diff options
Diffstat (limited to 'net/socket.c')
| -rw-r--r-- | net/socket.c | 3697 |
1 files changed, 3697 insertions, 0 deletions
diff --git a/net/socket.c b/net/socket.c new file mode 100644 index 0000000000..8d83c4bb16 --- /dev/null +++ b/net/socket.c @@ -0,0 +1,3697 @@ +// 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/splice.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/io_uring.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> +#include <trace/events/sock.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_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; + const struct proto_ops *ops = READ_ONCE(sock->ops); + + if (ops->show_fdinfo) + 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 + .uring_cmd = io_uring_cmd_sock, + .mmap = sock_mmap, + .release = sock_close, + .fasync = sock_fasync, + .splice_write = splice_to_socket, + .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 mnt_idmap *idmap, + 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; + } + + file->f_mode |= FMODE_NOWAIT; + 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 mnt_idmap *idmap, + struct dentry *dentry, struct iattr *iattr) +{ + int err = simple_setattr(&nop_mnt_idmap, 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) +{ + const struct proto_ops *ops = READ_ONCE(sock->ops); + + if (ops) { + struct module *owner = ops->owner; + + if (inode) + inode_lock(inode); + 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 noinline void call_trace_sock_send_length(struct sock *sk, int ret, + int flags) +{ + trace_sock_send_length(sk, ret, 0); +} + +static inline int sock_sendmsg_nosec(struct socket *sock, struct msghdr *msg) +{ + int ret = INDIRECT_CALL_INET(READ_ONCE(sock->ops)->sendmsg, inet6_sendmsg, + inet_sendmsg, sock, msg, + msg_data_left(msg)); + BUG_ON(ret == -EIOCBQUEUED); + + if (trace_sock_send_length_enabled()) + call_trace_sock_send_length(sock->sk, ret, 0); + 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; + const struct proto_ops *ops = READ_ONCE(sock->ops); + + if (!ops->sendmsg_locked) + return sock_no_sendmsg_locked(sk, msg, size); + + iov_iter_kvec(&msg->msg_iter, ITER_SOURCE, vec, num, size); + + return 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); + +#ifdef CONFIG_WIRELESS +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); +#endif + +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 noinline void call_trace_sock_recv_length(struct sock *sk, int ret, int flags) +{ + trace_sock_recv_length(sk, ret, flags); +} + +static inline int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg, + int flags) +{ + int ret = INDIRECT_CALL_INET(READ_ONCE(sock->ops)->recvmsg, + inet6_recvmsg, + inet_recvmsg, sock, msg, + msg_data_left(msg), flags); + if (trace_sock_recv_length_enabled()) + call_trace_sock_recv_length(sock->sk, ret, flags); + return ret; +} + +/** + * 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_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; + const struct proto_ops *ops; + + ops = READ_ONCE(sock->ops); + if (unlikely(!ops->splice_read)) + return copy_splice_read(file, ppos, pipe, len, flags); + + return ops->splice_read(sock, ppos, pipe, len, flags); +} + +static void sock_splice_eof(struct file *file) +{ + struct socket *sock = file->private_data; + const struct proto_ops *ops; + + ops = READ_ONCE(sock->ops); + if (ops->splice_eof) + 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) +{ + const struct proto_ops *ops = READ_ONCE(sock->ops); + struct ifreq ifr; + bool need_copyout; + int err; + void __user *argp = (void __user *)arg; + void __user *data; + + err = 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) +{ + const struct proto_ops *ops; + struct socket *sock; + struct sock *sk; + void __user *argp = (void __user *)arg; + int pid, err; + struct net *net; + + sock = file->private_data; + ops = READ_ONCE(sock->ops); + 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 (!ops->gettstamp) { + err = -ENOIOCTLCMD; + break; + } + err = ops->gettstamp(sock, argp, + cmd == SIOCGSTAMP_OLD, + !IS_ENABLED(CONFIG_64BIT)); + break; + case SIOCGSTAMP_NEW: + case SIOCGSTAMPNS_NEW: + if (!ops->gettstamp) { + err = -ENOIOCTLCMD; + break; + } + err = 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; + const struct proto_ops *ops = READ_ONCE(sock->ops); + __poll_t events = poll_requested_events(wait), flag = 0; + + if (!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 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 READ_ONCE(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); +} + +/* A hook for bpf progs to attach to and update socket protocol. + * + * A static noinline declaration here could cause the compiler to + * optimize away the function. A global noinline declaration will + * keep the definition, but may optimize away the callsite. + * Therefore, __weak is needed to ensure that the call is still + * emitted, by telling the compiler that we don't know what the + * function might eventually be. + * + * __diag_* below are needed to dismiss the missing prototype warning. + */ + +__diag_push(); +__diag_ignore_all("-Wmissing-prototypes", + "A fmod_ret entry point for BPF programs"); + +__weak noinline int update_socket_protocol(int family, int type, int protocol) +{ + return protocol; +} + +__diag_pop(); + +int __sys_socket(int family, int type, int protocol) +{ + struct socket *sock; + int flags; + + sock = __sys_socket_create(family, type, + update_socket_protocol(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 = READ_ONCE(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 = READ_ONCE(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 = READ_ONCE(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; + const struct proto_ops *ops; + + sock = sock_from_file(file); + if (!sock) + return ERR_PTR(-ENOTSOCK); + + newsock = sock_alloc(); + if (!newsock) + return ERR_PTR(-ENFILE); + ops = READ_ONCE(sock->ops); + + newsock->type = sock->type; + newsock->ops = ops; + + /* + * We don't need try_module_get here, as the listening socket (sock) + * has the protocol module (sock->ops->owner) held. + */ + __module_get(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 = ops->accept(sock, newsock, sock->file->f_flags | file_flags, + false); + if (err < 0) + goto out_fd; + + if (upeer_sockaddr) { + len = 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 = READ_ONCE(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 = READ_ONCE(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) { + const struct proto_ops *ops = READ_ONCE(sock->ops); + + err = security_socket_getpeername(sock); + if (err) { + fput_light(sock->file, fput_needed); + return err; + } + + err = 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) +{ + return test_bit(SOCK_CUSTOM_SOCKOPT, &sock->flags); +} + +/* + * 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); + const struct proto_ops *ops; + 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); + ops = READ_ONCE(sock->ops); + if (level == SOL_SOCKET && !sock_use_custom_sol_socket(sock)) + err = sock_setsockopt(sock, level, optname, optval, optlen); + else if (unlikely(!ops->setsockopt)) + err = -EOPNOTSUPP; + else + err = 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 max_optlen __maybe_unused; + const struct proto_ops *ops; + int err, fput_needed; + struct socket *sock; + + 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); + + ops = READ_ONCE(sock->ops); + if (level == SOL_SOCKET) + err = sock_getsockopt(sock, level, optname, optval, optlen); + else if (unlikely(!ops->getsockopt)) + err = -EOPNOTSUPP; + else + err = 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 = READ_ONCE(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); + const struct proto_ops *ops; + + 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: + ops = READ_ONCE(sock->ops); + if (!ops->gettstamp) + return -ENOIOCTLCMD; + return 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; + const struct proto_ops *ops = READ_ONCE(sock->ops); + int ret = -ENOIOCTLCMD; + struct sock *sk; + struct net *net; + + sk = sock->sk; + net = sock_net(sk); + + if (ops->compat_ioctl) + ret = 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 READ_ONCE(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 READ_ONCE(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; + const struct proto_ops *ops = READ_ONCE(sock->ops); + int err; + + err = sock_create_lite(sk->sk_family, sk->sk_type, sk->sk_protocol, + newsock); + if (err < 0) + goto done; + + err = ops->accept(sock, *newsock, flags, true); + if (err < 0) { + sock_release(*newsock); + *newsock = NULL; + goto done; + } + + (*newsock)->ops = ops; + __module_get(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 READ_ONCE(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 READ_ONCE(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 READ_ONCE(sock->ops)->getname(sock, addr, 1); +} +EXPORT_SYMBOL(kernel_getpeername); + +/** + * 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 READ_ONCE(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); |