1 files changed, 103 insertions, 169 deletions

diff --git a/fs/fcntl.c b/fs/fcntl.c
index ecc8b3954ed..72c82f69b01 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -20,134 +20,17 @@
 #include <linux/signal.h>
 #include <linux/rcupdate.h>
 #include <linux/pid_namespace.h>
+#include <linux/user_namespace.h>
 
 #include <asm/poll.h>
 #include <asm/siginfo.h>
 #include <asm/uaccess.h>
 
-void set_close_on_exec(unsigned int fd, int flag)
-{
-	struct files_struct *files = current->files;
-	struct fdtable *fdt;
-	spin_lock(&files->file_lock);
-	fdt = files_fdtable(files);
-	if (flag)
-		FD_SET(fd, fdt->close_on_exec);
-	else
-		FD_CLR(fd, fdt->close_on_exec);
-	spin_unlock(&files->file_lock);
-}
-
-static int get_close_on_exec(unsigned int fd)
-{
-	struct files_struct *files = current->files;
-	struct fdtable *fdt;
-	int res;
-	rcu_read_lock();
-	fdt = files_fdtable(files);
-	res = FD_ISSET(fd, fdt->close_on_exec);
-	rcu_read_unlock();
-	return res;
-}
-
-SYSCALL_DEFINE3(dup3, unsigned int, oldfd, unsigned int, newfd, int, flags)
-{
-	int err = -EBADF;
-	struct file * file, *tofree;
-	struct files_struct * files = current->files;
-	struct fdtable *fdt;
-
-	if ((flags & ~O_CLOEXEC) != 0)
-		return -EINVAL;
-
-	if (unlikely(oldfd == newfd))
-		return -EINVAL;
-
-	spin_lock(&files->file_lock);
-	err = expand_files(files, newfd);
-	file = fcheck(oldfd);
-	if (unlikely(!file))
-		goto Ebadf;
-	if (unlikely(err < 0)) {
-		if (err == -EMFILE)
-			goto Ebadf;
-		goto out_unlock;
-	}
-	/*
-	 * We need to detect attempts to do dup2() over allocated but still
-	 * not finished descriptor.  NB: OpenBSD avoids that at the price of
-	 * extra work in their equivalent of fget() - they insert struct
-	 * file immediately after grabbing descriptor, mark it larval if
-	 * more work (e.g. actual opening) is needed and make sure that
-	 * fget() treats larval files as absent.  Potentially interesting,
-	 * but while extra work in fget() is trivial, locking implications
-	 * and amount of surgery on open()-related paths in VFS are not.
-	 * FreeBSD fails with -EBADF in the same situation, NetBSD "solution"
-	 * deadlocks in rather amusing ways, AFAICS.  All of that is out of
-	 * scope of POSIX or SUS, since neither considers shared descriptor
-	 * tables and this condition does not arise without those.
-	 */
-	err = -EBUSY;
-	fdt = files_fdtable(files);
-	tofree = fdt->fd[newfd];
-	if (!tofree && FD_ISSET(newfd, fdt->open_fds))
-		goto out_unlock;
-	get_file(file);
-	rcu_assign_pointer(fdt->fd[newfd], file);
-	FD_SET(newfd, fdt->open_fds);
-	if (flags & O_CLOEXEC)
-		FD_SET(newfd, fdt->close_on_exec);
-	else
-		FD_CLR(newfd, fdt->close_on_exec);
-	spin_unlock(&files->file_lock);
-
-	if (tofree)
-		filp_close(tofree, files);
-
-	return newfd;
-
-Ebadf:
-	err = -EBADF;
-out_unlock:
-	spin_unlock(&files->file_lock);
-	return err;
-}
-
-SYSCALL_DEFINE2(dup2, unsigned int, oldfd, unsigned int, newfd)
-{
-	if (unlikely(newfd == oldfd)) { /* corner case */
-		struct files_struct *files = current->files;
-		int retval = oldfd;
-
-		rcu_read_lock();
-		if (!fcheck_files(files, oldfd))
-			retval = -EBADF;
-		rcu_read_unlock();
-		return retval;
-	}
-	return sys_dup3(oldfd, newfd, 0);
-}
-
-SYSCALL_DEFINE1(dup, unsigned int, fildes)
-{
-	int ret = -EBADF;
-	struct file *file = fget(fildes);
-
-	if (file) {
-		ret = get_unused_fd();
-		if (ret >= 0)
-			fd_install(ret, file);
-		else
-			fput(file);
-	}
-	return ret;
-}
-
 #define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | O_DIRECT | O_NOATIME)
 
 static int setfl(int fd, struct file * filp, unsigned long arg)
 {
-	struct inode * inode = filp->f_path.dentry->d_inode;
+	struct inode * inode = file_inode(filp);
 	int error = 0;
 
 	/*
@@ -159,7 +42,7 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
 
 	/* O_NOATIME can only be set by the owner or superuser */
 	if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME))
-		if (!is_owner_or_cap(inode))
+		if (!inode_owner_or_capable(inode))
 			return -EPERM;
 
 	/* required for strict SunOS emulation */
@@ -173,7 +56,7 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
 				return -EINVAL;
 	}
 
-	if (filp->f_op && filp->f_op->check_flags)
+	if (filp->f_op->check_flags)
 		error = filp->f_op->check_flags(arg);
 	if (error)
 		return error;
@@ -181,8 +64,7 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
 	/*
 	 * ->fasync() is responsible for setting the FASYNC bit.
 	 */
-	if (((arg ^ filp->f_flags) & FASYNC) && filp->f_op &&
-			filp->f_op->fasync) {
+	if (((arg ^ filp->f_flags) & FASYNC) && filp->f_op->fasync) {
 		error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0);
 		if (error < 0)
 			goto out;
@@ -266,7 +148,7 @@ pid_t f_getown(struct file *filp)
 
 static int f_setown_ex(struct file *filp, unsigned long arg)
 {
-	struct f_owner_ex * __user owner_p = (void * __user)arg;
+	struct f_owner_ex __user *owner_p = (void __user *)arg;
 	struct f_owner_ex owner;
 	struct pid *pid;
 	int type;
@@ -306,7 +188,7 @@ static int f_setown_ex(struct file *filp, unsigned long arg)
 
 static int f_getown_ex(struct file *filp, unsigned long arg)
 {
-	struct f_owner_ex * __user owner_p = (void * __user)arg;
+	struct f_owner_ex __user *owner_p = (void __user *)arg;
 	struct f_owner_ex owner;
 	int ret = 0;
 
@@ -340,6 +222,31 @@ static int f_getown_ex(struct file *filp, unsigned long arg)
 	return ret;
 }
 
+#ifdef CONFIG_CHECKPOINT_RESTORE
+static int f_getowner_uids(struct file *filp, unsigned long arg)
+{
+	struct user_namespace *user_ns = current_user_ns();
+	uid_t __user *dst = (void __user *)arg;
+	uid_t src[2];
+	int err;
+
+	read_lock(&filp->f_owner.lock);
+	src[0] = from_kuid(user_ns, filp->f_owner.uid);
+	src[1] = from_kuid(user_ns, filp->f_owner.euid);
+	read_unlock(&filp->f_owner.lock);
+
+	err  = put_user(src[0], &dst[0]);
+	err |= put_user(src[1], &dst[1]);
+
+	return err;
+}
+#else
+static int f_getowner_uids(struct file *filp, unsigned long arg)
+{
+	return -EINVAL;
+}
+#endif
+
 static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
 		struct file *filp)
 {
@@ -347,14 +254,10 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
 
 	switch (cmd) {
 	case F_DUPFD:
+		err = f_dupfd(arg, filp, 0);
+		break;
 	case F_DUPFD_CLOEXEC:
-		if (arg >= rlimit(RLIMIT_NOFILE))
-			break;
-		err = alloc_fd(arg, cmd == F_DUPFD_CLOEXEC ? O_CLOEXEC : 0);
-		if (err >= 0) {
-			get_file(filp);
-			fd_install(err, filp);
-		}
+		err = f_dupfd(arg, filp, O_CLOEXEC);
 		break;
 	case F_GETFD:
 		err = get_close_on_exec(fd) ? FD_CLOEXEC : 0;
@@ -369,9 +272,19 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
 	case F_SETFL:
 		err = setfl(fd, filp, arg);
 		break;
+#if BITS_PER_LONG != 32
+	/* 32-bit arches must use fcntl64() */
+	case F_OFD_GETLK:
+#endif
 	case F_GETLK:
-		err = fcntl_getlk(filp, (struct flock __user *) arg);
+		err = fcntl_getlk(filp, cmd, (struct flock __user *) arg);
 		break;
+#if BITS_PER_LONG != 32
+	/* 32-bit arches must use fcntl64() */
+	case F_OFD_SETLK:
+	case F_OFD_SETLKW:
+#endif
+		/* Fallthrough */
 	case F_SETLK:
 	case F_SETLKW:
 		err = fcntl_setlk(fd, filp, cmd, (struct flock __user *) arg);
@@ -396,6 +309,9 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
 	case F_SETOWN_EX:
 		err = f_setown_ex(filp, arg);
 		break;
+	case F_GETOWNER_UIDS:
+		err = f_getowner_uids(filp, arg);
+		break;
 	case F_GETSIG:
 		err = filp->f_owner.signum;
 		break;
@@ -426,24 +342,38 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
 	return err;
 }
 
+static int check_fcntl_cmd(unsigned cmd)
+{
+	switch (cmd) {
+	case F_DUPFD:
+	case F_DUPFD_CLOEXEC:
+	case F_GETFD:
+	case F_SETFD:
+	case F_GETFL:
+		return 1;
+	}
+	return 0;
+}
+
 SYSCALL_DEFINE3(fcntl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
 {	
-	struct file *filp;
+	struct fd f = fdget_raw(fd);
 	long err = -EBADF;
 
-	filp = fget(fd);
-	if (!filp)
+	if (!f.file)
 		goto out;
 
-	err = security_file_fcntl(filp, cmd, arg);
-	if (err) {
-		fput(filp);
-		return err;
+	if (unlikely(f.file->f_mode & FMODE_PATH)) {
+		if (!check_fcntl_cmd(cmd))
+			goto out1;
 	}
 
-	err = do_fcntl(fd, cmd, arg, filp);
+	err = security_file_fcntl(f.file, cmd, arg);
+	if (!err)
+		err = do_fcntl(fd, cmd, arg, f.file);
 
- 	fput(filp);
+out1:
+ 	fdput(f);
 out:
 	return err;
 }
@@ -452,35 +382,39 @@ out:
 SYSCALL_DEFINE3(fcntl64, unsigned int, fd, unsigned int, cmd,
 		unsigned long, arg)
 {	
-	struct file * filp;
-	long err;
+	struct fd f = fdget_raw(fd);
+	long err = -EBADF;
 
-	err = -EBADF;
-	filp = fget(fd);
-	if (!filp)
+	if (!f.file)
 		goto out;
 
-	err = security_file_fcntl(filp, cmd, arg);
-	if (err) {
-		fput(filp);
-		return err;
+	if (unlikely(f.file->f_mode & FMODE_PATH)) {
+		if (!check_fcntl_cmd(cmd))
+			goto out1;
 	}
-	err = -EBADF;
+
+	err = security_file_fcntl(f.file, cmd, arg);
+	if (err)
+		goto out1;
 	
 	switch (cmd) {
-		case F_GETLK64:
-			err = fcntl_getlk64(filp, (struct flock64 __user *) arg);
-			break;
-		case F_SETLK64:
-		case F_SETLKW64:
-			err = fcntl_setlk64(fd, filp, cmd,
-					(struct flock64 __user *) arg);
-			break;
-		default:
-			err = do_fcntl(fd, cmd, arg, filp);
-			break;
+	case F_GETLK64:
+	case F_OFD_GETLK:
+		err = fcntl_getlk64(f.file, cmd, (struct flock64 __user *) arg);
+		break;
+	case F_SETLK64:
+	case F_SETLKW64:
+	case F_OFD_SETLK:
+	case F_OFD_SETLKW:
+		err = fcntl_setlk64(fd, f.file, cmd,
+				(struct flock64 __user *) arg);
+		break;
+	default:
+		err = do_fcntl(fd, cmd, arg, f.file);
+		break;
 	}
-	fput(filp);
+out1:
+	fdput(f);
 out:
 	return err;
 }
@@ -505,9 +439,9 @@ static inline int sigio_perm(struct task_struct *p,
 
 	rcu_read_lock();
 	cred = __task_cred(p);
-	ret = ((fown->euid == 0 ||
-		fown->euid == cred->suid || fown->euid == cred->uid ||
-		fown->uid  == cred->suid || fown->uid  == cred->uid) &&
+	ret = ((uid_eq(fown->euid, GLOBAL_ROOT_UID) ||
+		uid_eq(fown->euid, cred->suid) || uid_eq(fown->euid, cred->uid) ||
+		uid_eq(fown->uid,  cred->suid) || uid_eq(fown->uid,  cred->uid)) &&
 	       !security_file_send_sigiotask(p, fown, sig));
 	rcu_read_unlock();
 	return ret;
@@ -808,14 +742,14 @@ static int __init fcntl_init(void)
 	 * Exceptions: O_NONBLOCK is a two bit define on parisc; O_NDELAY
 	 * is defined as O_NONBLOCK on some platforms and not on others.
 	 */
-	BUILD_BUG_ON(18 - 1 /* for O_RDONLY being 0 */ != HWEIGHT32(
+	BUILD_BUG_ON(20 - 1 /* for O_RDONLY being 0 */ != HWEIGHT32(
 		O_RDONLY	| O_WRONLY	| O_RDWR	|
 		O_CREAT		| O_EXCL	| O_NOCTTY	|
 		O_TRUNC		| O_APPEND	| /* O_NONBLOCK	| */
 		__O_SYNC	| O_DSYNC	| FASYNC	|
 		O_DIRECT	| O_LARGEFILE	| O_DIRECTORY	|
 		O_NOFOLLOW	| O_NOATIME	| O_CLOEXEC	|
-		FMODE_EXEC
+		__FMODE_EXEC	| O_PATH	| __O_TMPFILE
 		));
 
 	fasync_cache = kmem_cache_create("fasync_cache",