1 files changed, 191 insertions, 141 deletions

diff --git a/net/socket.c b/net/socket.c
index 7e1bdef8b09e..e3c21d5ec288 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -68,6 +68,7 @@
 #include <linux/netdevice.h>
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
+#include <linux/mutex.h>
 #include <linux/wanrouter.h>
 #include <linux/if_bridge.h>
 #include <linux/if_frad.h>
@@ -348,8 +349,8 @@ static struct dentry_operations sockfs_dentry_operations = {
 /*
  *	Obtains the first available file descriptor and sets it up for use.
  *
- *	This function creates file structure and maps it to fd space
- *	of current process. On success it returns file descriptor
+ *	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
@@ -362,53 +363,90 @@ static struct dentry_operations sockfs_dentry_operations = {
  *	but we take care of internal coherence yet.
  */
 
-int sock_map_fd(struct socket *sock)
+static int sock_alloc_fd(struct file **filep)
 {
 	int fd;
-	struct qstr this;
-	char name[32];
-
-	/*
-	 *	Find a file descriptor suitable for return to the user. 
-	 */
 
 	fd = get_unused_fd();
-	if (fd >= 0) {
+	if (likely(fd >= 0)) {
 		struct file *file = get_empty_filp();
 
-		if (!file) {
+		*filep = file;
+		if (unlikely(!file)) {
 			put_unused_fd(fd);
-			fd = -ENFILE;
-			goto out;
+			return -ENFILE;
 		}
+	} else
+		*filep = NULL;
+	return fd;
+}
+
+static int sock_attach_fd(struct socket *sock, struct file *file)
+{
+	struct qstr this;
+	char name[32];
+
+	this.len = sprintf(name, "[%lu]", SOCK_INODE(sock)->i_ino);
+	this.name = name;
+	this.hash = SOCK_INODE(sock)->i_ino;
 
-		this.len = sprintf(name, "[%lu]", SOCK_INODE(sock)->i_ino);
-		this.name = name;
-		this.hash = SOCK_INODE(sock)->i_ino;
+	file->f_dentry = d_alloc(sock_mnt->mnt_sb->s_root, &this);
+	if (unlikely(!file->f_dentry))
+		return -ENOMEM;
+
+	file->f_dentry->d_op = &sockfs_dentry_operations;
+	d_add(file->f_dentry, SOCK_INODE(sock));
+	file->f_vfsmnt = mntget(sock_mnt);
+	file->f_mapping = file->f_dentry->d_inode->i_mapping;
+
+	sock->file = file;
+	file->f_op = SOCK_INODE(sock)->i_fop = &socket_file_ops;
+	file->f_mode = FMODE_READ | FMODE_WRITE;
+	file->f_flags = O_RDWR;
+	file->f_pos = 0;
+	file->private_data = sock;
+
+	return 0;
+}
 
-		file->f_dentry = d_alloc(sock_mnt->mnt_sb->s_root, &this);
-		if (!file->f_dentry) {
-			put_filp(file);
+int sock_map_fd(struct socket *sock)
+{
+	struct file *newfile;
+	int fd = sock_alloc_fd(&newfile);
+
+	if (likely(fd >= 0)) {
+		int err = sock_attach_fd(sock, newfile);
+
+		if (unlikely(err < 0)) {
+			put_filp(newfile);
 			put_unused_fd(fd);
-			fd = -ENOMEM;
-			goto out;
+			return err;
 		}
-		file->f_dentry->d_op = &sockfs_dentry_operations;
-		d_add(file->f_dentry, SOCK_INODE(sock));
-		file->f_vfsmnt = mntget(sock_mnt);
-		file->f_mapping = file->f_dentry->d_inode->i_mapping;
+		fd_install(fd, newfile);
+	}
+	return fd;
+}
 
-		sock->file = file;
-		file->f_op = SOCK_INODE(sock)->i_fop = &socket_file_ops;
-		file->f_mode = FMODE_READ | FMODE_WRITE;
-		file->f_flags = O_RDWR;
-		file->f_pos = 0;
-		file->private_data = sock;
-		fd_install(fd, file);
+static struct socket *sock_from_file(struct file *file, int *err)
+{
+	struct inode *inode;
+	struct socket *sock;
+
+	if (file->f_op == &socket_file_ops)
+		return file->private_data;	/* set in sock_map_fd */
+
+	inode = file->f_dentry->d_inode;
+	if (!S_ISSOCK(inode->i_mode)) {
+		*err = -ENOTSOCK;
+		return NULL;
 	}
 
-out:
-	return fd;
+	sock = SOCKET_I(inode);
+	if (sock->file != file) {
+		printk(KERN_ERR "socki_lookup: socket file changed!\n");
+		sock->file = file;
+	}
+	return sock;
 }
 
 /**
@@ -427,31 +465,31 @@ out:
 struct socket *sockfd_lookup(int fd, int *err)
 {
 	struct file *file;
-	struct inode *inode;
 	struct socket *sock;
 
-	if (!(file = fget(fd)))
-	{
+	if (!(file = fget(fd))) {
 		*err = -EBADF;
 		return NULL;
 	}
-
-	if (file->f_op == &socket_file_ops)
-		return file->private_data;	/* set in sock_map_fd */
-
-	inode = file->f_dentry->d_inode;
-	if (!S_ISSOCK(inode->i_mode)) {
-		*err = -ENOTSOCK;
+	sock = sock_from_file(file, err);
+	if (!sock)
 		fput(file);
-		return NULL;
-	}
+	return sock;
+}
 
-	sock = SOCKET_I(inode);
-	if (sock->file != file) {
-		printk(KERN_ERR "socki_lookup: socket file changed!\n");
-		sock->file = file;
+static struct socket *sockfd_lookup_light(int fd, int *err, int *fput_needed)
+{
+	struct file *file;
+	struct socket *sock;
+
+	file = fget_light(fd, fput_needed);
+	if (file) {
+		sock = sock_from_file(file, err);
+		if (sock)
+			return sock;
+		fput_light(file, *fput_needed);
 	}
-	return sock;
+	return NULL;
 }
 
 /**
@@ -789,36 +827,36 @@ static ssize_t sock_aio_write(struct kiocb *iocb, const char __user *ubuf,
  * with module unload.
  */
 
-static DECLARE_MUTEX(br_ioctl_mutex);
+static DEFINE_MUTEX(br_ioctl_mutex);
 static int (*br_ioctl_hook)(unsigned int cmd, void __user *arg) = NULL;
 
 void brioctl_set(int (*hook)(unsigned int, void __user *))
 {
-	down(&br_ioctl_mutex);
+	mutex_lock(&br_ioctl_mutex);
 	br_ioctl_hook = hook;
-	up(&br_ioctl_mutex);
+	mutex_unlock(&br_ioctl_mutex);
 }
 EXPORT_SYMBOL(brioctl_set);
 
-static DECLARE_MUTEX(vlan_ioctl_mutex);
+static DEFINE_MUTEX(vlan_ioctl_mutex);
 static int (*vlan_ioctl_hook)(void __user *arg);
 
 void vlan_ioctl_set(int (*hook)(void __user *))
 {
-	down(&vlan_ioctl_mutex);
+	mutex_lock(&vlan_ioctl_mutex);
 	vlan_ioctl_hook = hook;
-	up(&vlan_ioctl_mutex);
+	mutex_unlock(&vlan_ioctl_mutex);
 }
 EXPORT_SYMBOL(vlan_ioctl_set);
 
-static DECLARE_MUTEX(dlci_ioctl_mutex);
+static DEFINE_MUTEX(dlci_ioctl_mutex);
 static int (*dlci_ioctl_hook)(unsigned int, void __user *);
 
 void dlci_ioctl_set(int (*hook)(unsigned int, void __user *))
 {
-	down(&dlci_ioctl_mutex);
+	mutex_lock(&dlci_ioctl_mutex);
 	dlci_ioctl_hook = hook;
-	up(&dlci_ioctl_mutex);
+	mutex_unlock(&dlci_ioctl_mutex);
 }
 EXPORT_SYMBOL(dlci_ioctl_set);
 
@@ -862,10 +900,10 @@ static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 			if (!br_ioctl_hook)
 				request_module("bridge");
 
-			down(&br_ioctl_mutex);
+			mutex_lock(&br_ioctl_mutex);
 			if (br_ioctl_hook) 
 				err = br_ioctl_hook(cmd, argp);
-			up(&br_ioctl_mutex);
+			mutex_unlock(&br_ioctl_mutex);
 			break;
 		case SIOCGIFVLAN:
 		case SIOCSIFVLAN:
@@ -873,10 +911,10 @@ static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 			if (!vlan_ioctl_hook)
 				request_module("8021q");
 
-			down(&vlan_ioctl_mutex);
+			mutex_lock(&vlan_ioctl_mutex);
 			if (vlan_ioctl_hook)
 				err = vlan_ioctl_hook(argp);
-			up(&vlan_ioctl_mutex);
+			mutex_unlock(&vlan_ioctl_mutex);
 			break;
 		case SIOCGIFDIVERT:
 		case SIOCSIFDIVERT:
@@ -890,9 +928,9 @@ static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 				request_module("dlci");
 
 			if (dlci_ioctl_hook) {
-				down(&dlci_ioctl_mutex);
+				mutex_lock(&dlci_ioctl_mutex);
 				err = dlci_ioctl_hook(cmd, argp);
-				up(&dlci_ioctl_mutex);
+				mutex_unlock(&dlci_ioctl_mutex);
 			}
 			break;
 		default:
@@ -1286,19 +1324,17 @@ asmlinkage long sys_bind(int fd, struct sockaddr __user *umyaddr, int addrlen)
 {
 	struct socket *sock;
 	char address[MAX_SOCK_ADDR];
-	int err;
+	int err, fput_needed;
 
-	if((sock = sockfd_lookup(fd,&err))!=NULL)
+	if((sock = sockfd_lookup_light(fd, &err, &fput_needed))!=NULL)
 	{
 		if((err=move_addr_to_kernel(umyaddr,addrlen,address))>=0) {
 			err = security_socket_bind(sock, (struct sockaddr *)address, addrlen);
-			if (err) {
-				sockfd_put(sock);
-				return err;
-			}
-			err = sock->ops->bind(sock, (struct sockaddr *)address, addrlen);
+			if (!err)
+				err = sock->ops->bind(sock,
+					(struct sockaddr *)address, addrlen);
 		}
-		sockfd_put(sock);
+		fput_light(sock->file, fput_needed);
 	}			
 	return err;
 }
@@ -1315,20 +1351,17 @@ int sysctl_somaxconn = SOMAXCONN;
 asmlinkage long sys_listen(int fd, int backlog)
 {
 	struct socket *sock;
-	int err;
+	int err, fput_needed;
 	
-	if ((sock = sockfd_lookup(fd, &err)) != NULL) {
+	if ((sock = sockfd_lookup_light(fd, &err, &fput_needed)) != NULL) {
 		if ((unsigned) backlog > sysctl_somaxconn)
 			backlog = sysctl_somaxconn;
 
 		err = security_socket_listen(sock, backlog);
-		if (err) {
-			sockfd_put(sock);
-			return err;
-		}
+		if (!err)
+			err = sock->ops->listen(sock, backlog);
 
-		err=sock->ops->listen(sock, backlog);
-		sockfd_put(sock);
+		fput_light(sock->file, fput_needed);
 	}
 	return err;
 }
@@ -1349,10 +1382,11 @@ asmlinkage long sys_listen(int fd, int backlog)
 asmlinkage long sys_accept(int fd, struct sockaddr __user *upeer_sockaddr, int __user *upeer_addrlen)
 {
 	struct socket *sock, *newsock;
-	int err, len;
+	struct file *newfile;
+	int err, len, newfd, fput_needed;
 	char address[MAX_SOCK_ADDR];
 
-	sock = sockfd_lookup(fd, &err);
+	sock = sockfd_lookup_light(fd, &err, &fput_needed);
 	if (!sock)
 		goto out;
 
@@ -1369,35 +1403,48 @@ asmlinkage long sys_accept(int fd, struct sockaddr __user *upeer_sockaddr, int _
 	 */
 	__module_get(newsock->ops->owner);
 
+	newfd = sock_alloc_fd(&newfile);
+	if (unlikely(newfd < 0)) {
+		err = newfd;
+		goto out_release;
+	}
+
+	err = sock_attach_fd(newsock, newfile);
+	if (err < 0)
+		goto out_fd;
+
 	err = security_socket_accept(sock, newsock);
 	if (err)
-		goto out_release;
+		goto out_fd;
 
 	err = sock->ops->accept(sock, newsock, sock->file->f_flags);
 	if (err < 0)
-		goto out_release;
+		goto out_fd;
 
 	if (upeer_sockaddr) {
 		if(newsock->ops->getname(newsock, (struct sockaddr *)address, &len, 2)<0) {
 			err = -ECONNABORTED;
-			goto out_release;
+			goto out_fd;
 		}
 		err = move_addr_to_user(address, len, upeer_sockaddr, upeer_addrlen);
 		if (err < 0)
-			goto out_release;
+			goto out_fd;
 	}
 
 	/* File flags are not inherited via accept() unlike another OSes. */
 
-	if ((err = sock_map_fd(newsock)) < 0)
-		goto out_release;
+	fd_install(newfd, newfile);
+	err = newfd;
 
 	security_socket_post_accept(sock, newsock);
 
 out_put:
-	sockfd_put(sock);
+	fput_light(sock->file, fput_needed);
 out:
 	return err;
+out_fd:
+	put_filp(newfile);
+	put_unused_fd(newfd);
 out_release:
 	sock_release(newsock);
 	goto out_put;
@@ -1420,9 +1467,9 @@ asmlinkage long sys_connect(int fd, struct sockaddr __user *uservaddr, int addrl
 {
 	struct socket *sock;
 	char address[MAX_SOCK_ADDR];
-	int err;
+	int err, fput_needed;
 
-	sock = sockfd_lookup(fd, &err);
+	sock = sockfd_lookup_light(fd, &err, &fput_needed);
 	if (!sock)
 		goto out;
 	err = move_addr_to_kernel(uservaddr, addrlen, address);
@@ -1436,7 +1483,7 @@ asmlinkage long sys_connect(int fd, struct sockaddr __user *uservaddr, int addrl
 	err = sock->ops->connect(sock, (struct sockaddr *) address, addrlen,
 				 sock->file->f_flags);
 out_put:
-	sockfd_put(sock);
+	fput_light(sock->file, fput_needed);
 out:
 	return err;
 }
@@ -1450,9 +1497,9 @@ asmlinkage long sys_getsockname(int fd, struct sockaddr __user *usockaddr, int _
 {
 	struct socket *sock;
 	char address[MAX_SOCK_ADDR];
-	int len, err;
+	int len, err, fput_needed;
 	
-	sock = sockfd_lookup(fd, &err);
+	sock = sockfd_lookup_light(fd, &err, &fput_needed);
 	if (!sock)
 		goto out;
 
@@ -1466,7 +1513,7 @@ asmlinkage long sys_getsockname(int fd, struct sockaddr __user *usockaddr, int _
 	err = move_addr_to_user(address, len, usockaddr, usockaddr_len);
 
 out_put:
-	sockfd_put(sock);
+	fput_light(sock->file, fput_needed);
 out:
 	return err;
 }
@@ -1480,20 +1527,19 @@ asmlinkage long sys_getpeername(int fd, struct sockaddr __user *usockaddr, int _
 {
 	struct socket *sock;
 	char address[MAX_SOCK_ADDR];
-	int len, err;
+	int len, err, fput_needed;
 
-	if ((sock = sockfd_lookup(fd, &err))!=NULL)
-	{
+	if ((sock = sockfd_lookup_light(fd, &err, &fput_needed)) != NULL) {
 		err = security_socket_getpeername(sock);
 		if (err) {
-			sockfd_put(sock);
+			fput_light(sock->file, fput_needed);
 			return err;
 		}
 
 		err = sock->ops->getname(sock, (struct sockaddr *)address, &len, 1);
 		if (!err)
 			err=move_addr_to_user(address,len, usockaddr, usockaddr_len);
-		sockfd_put(sock);
+		fput_light(sock->file, fput_needed);
 	}
 	return err;
 }
@@ -1512,10 +1558,16 @@ asmlinkage long sys_sendto(int fd, void __user * buff, size_t len, unsigned flag
 	int err;
 	struct msghdr msg;
 	struct iovec iov;
-	
-	sock = sockfd_lookup(fd, &err);
+	int fput_needed;
+	struct file *sock_file;
+
+	sock_file = fget_light(fd, &fput_needed);
+	if (!sock_file)
+		return -EBADF;
+
+	sock = sock_from_file(sock_file, &err);
 	if (!sock)
-		goto out;
+		goto out_put;
 	iov.iov_base=buff;
 	iov.iov_len=len;
 	msg.msg_name=NULL;
@@ -1524,8 +1576,7 @@ asmlinkage long sys_sendto(int fd, void __user * buff, size_t len, unsigned flag
 	msg.msg_control=NULL;
 	msg.msg_controllen=0;
 	msg.msg_namelen=0;
-	if(addr)
-	{
+	if (addr) {
 		err = move_addr_to_kernel(addr, addr_len, address);
 		if (err < 0)
 			goto out_put;
@@ -1538,8 +1589,7 @@ asmlinkage long sys_sendto(int fd, void __user * buff, size_t len, unsigned flag
 	err = sock_sendmsg(sock, &msg, len);
 
 out_put:		
-	sockfd_put(sock);
-out:
+	fput_light(sock_file, fput_needed);
 	return err;
 }
 
@@ -1566,8 +1616,14 @@ asmlinkage long sys_recvfrom(int fd, void __user * ubuf, size_t size, unsigned f
 	struct msghdr msg;
 	char address[MAX_SOCK_ADDR];
 	int err,err2;
+	struct file *sock_file;
+	int fput_needed;
 
-	sock = sockfd_lookup(fd, &err);
+	sock_file = fget_light(fd, &fput_needed);
+	if (!sock_file)
+		return -EBADF;
+
+	sock = sock_from_file(sock_file, &err);
 	if (!sock)
 		goto out;
 
@@ -1589,8 +1645,8 @@ asmlinkage long sys_recvfrom(int fd, void __user * ubuf, size_t size, unsigned f
 		if(err2<0)
 			err=err2;
 	}
-	sockfd_put(sock);			
 out:
+	fput_light(sock_file, fput_needed);
 	return err;
 }
 
@@ -1610,25 +1666,24 @@ asmlinkage long sys_recv(int fd, void __user * ubuf, size_t size, unsigned flags
 
 asmlinkage long sys_setsockopt(int fd, int level, int optname, char __user *optval, int optlen)
 {
-	int err;
+	int err, fput_needed;
 	struct socket *sock;
 
 	if (optlen < 0)
 		return -EINVAL;
 			
-	if ((sock = sockfd_lookup(fd, &err))!=NULL)
+	if ((sock = sockfd_lookup_light(fd, &err, &fput_needed)) != NULL)
 	{
 		err = security_socket_setsockopt(sock,level,optname);
-		if (err) {
-			sockfd_put(sock);
-			return err;
-		}
+		if (err)
+			goto out_put;
 
 		if (level == SOL_SOCKET)
 			err=sock_setsockopt(sock,level,optname,optval,optlen);
 		else
 			err=sock->ops->setsockopt(sock, level, optname, optval, optlen);
-		sockfd_put(sock);
+out_put:
+		fput_light(sock->file, fput_needed);
 	}
 	return err;
 }
@@ -1640,23 +1695,20 @@ asmlinkage long sys_setsockopt(int fd, int level, int optname, char __user *optv
 
 asmlinkage long sys_getsockopt(int fd, int level, int optname, char __user *optval, int __user *optlen)
 {
-	int err;
+	int err, fput_needed;
 	struct socket *sock;
 
-	if ((sock = sockfd_lookup(fd, &err))!=NULL)
-	{
-		err = security_socket_getsockopt(sock, level, 
-							   optname);
-		if (err) {
-			sockfd_put(sock);
-			return err;
-		}
+	if ((sock = sockfd_lookup_light(fd, &err, &fput_needed)) != NULL) {
+		err = security_socket_getsockopt(sock, level, optname);
+		if (err)
+			goto out_put;
 
 		if (level == SOL_SOCKET)
 			err=sock_getsockopt(sock,level,optname,optval,optlen);
 		else
 			err=sock->ops->getsockopt(sock, level, optname, optval, optlen);
-		sockfd_put(sock);
+out_put:
+		fput_light(sock->file, fput_needed);
 	}
 	return err;
 }
@@ -1668,19 +1720,15 @@ asmlinkage long sys_getsockopt(int fd, int level, int optname, char __user *optv
 
 asmlinkage long sys_shutdown(int fd, int how)
 {
-	int err;
+	int err, fput_needed;
 	struct socket *sock;
 
-	if ((sock = sockfd_lookup(fd, &err))!=NULL)
+	if ((sock = sockfd_lookup_light(fd, &err, &fput_needed))!=NULL)
 	{
 		err = security_socket_shutdown(sock, how);
-		if (err) {
-			sockfd_put(sock);
-			return err;
-		}
-				
-		err=sock->ops->shutdown(sock, how);
-		sockfd_put(sock);
+		if (!err)
+			err = sock->ops->shutdown(sock, how);
+		fput_light(sock->file, fput_needed);
 	}
 	return err;
 }
@@ -1709,6 +1757,7 @@ asmlinkage long sys_sendmsg(int fd, struct msghdr __user *msg, unsigned flags)
 	unsigned char *ctl_buf = ctl;
 	struct msghdr msg_sys;
 	int err, ctl_len, iov_size, total_len;
+	int fput_needed;
 	
 	err = -EFAULT;
 	if (MSG_CMSG_COMPAT & flags) {
@@ -1717,7 +1766,7 @@ asmlinkage long sys_sendmsg(int fd, struct msghdr __user *msg, unsigned flags)
 	} else if (copy_from_user(&msg_sys, msg, sizeof(struct msghdr)))
 		return -EFAULT;
 
-	sock = sockfd_lookup(fd, &err);
+	sock = sockfd_lookup_light(fd, &err, &fput_needed);
 	if (!sock) 
 		goto out;
 
@@ -1785,7 +1834,7 @@ out_freeiov:
 	if (iov != iovstack)
 		sock_kfree_s(sock->sk, iov, iov_size);
 out_put:
-	sockfd_put(sock);
+	fput_light(sock->file, fput_needed);
 out:       
 	return err;
 }
@@ -1803,6 +1852,7 @@ asmlinkage long sys_recvmsg(int fd, struct msghdr __user *msg, unsigned int flag
 	struct msghdr msg_sys;
 	unsigned long cmsg_ptr;
 	int err, iov_size, total_len, len;
+	int fput_needed;
 
 	/* kernel mode address */
 	char addr[MAX_SOCK_ADDR];
@@ -1818,7 +1868,7 @@ asmlinkage long sys_recvmsg(int fd, struct msghdr __user *msg, unsigned int flag
 		if (copy_from_user(&msg_sys,msg,sizeof(struct msghdr)))
 			return -EFAULT;
 
-	sock = sockfd_lookup(fd, &err);
+	sock = sockfd_lookup_light(fd, &err, &fput_needed);
 	if (!sock)
 		goto out;
 
@@ -1885,7 +1935,7 @@ out_freeiov:
 	if (iov != iovstack)
 		sock_kfree_s(sock->sk, iov, iov_size);
 out_put:
-	sockfd_put(sock);
+	fput_light(sock->file, fput_needed);
 out:
 	return err;
 }