res)
+{
+ return __sock_create(current->nsproxy->net_ns, family, type, protocol, res, 0);
+}
+EXPORT_SYMBOL(sock_create);
+
+/**
+ * sock_create_kern - creates a socket (kernel space)
+ * @net: net namespace
+ * @family: protocol family (AF_INET, ...)
+ * @type: communication type (SOCK_STREAM, ...)
+ * @protocol: protocol (0, ...)
+ * @res: new socket
+ *
+ * A wrapper around __sock_create().
+ * Returns 0 or an error. This function internally uses GFP_KERNEL.
+ */
+
+int sock_create_kern(struct net *net, int family, int type, int protocol, struct socket **res)
+{
+ return __sock_create(net, family, type, protocol, res, 1);
+}
+EXPORT_SYMBOL(sock_create_kern);
+
+static struct socket *__sys_socket_create(int family, int type, int protocol)
+{
+ struct socket *sock;
+ int retval;
+
+ /* Check the SOCK_* constants for consistency. */
+ BUILD_BUG_ON(SOCK_CLOEXEC != O_CLOEXEC);
+ BUILD_BUG_ON((SOCK_MAX | SOCK_TYPE_MASK) != SOCK_TYPE_MASK);
+ BUILD_BUG_ON(SOCK_CLOEXEC & SOCK_TYPE_MASK);
+ BUILD_BUG_ON(SOCK_NONBLOCK & SOCK_TYPE_MASK);
+
+ if ((type & ~SOCK_TYPE_MASK) & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
+ return ERR_PTR(-EINVAL);
+ type &= SOCK_TYPE_MASK;
+
+ retval = sock_create(family, type, protocol, &sock);
+ if (retval < 0)
+ return ERR_PTR(retval);
+
+ return sock;
+}
+
+struct file *__sys_socket_file(int family, int type, int protocol)
+{
+ struct socket *sock;
+ int flags;
+
+ sock = __sys_socket_create(family, type, protocol);
+ if (IS_ERR(sock))
+ return ERR_CAST(sock);
+
+ flags = type & ~SOCK_TYPE_MASK;
+ if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
+ flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
+
+ return sock_alloc_file(sock, flags, NULL);
+}
+
+int __sys_socket(int family, int type, int protocol)
+{
+ struct socket *sock;
+ int flags;
+
+ sock = __sys_socket_create(family, type, protocol);
+ if (IS_ERR(sock))
+ return PTR_ERR(sock);
+
+ flags = type & ~SOCK_TYPE_MASK;
+ if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
+ flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
+
+ return sock_map_fd(sock, flags & (O_CLOEXEC | O_NONBLOCK));
+}
+
+SYSCALL_DEFINE3(socket, int, family, int, type, int, protocol)
+{
+ return __sys_socket(family, type, protocol);
+}
+
+/*
+ * Create a pair of connected sockets.
+ */
+
+int __sys_socketpair(int family, int type, int protocol, int __user *usockvec)
+{
+ struct socket *sock1, *sock2;
+ int fd1, fd2, err;
+ struct file *newfile1, *newfile2;
+ int flags;
+
+ flags = type & ~SOCK_TYPE_MASK;
+ if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
+ return -EINVAL;
+ type &= SOCK_TYPE_MASK;
+
+ if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
+ flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
+
+ /*
+ * reserve descriptors and make sure we won't fail
+ * to return them to userland.
+ */
+ fd1 = get_unused_fd_flags(flags);
+ if (unlikely(fd1 < 0))
+ return fd1;
+
+ fd2 = get_unused_fd_flags(flags);
+ if (unlikely(fd2 < 0)) {
+ put_unused_fd(fd1);
+ return fd2;
+ }
+
+ err = put_user(fd1, &usockvec[0]);
+ if (err)
+ goto out;
+
+ err = put_user(fd2, &usockvec[1]);
+ if (err)
+ goto out;
+
+ /*
+ * Obtain the first socket and check if the underlying protocol
+ * supports the socketpair call.
+ */
+
+ err = sock_create(family, type, protocol, &sock1);
+ if (unlikely(err < 0))
+ goto out;
+
+ err = sock_create(family, type, protocol, &sock2);
+ if (unlikely(err < 0)) {
+ sock_release(sock1);
+ goto out;
+ }
+
+ err = security_socket_socketpair(sock1, sock2);
+ if (unlikely(err)) {
+ sock_release(sock2);
+ sock_release(sock1);
+ goto out;
+ }
+
+ err = sock1->ops->socketpair(sock1, sock2);
+ if (unlikely(err < 0)) {
+ sock_release(sock2);
+ sock_release(sock1);
+ goto out;
+ }
+
+ newfile1 = sock_alloc_file(sock1, flags, NULL);
+ if (IS_ERR(newfile1)) {
+ err = PTR_ERR(newfile1);
+ sock_release(sock2);
+ goto out;
+ }
+
+ newfile2 = sock_alloc_file(sock2, flags, NULL);
+ if (IS_ERR(newfile2)) {
+ err = PTR_ERR(newfile2);
+ fput(newfile1);
+ goto out;
+ }
+
+ audit_fd_pair(fd1, fd2);
+
+ fd_install(fd1, newfile1);
+ fd_install(fd2, newfile2);
+ return 0;
+
+out:
+ put_unused_fd(fd2);
+ put_unused_fd(fd1);
+ return err;
+}
+
+SYSCALL_DEFINE4(socketpair, int, family, int, type, int, protocol,
+ int __user *, usockvec)
+{
+ return __sys_socketpair(family, type, protocol, usockvec);
+}
+
+/*
+ * Bind a name to a socket. Nothing much to do here since it's
+ * the protocol's responsibility to handle the local address.
+ *
+ * We move the socket address to kernel space before we call
+ * the protocol layer (having also checked the address is ok).
+ */
+
+int __sys_bind(int fd, struct sockaddr __user *umyaddr, int addrlen)
+{
+ struct socket *sock;
+ struct sockaddr_storage address;
+ int err, fput_needed;
+
+ sock = sockfd_lookup_light(fd, &err, &fput_needed);
+ if (sock) {
+ err = move_addr_to_kernel(umyaddr, addrlen, &address);
+ if (!err) {
+ err = security_socket_bind(sock,
+ (struct sockaddr *)&address,
+ addrlen);
+ if (!err)
+ err = sock->ops->bind(sock,
+ (struct sockaddr *)
+ &address, addrlen);
+ }
+ fput_light(sock->file, fput_needed);
+ }
+ return err;
+}
+
+SYSCALL_DEFINE3(bind, int, fd, struct sockaddr __user *, umyaddr, int, addrlen)
+{
+ return __sys_bind(fd, umyaddr, addrlen);
+}
+
+/*
+ * Perform a listen. Basically, we allow the protocol to do anything
+ * necessary for a listen, and if that works, we mark the socket as
+ * ready for listening.
+ */
+
+int __sys_listen(int fd, int backlog)
+{
+ struct socket *sock;
+ int err, fput_needed;
+ int somaxconn;
+
+ sock = sockfd_lookup_light(fd, &err, &fput_needed);
+ if (sock) {
+ somaxconn = READ_ONCE(sock_net(sock->sk)->core.sysctl_somaxconn);
+ if ((unsigned int)backlog > somaxconn)
+ backlog = somaxconn;
+
+ err = security_socket_listen(sock, backlog);
+ if (!err)
+ err = sock->ops->listen(sock, backlog);
+
+ fput_light(sock->file, fput_needed);
+ }
+ return err;
+}
+
+SYSCALL_DEFINE2(listen, int, fd, int, backlog)
+{
+ return __sys_listen(fd, backlog);
+}
+
+struct file *do_accept(struct file *file, unsigned file_flags,
+ struct sockaddr __user *upeer_sockaddr,
+ int __user *upeer_addrlen, int flags)
+{
+ struct socket *sock, *newsock;
+ struct file *newfile;
+ int err, len;
+ struct sockaddr_storage address;
+
+ sock = sock_from_file(file);
+ if (!sock)
+ return ERR_PTR(-ENOTSOCK);
+
+ newsock = sock_alloc();
+ if (!newsock)
+ return ERR_PTR(-ENFILE);
+
+ newsock->type = sock->type;
+ newsock->ops = sock->ops;
+
+ /*
+ * We don't need try_module_get here, as the listening socket (sock)
+ * has the protocol module (sock->ops->owner) held.
+ */
+ __module_get(newsock->ops->owner);
+
+ newfile = sock_alloc_file(newsock, flags, sock->sk->sk_prot_creator->name);
+ if (IS_ERR(newfile))
+ return newfile;
+
+ err = security_socket_accept(sock, newsock);
+ if (err)
+ goto out_fd;
+
+ err = sock->ops->accept(sock, newsock, sock->file->f_flags | file_flags,
+ false);
+ if (err < 0)
+ goto out_fd;
+
+ if (upeer_sockaddr) {
+ len = newsock->ops->getname(newsock,
+ (struct sockaddr *)&address, 2);
+ if (len < 0) {
+ err = -ECONNABORTED;
+ goto out_fd;
+ }
+ err = move_addr_to_user(&address,
+ len, upeer_sockaddr, upeer_addrlen);
+ if (err < 0)
+ goto out_fd;
+ }
+
+ /* File flags are not inherited via accept() unlike another OSes. */
+ return newfile;
+out_fd:
+ fput(newfile);
+ return ERR_PTR(err);
+}
+
+static int __sys_accept4_file(struct file *file, struct sockaddr __user *upeer_sockaddr,
+ int __user *upeer_addrlen, int flags)
+{
+ struct file *newfile;
+ int newfd;
+
+ if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
+ return -EINVAL;
+
+ if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
+ flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
+
+ newfd = get_unused_fd_flags(flags);
+ if (unlikely(newfd < 0))
+ return newfd;
+
+ newfile = do_accept(file, 0, upeer_sockaddr, upeer_addrlen,
+ flags);
+ if (IS_ERR(newfile)) {
+ put_unused_fd(newfd);
+ return PTR_ERR(newfile);
+ }
+ fd_install(newfd, newfile);
+ return newfd;
+}
+
+/*
+ * For accept, we attempt to create a new socket, set up the link
+ * with the client, wake up the client, then return the new
+ * connected fd. We collect the address of the connector in kernel
+ * space and move it to user at the very end. This is unclean because
+ * we open the socket then return an error.
+ *
+ * 1003.1g adds the ability to recvmsg() to query connection pending
+ * status to recvmsg. We need to add that support in a way thats
+ * clean when we restructure accept also.
+ */
+
+int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr,
+ int __user *upeer_addrlen, int flags)
+{
+ int ret = -EBADF;
+ struct fd f;
+
+ f = fdget(fd);
+ if (f.file) {
+ ret = __sys_accept4_file(f.file, upeer_sockaddr,
+ upeer_addrlen, flags);
+ fdput(f);
+ }
+
+ return ret;
+}
+
+SYSCALL_DEFINE4(accept4, int, fd, struct sockaddr __user *, upeer_sockaddr,
+ int __user *, upeer_addrlen, int, flags)
+{
+ return __sys_accept4(fd, upeer_sockaddr, upeer_addrlen, flags);
+}
+
+SYSCALL_DEFINE3(accept, int, fd, struct sockaddr __user *, upeer_sockaddr,
+ int __user *, upeer_addrlen)
+{
+ return __sys_accept4(fd, upeer_sockaddr, upeer_addrlen, 0);
+}
+
+/*
+ * Attempt to connect to a socket with the server address. The address
+ * is in user space so we verify it is OK and move it to kernel space.
+ *
+ * For 1003.1g we need to add clean support for a bind to AF_UNSPEC to
+ * break bindings
+ *
+ * NOTE: 1003.1g draft 6.3 is broken with respect to AX.25/NetROM and
+ * other SEQPACKET protocols that take time to connect() as it doesn't
+ * include the -EINPROGRESS status for such sockets.
+ */
+
+int __sys_connect_file(struct file *file, struct sockaddr_storage *address,
+ int addrlen, int file_flags)
+{
+ struct socket *sock;
+ int err;
+
+ sock = sock_from_file(file);
+ if (!sock) {
+ err = -ENOTSOCK;
+ goto out;
+ }
+
+ err =
+ security_socket_connect(sock, (struct sockaddr *)address, addrlen);
+ if (err)
+ goto out;
+
+ err = sock->ops->connect(sock, (struct sockaddr *)address, addrlen,
+ sock->file->f_flags | file_flags);
+out:
+ return err;
+}
+
+int __sys_connect(int fd, struct sockaddr __user *uservaddr, int addrlen)
+{
+ int ret = -EBADF;
+ struct fd f;
+
+ f = fdget(fd);
+ if (f.file) {
+ struct sockaddr_storage address;
+
+ ret = move_addr_to_kernel(uservaddr, addrlen, &address);
+ if (!ret)
+ ret = __sys_connect_file(f.file, &address, addrlen, 0);
+ fdput(f);
+ }
+
+ return ret;
+}
+
+SYSCALL_DEFINE3(connect, int, fd, struct sockaddr __user *, uservaddr,
+ int, addrlen)
+{
+ return __sys_connect(fd, uservaddr, addrlen);
+}
+
+/*
+ * Get the local address ('name') of a socket object. Move the obtained
+ * name to user space.
+ */
+
+int __sys_getsockname(int fd, struct sockaddr __user *usockaddr,
+ int __user *usockaddr_len)
+{
+ struct socket *sock;
+ struct sockaddr_storage address;
+ int err, fput_needed;
+
+ sock = sockfd_lookup_light(fd, &err, &fput_needed);
+ if (!sock)
+ goto out;
+
+ err = security_socket_getsockname(sock);
+ if (err)
+ goto out_put;
+
+ err = sock->ops->getname(sock, (struct sockaddr *)&address, 0);
+ if (err < 0)
+ goto out_put;
+ /* "err" is actually length in this case */
+ err = move_addr_to_user(&address, err, usockaddr, usockaddr_len);
+
+out_put:
+ fput_light(sock->file, fput_needed);
+out:
+ return err;
+}
+
+SYSCALL_DEFINE3(getsockname, int, fd, struct sockaddr __user *, usockaddr,
+ int __user *, usockaddr_len)
+{
+ return __sys_getsockname(fd, usockaddr, usockaddr_len);
+}
+
+/*
+ * Get the remote address ('name') of a socket object. Move the obtained
+ * name to user space.
+ */
+
+int __sys_getpeername(int fd, struct sockaddr __user *usockaddr,
+ int __user *usockaddr_len)
+{
+ struct socket *sock;
+ struct sockaddr_storage address;
+ int err, fput_needed;
+
+ sock = sockfd_lookup_light(fd, &err, &fput_needed);
+ if (sock != NULL) {
+ err = security_socket_getpeername(sock);
+ if (err) {
+ fput_light(sock->file, fput_needed);
+ return err;
+ }
+
+ err = sock->ops->getname(sock, (struct sockaddr *)&address, 1);
+ if (err >= 0)
+ /* "err" is actually length in this case */
+ err = move_addr_to_user(&address, err, usockaddr,
+ usockaddr_len);
+ fput_light(sock->file, fput_needed);
+ }
+ return err;
+}
+
+SYSCALL_DEFINE3(getpeername, int, fd, struct sockaddr __user *, usockaddr,
+ int __user *, usockaddr_len)
+{
+ return __sys_getpeername(fd, usockaddr, usockaddr_len);
+}
+
+/*
+ * Send a datagram to a given address. We move the address into kernel
+ * space and check the user space data area is readable before invoking
+ * the protocol.
+ */
+int __sys_sendto(int fd, void __user *buff, size_t len, unsigned int flags,
+ struct sockaddr __user *addr, int addr_len)
+{
+ struct socket *sock;
+ struct sockaddr_storage address;
+ int err;
+ struct msghdr msg;
+ struct iovec iov;
+ int fput_needed;
+
+ err = import_single_range(ITER_SOURCE, buff, len, &iov, &msg.msg_iter);
+ if (unlikely(err))
+ return err;
+ sock = sockfd_lookup_light(fd, &err, &fput_needed);
+ if (!sock)
+ goto out;
+
+ msg.msg_name = NULL;
+ msg.msg_control = NULL;
+ msg.msg_controllen = 0;
+ msg.msg_namelen = 0;
+ msg.msg_ubuf = NULL;
+ if (addr) {
+ err = move_addr_to_kernel(addr, addr_len, &address);
+ if (err < 0)
+ goto out_put;
+ msg.msg_name = (struct sockaddr *)&address;
+ msg.msg_namelen = addr_len;
+ }
+ flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
+ if (sock->file->f_flags & O_NONBLOCK)
+ flags |= MSG_DONTWAIT;
+ msg.msg_flags = flags;
+ err = __sock_sendmsg(sock, &msg);
+
+out_put:
+ fput_light(sock->file, fput_needed);
+out:
+ return err;
+}
+
+SYSCALL_DEFINE6(sendto, int, fd, void __user *, buff, size_t, len,
+ unsigned int, flags, struct sockaddr __user *, addr,
+ int, addr_len)
+{
+ return __sys_sendto(fd, buff, len, flags, addr, addr_len);
+}
+
+/*
+ * Send a datagram down a socket.
+ */
+
+SYSCALL_DEFINE4(send, int, fd, void __user *, buff, size_t, len,
+ unsigned int, flags)
+{
+ return __sys_sendto(fd, buff, len, flags, NULL, 0);
+}
+
+/*
+ * Receive a frame from the socket and optionally record the address of the
+ * sender. We verify the buffers are writable and if needed move the
+ * sender address from kernel to user space.
+ */
+int __sys_recvfrom(int fd, void __user *ubuf, size_t size, unsigned int flags,
+ struct sockaddr __user *addr, int __user *addr_len)
+{
+ struct sockaddr_storage address;
+ struct msghdr msg = {
+ /* Save some cycles and don't copy the address if not needed */
+ .msg_name = addr ? (struct sockaddr *)&address : NULL,
+ };
+ struct socket *sock;
+ struct iovec iov;
+ int err, err2;
+ int fput_needed;
+
+ err = import_single_range(ITER_DEST, ubuf, size, &iov, &msg.msg_iter);
+ if (unlikely(err))
+ return err;
+ sock = sockfd_lookup_light(fd, &err, &fput_needed);
+ if (!sock)
+ goto out;
+
+ if (sock->file->f_flags & O_NONBLOCK)
+ flags |= MSG_DONTWAIT;
+ err = sock_recvmsg(sock, &msg, flags);
+
+ if (err >= 0 && addr != NULL) {
+ err2 = move_addr_to_user(&address,
+ msg.msg_namelen, addr, addr_len);
+ if (err2 < 0)
+ err = err2;
+ }
+
+ fput_light(sock->file, fput_needed);
+out:
+ return err;
+}
+
+SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, ubuf, size_t, size,
+ unsigned int, flags, struct sockaddr __user *, addr,
+ int __user *, addr_len)
+{
+ return __sys_recvfrom(fd, ubuf, size, flags, addr, addr_len);
+}
+
+/*
+ * Receive a datagram from a socket.
+ */
+
+SYSCALL_DEFINE4(recv, int, fd, void __user *, ubuf, size_t, size,
+ unsigned int, flags)
+{
+ return __sys_recvfrom(fd, ubuf, size, flags, NULL, NULL);
+}
+
+static bool sock_use_custom_sol_socket(const struct socket *sock)
+{
+ const struct sock *sk = sock->sk;
+
+ /* Use sock->ops->setsockopt() for MPTCP */
+ return IS_ENABLED(CONFIG_MPTCP) &&
+ sk->sk_protocol == IPPROTO_MPTCP &&
+ sk->sk_type == SOCK_STREAM &&
+ (sk->sk_family == AF_INET || sk->sk_family == AF_INET6);
+}
+
+/*
+ * Set a socket option. Because we don't know the option lengths we have
+ * to pass the user mode parameter for the protocols to sort out.
+ */
+int __sys_setsockopt(int fd, int level, int optname, char __user *user_optval,
+ int optlen)
+{
+ sockptr_t optval = USER_SOCKPTR(user_optval);
+ char *kernel_optval = NULL;
+ int err, fput_needed;
+ struct socket *sock;
+
+ if (optlen < 0)
+ return -EINVAL;
+
+ sock = sockfd_lookup_light(fd, &err, &fput_needed);
+ if (!sock)
+ return err;
+
+ err = security_socket_setsockopt(sock, level, optname);
+ if (err)
+ goto out_put;
+
+ if (!in_compat_syscall())
+ err = BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock->sk, &level, &optname,
+ user_optval, &optlen,
+ &kernel_optval);
+ if (err < 0)
+ goto out_put;
+ if (err > 0) {
+ err = 0;
+ goto out_put;
+ }
+
+ if (kernel_optval)
+ optval = KERNEL_SOCKPTR(kernel_optval);
+ if (level == SOL_SOCKET && !sock_use_custom_sol_socket(sock))
+ err = sock_setsockopt(sock, level, optname, optval, optlen);
+ else if (unlikely(!sock->ops->setsockopt))
+ err = -EOPNOTSUPP;
+ else
+ err = sock->ops->setsockopt(sock, level, optname, optval,
+ optlen);
+ kfree(kernel_optval);
+out_put:
+ fput_light(sock->file, fput_needed);
+ return err;
+}
+
+SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
+ char __user *, optval, int, optlen)
+{
+ return __sys_setsockopt(fd, level, optname, optval, optlen);
+}
+
+INDIRECT_CALLABLE_DECLARE(bool tcp_bpf_bypass_getsockopt(int level,
+ int optname));
+
+/*
+ * Get a socket option. Because we don't know the option lengths we have
+ * to pass a user mode parameter for the protocols to sort out.
+ */
+int __sys_getsockopt(int fd, int level, int optname, char __user *optval,
+ int __user *optlen)
+{
+ int err, fput_needed;
+ struct socket *sock;
+ int max_optlen;
+
+ sock = sockfd_lookup_light(fd, &err, &fput_needed);
+ if (!sock)
+ return err;
+
+ err = security_socket_getsockopt(sock, level, optname);
+ if (err)
+ goto out_put;
+
+ if (!in_compat_syscall())
+ max_optlen = BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen);
+
+ if (level == SOL_SOCKET)
+ err = sock_getsockopt(sock, level, optname, optval, optlen);
+ else if (unlikely(!sock->ops->getsockopt))
+ err = -EOPNOTSUPP;
+ else
+ err = sock->ops->getsockopt(sock, level, optname, optval,
+ optlen);
+
+ if (!in_compat_syscall())
+ err = BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock->sk, level, optname,
+ optval, optlen, max_optlen,
+ err);
+out_put:
+ fput_light(sock->file, fput_needed);
+ return err;
+}
+
+SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
+ char __user *, optval, int __user *, optlen)
+{
+ return __sys_getsockopt(fd, level, optname, optval, optlen);
+}
+
+/*
+ * Shutdown a socket.
+ */
+
+int __sys_shutdown_sock(struct socket *sock, int how)
+{
+ int err;
+
+ err = security_socket_shutdown(sock, how);
+ if (!err)
+ err = sock->ops->shutdown(sock, how);
+
+ return err;
+}
+
+int __sys_shutdown(int fd, int how)
+{
+ int err, fput_needed;
+ struct socket *sock;
+
+ sock = sockfd_lookup_light(fd, &err, &fput_needed);
+ if (sock != NULL) {
+ err = __sys_shutdown_sock(sock, how);
+ fput_light(sock->file, fput_needed);
+ }
+ return err;
+}
+
+SYSCALL_DEFINE2(shutdown, int, fd, int, how)
+{
+ return __sys_shutdown(fd, how);
+}
+
+/* A couple of helpful macros for getting the address of the 32/64 bit
+ * fields which are the same type (int / unsigned) on our platforms.
+ */
+#define COMPAT_MSG(msg, member) ((MSG_CMSG_COMPAT & flags) ? &msg##_compat->member : &msg->member)
+#define COMPAT_NAMELEN(msg) COMPAT_MSG(msg, msg_namelen)
+#define COMPAT_FLAGS(msg) COMPAT_MSG(msg, msg_flags)
+
+struct used_address {
+ struct sockaddr_storage name;
+ unsigned int name_len;
+};
+
+int __copy_msghdr(struct msghdr *kmsg,
+ struct user_msghdr *msg,
+ struct sockaddr __user **save_addr)
+{
+ ssize_t err;
+
+ kmsg->msg_control_is_user = true;
+ kmsg->msg_get_inq = 0;
+ kmsg->msg_control_user = msg->msg_control;
+ kmsg->msg_controllen = msg->msg_controllen;
+ kmsg->msg_flags = msg->msg_flags;
+
+ kmsg->msg_namelen = msg->msg_namelen;
+ if (!msg->msg_name)
+ kmsg->msg_namelen = 0;
+
+ if (kmsg->msg_namelen < 0)
+ return -EINVAL;
+
+ if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
+ kmsg->msg_namelen = sizeof(struct sockaddr_storage);
+
+ if (save_addr)
+ *save_addr = msg->msg_name;
+
+ if (msg->msg_name && kmsg->msg_namelen) {
+ if (!save_addr) {
+ err = move_addr_to_kernel(msg->msg_name,
+ kmsg->msg_namelen,
+ kmsg->msg_name);
+ if (err < 0)
+ return err;
+ }
+ } else {
+ kmsg->msg_name = NULL;
+ kmsg->msg_namelen = 0;
+ }
+
+ if (msg->msg_iovlen > UIO_MAXIOV)
+ return -EMSGSIZE;
+
+ kmsg->msg_iocb = NULL;
+ kmsg->msg_ubuf = NULL;
+ return 0;
+}
+
+static int copy_msghdr_from_user(struct msghdr *kmsg,
+ struct user_msghdr __user *umsg,
+ struct sockaddr __user **save_addr,
+ struct iovec **iov)
+{
+ struct user_msghdr msg;
+ ssize_t err;
+
+ if (copy_from_user(&msg, umsg, sizeof(*umsg)))
+ return -EFAULT;
+
+ err = __copy_msghdr(kmsg, &msg, save_addr);
+ if (err)
+ return err;
+
+ err = import_iovec(save_addr ? ITER_DEST : ITER_SOURCE,
+ msg.msg_iov, msg.msg_iovlen,
+ UIO_FASTIOV, iov, &kmsg->msg_iter);
+ return err < 0 ? err : 0;
+}
+
+static int ____sys_sendmsg(struct socket *sock, struct msghdr *msg_sys,
+ unsigned int flags, struct used_address *used_address,
+ unsigned int allowed_msghdr_flags)
+{
+ unsigned char ctl[sizeof(struct cmsghdr) + 20]
+ __aligned(sizeof(__kernel_size_t));
+ /* 20 is size of ipv6_pktinfo */
+ unsigned char *ctl_buf = ctl;
+ int ctl_len;
+ ssize_t err;
+
+ err = -ENOBUFS;
+
+ if (msg_sys->msg_controllen > INT_MAX)
+ goto out;
+ flags |= (msg_sys->msg_flags & allowed_msghdr_flags);
+ ctl_len = msg_sys->msg_controllen;
+ if ((MSG_CMSG_COMPAT & flags) && ctl_len) {
+ err =
+ cmsghdr_from_user_compat_to_kern(msg_sys, sock->sk, ctl,
+ sizeof(ctl));
+ if (err)
+ goto out;
+ ctl_buf = msg_sys->msg_control;
+ ctl_len = msg_sys->msg_controllen;
+ } else if (ctl_len) {
+ BUILD_BUG_ON(sizeof(struct cmsghdr) !=
+ CMSG_ALIGN(sizeof(struct cmsghdr)));
+ if (ctl_len > sizeof(ctl)) {
+ ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL);
+ if (ctl_buf == NULL)
+ goto out;
+ }
+ err = -EFAULT;
+ if (copy_from_user(ctl_buf, msg_sys->msg_control_user, ctl_len))
+ goto out_freectl;
+ msg_sys->msg_control = ctl_buf;
+ msg_sys->msg_control_is_user = false;
+ }
+ flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
+ msg_sys->msg_flags = flags;
+
+ if (sock->file->f_flags & O_NONBLOCK)
+ msg_sys->msg_flags |= MSG_DONTWAIT;
+ /*
+ * If this is sendmmsg() and current destination address is same as
+ * previously succeeded address, omit asking LSM's decision.
+ * used_address->name_len is initialized to UINT_MAX so that the first
+ * destination address never matches.
+ */
+ if (used_address && msg_sys->msg_name &&
+ used_address->name_len == msg_sys->msg_namelen &&
+ !memcmp(&used_address->name, msg_sys->msg_name,
+ used_address->name_len)) {
+ err = sock_sendmsg_nosec(sock, msg_sys);
+ goto out_freectl;
+ }
+ err = __sock_sendmsg(sock, msg_sys);
+ /*
+ * If this is sendmmsg() and sending to current destination address was
+ * successful, remember it.
+ */
+ if (used_address && err >= 0) {
+ used_address->name_len = msg_sys->msg_namelen;
+ if (msg_sys->msg_name)
+ memcpy(&used_address->name, msg_sys->msg_name,
+ used_address->name_len);
+ }
+
+out_freectl:
+ if (ctl_buf != ctl)
+ sock_kfree_s(sock->sk, ctl_buf, ctl_len);
+out:
+ return err;
+}
+
+int sendmsg_copy_msghdr(struct msghdr *msg,
+ struct user_msghdr __user *umsg, unsigned flags,
+ struct iovec **iov)
+{
+ int err;
+
+ if (flags & MSG_CMSG_COMPAT) {
+ struct compat_msghdr __user *msg_compat;
+
+ msg_compat = (struct compat_msghdr __user *) umsg;
+ err = get_compat_msghdr(msg, msg_compat, NULL, iov);
+ } else {
+ err = copy_msghdr_from_user(msg, umsg, NULL, iov);
+ }
+ if (err < 0)
+ return err;
+
+ return 0;
+}
+
+static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,
+ struct msghdr *msg_sys, unsigned int flags,
+ struct used_address *used_address,
+ unsigned int allowed_msghdr_flags)
+{
+ struct sockaddr_storage address;
+ struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
+ ssize_t err;
+
+ msg_sys->msg_name = &address;
+
+ err = sendmsg_copy_msghdr(msg_sys, msg, flags, &iov);
+ if (err < 0)
+ return err;
+
+ err = ____sys_sendmsg(sock, msg_sys, flags, used_address,
+ allowed_msghdr_flags);
+ kfree(iov);
+ return err;
+}
+
+/*
+ * BSD sendmsg interface
+ */
+long __sys_sendmsg_sock(struct socket *sock, struct msghdr *msg,
+ unsigned int flags)
+{
+ return ____sys_sendmsg(sock, msg, flags, NULL, 0);
+}
+
+long __sys_sendmsg(int fd, struct user_msghdr __user *msg, unsigned int flags,
+ bool forbid_cmsg_compat)
+{
+ int fput_needed, err;
+ struct msghdr msg_sys;
+ struct socket *sock;
+
+ if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
+ return -EINVAL;
+
+ sock = sockfd_lookup_light(fd, &err, &fput_needed);
+ if (!sock)
+ goto out;
+
+ err = ___sys_sendmsg(sock, msg, &msg_sys, flags, NULL, 0);
+
+ fput_light(sock->file, fput_needed);
+out:
+ return err;
+}
+
+SYSCALL_DEFINE3(sendmsg, int, fd, struct user_msghdr __user *, msg, unsigned int, flags)
+{
+ return __sys_sendmsg(fd, msg, flags, true);
+}
+
+/*
+ * Linux sendmmsg interface
+ */
+
+int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
+ unsigned int flags, bool forbid_cmsg_compat)
+{
+ int fput_needed, err, datagrams;
+ struct socket *sock;
+ struct mmsghdr __user *entry;
+ struct compat_mmsghdr __user *compat_entry;
+ struct msghdr msg_sys;
+ struct used_address used_address;
+ unsigned int oflags = flags;
+
+ if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
+ return -EINVAL;
+
+ if (vlen > UIO_MAXIOV)
+ vlen = UIO_MAXIOV;
+
+ datagrams = 0;
+
+ sock = sockfd_lookup_light(fd, &err, &fput_needed);
+ if (!sock)
+ return err;
+
+ used_address.name_len = UINT_MAX;
+ entry = mmsg;
+ compat_entry = (struct compat_mmsghdr __user *)mmsg;
+ err = 0;
+ flags |= MSG_BATCH;
+
+ while (datagrams < vlen) {
+ if (datagrams == vlen - 1)
+ flags = oflags;
+
+ if (MSG_CMSG_COMPAT & flags) {
+ err = ___sys_sendmsg(sock, (struct user_msghdr __user *)compat_entry,
+ &msg_sys, flags, &used_address, MSG_EOR);
+ if (err < 0)
+ break;
+ err = __put_user(err, &compat_entry->msg_len);
+ ++compat_entry;
+ } else {
+ err = ___sys_sendmsg(sock,
+ (struct user_msghdr __user *)entry,
+ &msg_sys, flags, &used_address, MSG_EOR);
+ if (err < 0)
+ break;
+ err = put_user(err, &entry->msg_len);
+ ++entry;
+ }
+
+ if (err)
+ break;
+ ++datagrams;
+ if (msg_data_left(&msg_sys))
+ break;
+ cond_resched();
+ }
+
+ fput_light(sock->file, fput_needed);
+
+ /* We only return an error if no datagrams were able to be sent */
+ if (datagrams != 0)
+ return datagrams;
+
+ return err;
+}
+
+SYSCALL_DEFINE4(sendmmsg, int, fd, struct mmsghdr __user *, mmsg,
+ unsigned int, vlen, unsigned int, flags)
+{
+ return __sys_sendmmsg(fd, mmsg, vlen, flags, true);
+}
+
+int recvmsg_copy_msghdr(struct msghdr *msg,
+ struct user_msghdr __user *umsg, unsigned flags,
+ struct sockaddr __user **uaddr,
+ struct iovec **iov)
+{
+ ssize_t err;
+
+ if (MSG_CMSG_COMPAT & flags) {
+ struct compat_msghdr __user *msg_compat;
+
+ msg_compat = (struct compat_msghdr __user *) umsg;
+ err = get_compat_msghdr(msg, msg_compat, uaddr, iov);
+ } else {
+ err = copy_msghdr_from_user(msg, umsg, uaddr, iov);
+ }
+ if (err < 0)
+ return err;
+
+ return 0;
+}
+
+static int ____sys_recvmsg(struct socket *sock, struct msghdr *msg_sys,
+ struct user_msghdr __user *msg,
+ struct sockaddr __user *uaddr,
+ unsigned int flags, int nosec)
+{
+ struct compat_msghdr __user *msg_compat =
+ (struct compat_msghdr __user *) msg;
+ int __user *uaddr_len = COMPAT_NAMELEN(msg);
+ struct sockaddr_storage addr;
+ unsigned long cmsg_ptr;
+ int len;
+ ssize_t err;
+
+ msg_sys->msg_name = &addr;
+ cmsg_ptr = (unsigned long)msg_sys->msg_control;
+ msg_sys->msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
+
+ /* We assume all kernel code knows the size of sockaddr_storage */
+ msg_sys->msg_namelen = 0;
+
+ if (sock->file->f_flags & O_NONBLOCK)
+ flags |= MSG_DONTWAIT;
+
+ if (unlikely(nosec))
+ err = sock_recvmsg_nosec(sock, msg_sys, flags);
+ else
+ err = sock_recvmsg(sock, msg_sys, flags);
+
+ if (err < 0)
+ goto out;
+ len = err;
+
+ if (uaddr != NULL) {
+ err = move_addr_to_user(&addr,
+ msg_sys->msg_namelen, uaddr,
+ uaddr_len);
+ if (err < 0)
+ goto out;
+ }
+ err = __put_user((msg_sys->msg_flags & ~MSG_CMSG_COMPAT),
+ COMPAT_FLAGS(msg));
+ if (err)
+ goto out;
+ if (MSG_CMSG_COMPAT & flags)
+ err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
+ &msg_compat->msg_controllen);
+ else
+ err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
+ &msg->msg_controllen);
+ if (err)
+ goto out;
+ err = len;
+out:
+ return err;
+}
+
+static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg,
+ struct msghdr *msg_sys, unsigned int flags, int nosec)
+{
+ struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
+ /* user mode address pointers */
+ struct sockaddr __user *uaddr;
+ ssize_t err;
+
+ err = recvmsg_copy_msghdr(msg_sys, msg, flags, &uaddr, &iov);
+ if (err < 0)
+ return err;
+
+ err = ____sys_recvmsg(sock, msg_sys, msg, uaddr, flags, nosec);
+ kfree(iov);
+ return err;
+}
+
+/*
+ * BSD recvmsg interface
+ */
+
+long __sys_recvmsg_sock(struct socket *sock, struct msghdr *msg,
+ struct user_msghdr __user *umsg,
+ struct sockaddr __user *uaddr, unsigned int flags)
+{
+ return ____sys_recvmsg(sock, msg, umsg, uaddr, flags, 0);
+}
+
+long __sys_recvmsg(int fd, struct user_msghdr __user *msg, unsigned int flags,
+ bool forbid_cmsg_compat)
+{
+ int fput_needed, err;
+ struct msghdr msg_sys;
+ struct socket *sock;
+
+ if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
+ return -EINVAL;
+
+ sock = sockfd_lookup_light(fd, &err, &fput_needed);
+ if (!sock)
+ goto out;
+
+ err = ___sys_recvmsg(sock, msg, &msg_sys, flags, 0);
+
+ fput_light(sock->file, fput_needed);
+out:
+ return err;
+}
+
+SYSCALL_DEFINE3(recvmsg, int, fd, struct user_msghdr __user *, msg,
+ unsigned int, flags)
+{
+ return __sys_recvmsg(fd, msg, flags, true);
+}
+
+/*
+ * Linux recvmmsg interface
+ */
+
+static int do_recvmmsg(int fd, struct mmsghdr __user *mmsg,
+ unsigned int vlen, unsigned int flags,
+ struct timespec64 *timeout)
+{
+ int fput_needed, err, datagrams;
+ struct socket *sock;
+ struct mmsghdr __user *entry;
+ struct compat_mmsghdr __user *compat_entry;
+ struct msghdr msg_sys;
+ struct timespec64 end_time;
+ struct timespec64 timeout64;
+
+ if (timeout &&
+ poll_select_set_timeout(&end_time, timeout->tv_sec,
+ timeout->tv_nsec))
+ return -EINVAL;
+
+ datagrams = 0;
+
+ sock = sockfd_lookup_light(fd, &err, &fput_needed);
+ if (!sock)
+ return err;
+
+ if (likely(!(flags & MSG_ERRQUEUE))) {
+ err = sock_error(sock->sk);
+ if (err) {
+ datagrams = err;
+ goto out_put;
+ }
+ }
+
+ entry = mmsg;
+ compat_entry = (struct compat_mmsghdr __user *)mmsg;
+
+ while (datagrams < vlen) {
+ /*
+ * No need to ask LSM for more than the first datagram.
+ */
+ if (MSG_CMSG_COMPAT & flags) {
+ err = ___sys_recvmsg(sock, (struct user_msghdr __user *)compat_entry,
+ &msg_sys, flags & ~MSG_WAITFORONE,
+ datagrams);
+ if (err < 0)
+ break;
+ err = __put_user(err, &compat_entry->msg_len);
+ ++compat_entry;
+ } else {
+ err = ___sys_recvmsg(sock,
+ (struct user_msghdr __user *)entry,
+ &msg_sys, flags & ~MSG_WAITFORONE,
+ datagrams);
+ if (err < 0)
+ break;
+ err = put_user(err, &entry->msg_len);
+ ++entry;
+ }
+
+ if (err)
+ break;
+ ++datagrams;
+
+ /* MSG_WAITFORONE turns on MSG_DONTWAIT after one packet */
+ if (flags & MSG_WAITFORONE)
+ flags |= MSG_DONTWAIT;
+
+ if (timeout) {
+ ktime_get_ts64(&timeout64);
+ *timeout = timespec64_sub(end_time, timeout64);
+ if (timeout->tv_sec < 0) {
+ timeout->tv_sec = timeout->tv_nsec = 0;
+ break;
+ }
+
+ /* Timeout, return less than vlen datagrams */
+ if (timeout->tv_nsec == 0 && timeout->tv_sec == 0)
+ break;
+ }
+
+ /* Out of band data, return right away */
+ if (msg_sys.msg_flags & MSG_OOB)
+ break;
+ cond_resched();
+ }
+
+ if (err == 0)
+ goto out_put;
+
+ if (datagrams == 0) {
+ datagrams = err;
+ goto out_put;
+ }
+
+ /*
+ * We may return less entries than requested (vlen) if the
+ * sock is non block and there aren't enough datagrams...
+ */
+ if (err != -EAGAIN) {
+ /*
+ * ... or if recvmsg returns an error after we
+ * received some datagrams, where we record the
+ * error to return on the next call or if the
+ * app asks about it using getsockopt(SO_ERROR).
+ */
+ WRITE_ONCE(sock->sk->sk_err, -err);
+ }
+out_put:
+ fput_light(sock->file, fput_needed);
+
+ return datagrams;
+}
+
+int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg,
+ unsigned int vlen, unsigned int flags,
+ struct __kernel_timespec __user *timeout,
+ struct old_timespec32 __user *timeout32)
+{
+ int datagrams;
+ struct timespec64 timeout_sys;
+
+ if (timeout && get_timespec64(&timeout_sys, timeout))
+ return -EFAULT;
+
+ if (timeout32 && get_old_timespec32(&timeout_sys, timeout32))
+ return -EFAULT;
+
+ if (!timeout && !timeout32)
+ return do_recvmmsg(fd, mmsg, vlen, flags, NULL);
+
+ datagrams = do_recvmmsg(fd, mmsg, vlen, flags, &timeout_sys);
+
+ if (datagrams <= 0)
+ return datagrams;
+
+ if (timeout && put_timespec64(&timeout_sys, timeout))
+ datagrams = -EFAULT;
+
+ if (timeout32 && put_old_timespec32(&timeout_sys, timeout32))
+ datagrams = -EFAULT;
+
+ return datagrams;
+}
+
+SYSCALL_DEFINE5(recvmmsg, int, fd, struct mmsghdr __user *, mmsg,
+ unsigned int, vlen, unsigned int, flags,
+ struct __kernel_timespec __user *, timeout)
+{
+ if (flags & MSG_CMSG_COMPAT)
+ return -EINVAL;
+
+ return __sys_recvmmsg(fd, mmsg, vlen, flags, timeout, NULL);
+}
+
+#ifdef CONFIG_COMPAT_32BIT_TIME
+SYSCALL_DEFINE5(recvmmsg_time32, int, fd, struct mmsghdr __user *, mmsg,
+ unsigned int, vlen, unsigned int, flags,
+ struct old_timespec32 __user *, timeout)
+{
+ if (flags & MSG_CMSG_COMPAT)
+ return -EINVAL;
+
+ return __sys_recvmmsg(fd, mmsg, vlen, flags, NULL, timeout);
+}
+#endif
+
+#ifdef __ARCH_WANT_SYS_SOCKETCALL
+/* Argument list sizes for sys_socketcall */
+#define AL(x) ((x) * sizeof(unsigned long))
+static const unsigned char nargs[21] = {
+ AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
+ AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
+ AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
+ AL(4), AL(5), AL(4)
+};
+
+#undef AL
+
+/*
+ * System call vectors.
+ *
+ * Argument checking cleaned up. Saved 20% in size.
+ * This function doesn't need to set the kernel lock because
+ * it is set by the callees.
+ */
+
+SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
+{
+ unsigned long a[AUDITSC_ARGS];
+ unsigned long a0, a1;
+ int err;
+ unsigned int len;
+
+ if (call < 1 || call > SYS_SENDMMSG)
+ return -EINVAL;
+ call = array_index_nospec(call, SYS_SENDMMSG + 1);
+
+ len = nargs[call];
+ if (len > sizeof(a))
+ return -EINVAL;
+
+ /* copy_from_user should be SMP safe. */
+ if (copy_from_user(a, args, len))
+ return -EFAULT;
+
+ err = audit_socketcall(nargs[call] / sizeof(unsigned long), a);
+ if (err)
+ return err;
+
+ a0 = a[0];
+ a1 = a[1];
+
+ switch (call) {
+ case SYS_SOCKET:
+ err = __sys_socket(a0, a1, a[2]);
+ break;
+ case SYS_BIND:
+ err = __sys_bind(a0, (struct sockaddr __user *)a1, a[2]);
+ break;
+ case SYS_CONNECT:
+ err = __sys_connect(a0, (struct sockaddr __user *)a1, a[2]);
+ break;
+ case SYS_LISTEN:
+ err = __sys_listen(a0, a1);
+ break;
+ case SYS_ACCEPT:
+ err = __sys_accept4(a0, (struct sockaddr __user *)a1,
+ (int __user *)a[2], 0);
+ break;
+ case SYS_GETSOCKNAME:
+ err =
+ __sys_getsockname(a0, (struct sockaddr __user *)a1,
+ (int __user *)a[2]);
+ break;
+ case SYS_GETPEERNAME:
+ err =
+ __sys_getpeername(a0, (struct sockaddr __user *)a1,
+ (int __user *)a[2]);
+ break;
+ case SYS_SOCKETPAIR:
+ err = __sys_socketpair(a0, a1, a[2], (int __user *)a[3]);
+ break;
+ case SYS_SEND:
+ err = __sys_sendto(a0, (void __user *)a1, a[2], a[3],
+ NULL, 0);
+ break;
+ case SYS_SENDTO:
+ err = __sys_sendto(a0, (void __user *)a1, a[2], a[3],
+ (struct sockaddr __user *)a[4], a[5]);
+ break;
+ case SYS_RECV:
+ err = __sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
+ NULL, NULL);
+ break;
+ case SYS_RECVFROM:
+ err = __sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
+ (struct sockaddr __user *)a[4],
+ (int __user *)a[5]);
+ break;
+ case SYS_SHUTDOWN:
+ err = __sys_shutdown(a0, a1);
+ break;
+ case SYS_SETSOCKOPT:
+ err = __sys_setsockopt(a0, a1, a[2], (char __user *)a[3],
+ a[4]);
+ break;
+ case SYS_GETSOCKOPT:
+ err =
+ __sys_getsockopt(a0, a1, a[2], (char __user *)a[3],
+ (int __user *)a[4]);
+ break;
+ case SYS_SENDMSG:
+ err = __sys_sendmsg(a0, (struct user_msghdr __user *)a1,
+ a[2], true);
+ break;
+ case SYS_SENDMMSG:
+ err = __sys_sendmmsg(a0, (struct mmsghdr __user *)a1, a[2],
+ a[3], true);
+ break;
+ case SYS_RECVMSG:
+ err = __sys_recvmsg(a0, (struct user_msghdr __user *)a1,
+ a[2], true);
+ break;
+ case SYS_RECVMMSG:
+ if (IS_ENABLED(CONFIG_64BIT))
+ err = __sys_recvmmsg(a0, (struct mmsghdr __user *)a1,
+ a[2], a[3],
+ (struct __kernel_timespec __user *)a[4],
+ NULL);
+ else
+ err = __sys_recvmmsg(a0, (struct mmsghdr __user *)a1,
+ a[2], a[3], NULL,
+ (struct old_timespec32 __user *)a[4]);
+ break;
+ case SYS_ACCEPT4:
+ err = __sys_accept4(a0, (struct sockaddr __user *)a1,
+ (int __user *)a[2], a[3]);
+ break;
+ default:
+ err = -EINVAL;
+ break;
+ }
+ return err;
+}
+
+#endif /* __ARCH_WANT_SYS_SOCKETCALL */
+
+/**
+ * sock_register - add a socket protocol handler
+ * @ops: description of protocol
+ *
+ * This function is called by a protocol handler that wants to
+ * advertise its address family, and have it linked into the
+ * socket interface. The value ops->family corresponds to the
+ * socket system call protocol family.
+ */
+int sock_register(const struct net_proto_family *ops)
+{
+ int err;
+
+ if (ops->family >= NPROTO) {
+ pr_crit("protocol %d >= NPROTO(%d)\n", ops->family, NPROTO);
+ return -ENOBUFS;
+ }
+
+ spin_lock(&net_family_lock);
+ if (rcu_dereference_protected(net_families[ops->family],
+ lockdep_is_held(&net_family_lock)))
+ err = -EEXIST;
+ else {
+ rcu_assign_pointer(net_families[ops->family], ops);
+ err = 0;
+ }
+ spin_unlock(&net_family_lock);
+
+ pr_info("NET: Registered %s protocol family\n", pf_family_names[ops->family]);
+ return err;
+}
+EXPORT_SYMBOL(sock_register);
+
+/**
+ * sock_unregister - remove a protocol handler
+ * @family: protocol family to remove
+ *
+ * This function is called by a protocol handler that wants to
+ * remove its address family, and have it unlinked from the
+ * new socket creation.
+ *
+ * If protocol handler is a module, then it can use module reference
+ * counts to protect against new references. If protocol handler is not
+ * a module then it needs to provide its own protection in
+ * the ops->create routine.
+ */
+void sock_unregister(int family)
+{
+ BUG_ON(family < 0 || family >= NPROTO);
+
+ spin_lock(&net_family_lock);
+ RCU_INIT_POINTER(net_families[family], NULL);
+ spin_unlock(&net_family_lock);
+
+ synchronize_rcu();
+
+ pr_info("NET: Unregistered %s protocol family\n", pf_family_names[family]);
+}
+EXPORT_SYMBOL(sock_unregister);
+
+bool sock_is_registered(int family)
+{
+ return family < NPROTO && rcu_access_pointer(net_families[family]);
+}
+
+static int __init sock_init(void)
+{
+ int err;
+ /*
+ * Initialize the network sysctl infrastructure.
+ */
+ err = net_sysctl_init();
+ if (err)
+ goto out;
+
+ /*
+ * Initialize skbuff SLAB cache
+ */
+ skb_init();
+
+ /*
+ * Initialize the protocols module.
+ */
+
+ init_inodecache();
+
+ err = register_filesystem(&sock_fs_type);
+ if (err)
+ goto out;
+ sock_mnt = kern_mount(&sock_fs_type);
+ if (IS_ERR(sock_mnt)) {
+ err = PTR_ERR(sock_mnt);
+ goto out_mount;
+ }
+
+ /* The real protocol initialization is performed in later initcalls.
+ */
+
+#ifdef CONFIG_NETFILTER
+ err = netfilter_init();
+ if (err)
+ goto out;
+#endif
+
+ ptp_classifier_init();
+
+out:
+ return err;
+
+out_mount:
+ unregister_filesystem(&sock_fs_type);
+ goto out;
+}
+
+core_initcall(sock_init); /* early initcall */
+
+#ifdef CONFIG_PROC_FS
+void socket_seq_show(struct seq_file *seq)
+{
+ seq_printf(seq, "sockets: used %d\n",
+ sock_inuse_get(seq->private));
+}
+#endif /* CONFIG_PROC_FS */
+
+/* Handle the fact that while struct ifreq has the same *layout* on
+ * 32/64 for everything but ifreq::ifru_ifmap and ifreq::ifru_data,
+ * which are handled elsewhere, it still has different *size* due to
+ * ifreq::ifru_ifmap (which is 16 bytes on 32 bit, 24 bytes on 64-bit,
+ * resulting in struct ifreq being 32 and 40 bytes respectively).
+ * As a result, if the struct happens to be at the end of a page and
+ * the next page isn't readable/writable, we get a fault. To prevent
+ * that, copy back and forth to the full size.
+ */
+int get_user_ifreq(struct ifreq *ifr, void __user **ifrdata, void __user *arg)
+{
+ if (in_compat_syscall()) {
+ struct compat_ifreq *ifr32 = (struct compat_ifreq *)ifr;
+
+ memset(ifr, 0, sizeof(*ifr));
+ if (copy_from_user(ifr32, arg, sizeof(*ifr32)))
+ return -EFAULT;
+
+ if (ifrdata)
+ *ifrdata = compat_ptr(ifr32->ifr_data);
+
+ return 0;
+ }
+
+ if (copy_from_user(ifr, arg, sizeof(*ifr)))
+ return -EFAULT;
+
+ if (ifrdata)
+ *ifrdata = ifr->ifr_data;
+
+ return 0;
+}
+EXPORT_SYMBOL(get_user_ifreq);
+
+int put_user_ifreq(struct ifreq *ifr, void __user *arg)
+{
+ size_t size = sizeof(*ifr);
+
+ if (in_compat_syscall())
+ size = sizeof(struct compat_ifreq);
+
+ if (copy_to_user(arg, ifr, size))
+ return -EFAULT;
+
+ return 0;
+}
+EXPORT_SYMBOL(put_user_ifreq);
+
+#ifdef CONFIG_COMPAT
+static int compat_siocwandev(struct net *net, struct compat_ifreq __user *uifr32)
+{
+ compat_uptr_t uptr32;
+ struct ifreq ifr;
+ void __user *saved;
+ int err;
+
+ if (get_user_ifreq(&ifr, NULL, uifr32))
+ return -EFAULT;
+
+ if (get_user(uptr32, &uifr32->ifr_settings.ifs_ifsu))
+ return -EFAULT;
+
+ saved = ifr.ifr_settings.ifs_ifsu.raw_hdlc;
+ ifr.ifr_settings.ifs_ifsu.raw_hdlc = compat_ptr(uptr32);
+
+ err = dev_ioctl(net, SIOCWANDEV, &ifr, NULL, NULL);
+ if (!err) {
+ ifr.ifr_settings.ifs_ifsu.raw_hdlc = saved;
+ if (put_user_ifreq(&ifr, uifr32))
+ err = -EFAULT;
+ }
+ return err;
+}
+
+/* Handle ioctls that use ifreq::ifr_data and just need struct ifreq converted */
+static int compat_ifr_data_ioctl(struct net *net, unsigned int cmd,
+ struct compat_ifreq __user *u_ifreq32)
+{
+ struct ifreq ifreq;
+ void __user *data;
+
+ if (!is_socket_ioctl_cmd(cmd))
+ return -ENOTTY;
+ if (get_user_ifreq(&ifreq, &data, u_ifreq32))
+ return -EFAULT;
+ ifreq.ifr_data = data;
+
+ return dev_ioctl(net, cmd, &ifreq, data, NULL);
+}
+
+static int compat_sock_ioctl_trans(struct file *file, struct socket *sock,
+ unsigned int cmd, unsigned long arg)
+{
+ void __user *argp = compat_ptr(arg);
+ struct sock *sk = sock->sk;
+ struct net *net = sock_net(sk);
+
+ if (cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15))
+ return sock_ioctl(file, cmd, (unsigned long)argp);
+
+ switch (cmd) {
+ case SIOCWANDEV:
+ return compat_siocwandev(net, argp);
+ case SIOCGSTAMP_OLD:
+ case SIOCGSTAMPNS_OLD:
+ if (!sock->ops->gettstamp)
+ return -ENOIOCTLCMD;
+ return sock->ops->gettstamp(sock, argp, cmd == SIOCGSTAMP_OLD,
+ !COMPAT_USE_64BIT_TIME);
+
+ case SIOCETHTOOL:
+ case SIOCBONDSLAVEINFOQUERY:
+ case SIOCBONDINFOQUERY:
+ case SIOCSHWTSTAMP:
+ case SIOCGHWTSTAMP:
+ return compat_ifr_data_ioctl(net, cmd, argp);
+
+ case FIOSETOWN:
+ case SIOCSPGRP:
+ case FIOGETOWN:
+ case SIOCGPGRP:
+ case SIOCBRADDBR:
+ case SIOCBRDELBR:
+ case SIOCGIFVLAN:
+ case SIOCSIFVLAN:
+ case SIOCGSKNS:
+ case SIOCGSTAMP_NEW:
+ case SIOCGSTAMPNS_NEW:
+ case SIOCGIFCONF:
+ case SIOCSIFBR:
+ case SIOCGIFBR:
+ return sock_ioctl(file, cmd, arg);
+
+ case SIOCGIFFLAGS:
+ case SIOCSIFFLAGS:
+ case SIOCGIFMAP:
+ case SIOCSIFMAP:
+ case SIOCGIFMETRIC:
+ case SIOCSIFMETRIC:
+ case SIOCGIFMTU:
+ case SIOCSIFMTU:
+ case SIOCGIFMEM:
+ case SIOCSIFMEM:
+ case SIOCGIFHWADDR:
+ case SIOCSIFHWADDR:
+ case SIOCADDMULTI:
+ case SIOCDELMULTI:
+ case SIOCGIFINDEX:
+ case SIOCGIFADDR:
+ case SIOCSIFADDR:
+ case SIOCSIFHWBROADCAST:
+ case SIOCDIFADDR:
+ case SIOCGIFBRDADDR:
+ case SIOCSIFBRDADDR:
+ case SIOCGIFDSTADDR:
+ case SIOCSIFDSTADDR:
+ case SIOCGIFNETMASK:
+ case SIOCSIFNETMASK:
+ case SIOCSIFPFLAGS:
+ case SIOCGIFPFLAGS:
+ case SIOCGIFTXQLEN:
+ case SIOCSIFTXQLEN:
+ case SIOCBRADDIF:
+ case SIOCBRDELIF:
+ case SIOCGIFNAME:
+ case SIOCSIFNAME:
+ case SIOCGMIIPHY:
+ case SIOCGMIIREG:
+ case SIOCSMIIREG:
+ case SIOCBONDENSLAVE:
+ case SIOCBONDRELEASE:
+ case SIOCBONDSETHWADDR:
+ case SIOCBONDCHANGEACTIVE:
+ case SIOCSARP:
+ case SIOCGARP:
+ case SIOCDARP:
+ case SIOCOUTQ:
+ case SIOCOUTQNSD:
+ case SIOCATMARK:
+ return sock_do_ioctl(net, sock, cmd, arg);
+ }
+
+ return -ENOIOCTLCMD;
+}
+
+static long compat_sock_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ struct socket *sock = file->private_data;
+ int ret = -ENOIOCTLCMD;
+ struct sock *sk;
+ struct net *net;
+
+ sk = sock->sk;
+ net = sock_net(sk);
+
+ if (sock->ops->compat_ioctl)
+ ret = sock->ops->compat_ioctl(sock, cmd, arg);
+
+ if (ret == -ENOIOCTLCMD &&
+ (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST))
+ ret = compat_wext_handle_ioctl(net, cmd, arg);
+
+ if (ret == -ENOIOCTLCMD)
+ ret = compat_sock_ioctl_trans(file, sock, cmd, arg);
+
+ return ret;
+}
+#endif
+
+/**
+ * kernel_bind - bind an address to a socket (kernel space)
+ * @sock: socket
+ * @addr: address
+ * @addrlen: length of address
+ *
+ * Returns 0 or an error.
+ */
+
+int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
+{
+ struct sockaddr_storage address;
+
+ memcpy(&address, addr, addrlen);
+
+ return sock->ops->bind(sock, (struct sockaddr *)&address, addrlen);
+}
+EXPORT_SYMBOL(kernel_bind);
+
+/**
+ * kernel_listen - move socket to listening state (kernel space)
+ * @sock: socket
+ * @backlog: pending connections queue size
+ *
+ * Returns 0 or an error.
+ */
+
+int kernel_listen(struct socket *sock, int backlog)
+{
+ return sock->ops->listen(sock, backlog);
+}
+EXPORT_SYMBOL(kernel_listen);
+
+/**
+ * kernel_accept - accept a connection (kernel space)
+ * @sock: listening socket
+ * @newsock: new connected socket
+ * @flags: flags
+ *
+ * @flags must be SOCK_CLOEXEC, SOCK_NONBLOCK or 0.
+ * If it fails, @newsock is guaranteed to be %NULL.
+ * Returns 0 or an error.
+ */
+
+int kernel_accept(struct socket *sock, struct socket **newsock, int flags)
+{
+ struct sock *sk = sock->sk;
+ int err;
+
+ err = sock_create_lite(sk->sk_family, sk->sk_type, sk->sk_protocol,
+ newsock);
+ if (err < 0)
+ goto done;
+
+ err = sock->ops->accept(sock, *newsock, flags, true);
+ if (err < 0) {
+ sock_release(*newsock);
+ *newsock = NULL;
+ goto done;
+ }
+
+ (*newsock)->ops = sock->ops;
+ __module_get((*newsock)->ops->owner);
+
+done:
+ return err;
+}
+EXPORT_SYMBOL(kernel_accept);
+
+/**
+ * kernel_connect - connect a socket (kernel space)
+ * @sock: socket
+ * @addr: address
+ * @addrlen: address length
+ * @flags: flags (O_NONBLOCK, ...)
+ *
+ * For datagram sockets, @addr is the address to which datagrams are sent
+ * by default, and the only address from which datagrams are received.
+ * For stream sockets, attempts to connect to @addr.
+ * Returns 0 or an error code.
+ */
+
+int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
+ int flags)
+{
+ struct sockaddr_storage address;
+
+ memcpy(&address, addr, addrlen);
+
+ return sock->ops->connect(sock, (struct sockaddr *)&address, addrlen, flags);
+}
+EXPORT_SYMBOL(kernel_connect);
+
+/**
+ * kernel_getsockname - get the address which the socket is bound (kernel space)
+ * @sock: socket
+ * @addr: address holder
+ *
+ * Fills the @addr pointer with the address which the socket is bound.
+ * Returns the length of the address in bytes or an error code.
+ */
+
+int kernel_getsockname(struct socket *sock, struct sockaddr *addr)
+{
+ return sock->ops->getname(sock, addr, 0);
+}
+EXPORT_SYMBOL(kernel_getsockname);
+
+/**
+ * kernel_getpeername - get the address which the socket is connected (kernel space)
+ * @sock: socket
+ * @addr: address holder
+ *
+ * Fills the @addr pointer with the address which the socket is connected.
+ * Returns the length of the address in bytes or an error code.
+ */
+
+int kernel_getpeername(struct socket *sock, struct sockaddr *addr)
+{
+ return sock->ops->getname(sock, addr, 1);
+}
+EXPORT_SYMBOL(kernel_getpeername);
+
+/**
+ * kernel_sendpage - send a &page through a socket (kernel space)
+ * @sock: socket
+ * @page: page
+ * @offset: page offset
+ * @size: total size in bytes
+ * @flags: flags (MSG_DONTWAIT, ...)
+ *
+ * Returns the total amount sent in bytes or an error.
+ */
+
+int kernel_sendpage(struct socket *sock, struct page *page, int offset,
+ size_t size, int flags)
+{
+ if (sock->ops->sendpage) {
+ /* Warn in case the improper page to zero-copy send */
+ WARN_ONCE(!sendpage_ok(page), "improper page for zero-copy send");
+ return sock->ops->sendpage(sock, page, offset, size, flags);
+ }
+ return sock_no_sendpage(sock, page, offset, size, flags);
+}
+EXPORT_SYMBOL(kernel_sendpage);
+
+/**
+ * kernel_sendpage_locked - send a &page through the locked sock (kernel space)
+ * @sk: sock
+ * @page: page
+ * @offset: page offset
+ * @size: total size in bytes
+ * @flags: flags (MSG_DONTWAIT, ...)
+ *
+ * Returns the total amount sent in bytes or an error.
+ * Caller must hold @sk.
+ */
+
+int kernel_sendpage_locked(struct sock *sk, struct page *page, int offset,
+ size_t size, int flags)
+{
+ struct socket *sock = sk->sk_socket;
+
+ if (sock->ops->sendpage_locked)
+ return sock->ops->sendpage_locked(sk, page, offset, size,
+ flags);
+
+ return sock_no_sendpage_locked(sk, page, offset, size, flags);
+}
+EXPORT_SYMBOL(kernel_sendpage_locked);
+
+/**
+ * kernel_sock_shutdown - shut down part of a full-duplex connection (kernel space)
+ * @sock: socket
+ * @how: connection part
+ *
+ * Returns 0 or an error.
+ */
+
+int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how)
+{
+ return sock->ops->shutdown(sock, how);
+}
+EXPORT_SYMBOL(kernel_sock_shutdown);
+
+/**
+ * kernel_sock_ip_overhead - returns the IP overhead imposed by a socket
+ * @sk: socket
+ *
+ * This routine returns the IP overhead imposed by a socket i.e.
+ * the length of the underlying IP header, depending on whether
+ * this is an IPv4 or IPv6 socket and the length from IP options turned
+ * on at the socket. Assumes that the caller has a lock on the socket.
+ */
+
+u32 kernel_sock_ip_overhead(struct sock *sk)
+{
+ struct inet_sock *inet;
+ struct ip_options_rcu *opt;
+ u32 overhead = 0;
+#if IS_ENABLED(CONFIG_IPV6)
+ struct ipv6_pinfo *np;
+ struct ipv6_txoptions *optv6 = NULL;
+#endif /* IS_ENABLED(CONFIG_IPV6) */
+
+ if (!sk)
+ return overhead;
+
+ switch (sk->sk_family) {
+ case AF_INET:
+ inet = inet_sk(sk);
+ overhead += sizeof(struct iphdr);
+ opt = rcu_dereference_protected(inet->inet_opt,
+ sock_owned_by_user(sk));
+ if (opt)
+ overhead += opt->opt.optlen;
+ return overhead;
+#if IS_ENABLED(CONFIG_IPV6)
+ case AF_INET6:
+ np = inet6_sk(sk);
+ overhead += sizeof(struct ipv6hdr);
+ if (np)
+ optv6 = rcu_dereference_protected(np->opt,
+ sock_owned_by_user(sk));
+ if (optv6)
+ overhead += (optv6->opt_flen + optv6->opt_nflen);
+ return overhead;
+#endif /* IS_ENABLED(CONFIG_IPV6) */
+ default: /* Returns 0 overhead if the socket is not ipv4 or ipv6 */
+ return overhead;
+ }
+}
+EXPORT_SYMBOL(kernel_sock_ip_overhead);