[mirror_ubuntu-bionic-kernel.git] / fs / ext2 / ioctl.c

/*
 * linux/fs/ext2/ioctl.c
 *
 * Copyright (C) 1993, 1994, 1995
 * Remy Card (card@masi.ibp.fr)
 * Laboratoire MASI - Institut Blaise Pascal
 * Universite Pierre et Marie Curie (Paris VI)
 */

#include "ext2.h"
#include <linux/capability.h>
#include <linux/time.h>
#include <linux/sched.h>
#include <linux/compat.h>
#include <linux/mount.h>
#include <linux/smp_lock.h>
#include <asm/current.h>
#include <asm/uaccess.h>


long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	struct inode *inode = filp->f_dentry->d_inode;
	struct ext2_inode_info *ei = EXT2_I(inode);
	unsigned int flags;
	unsigned short rsv_window_size;
	int ret;

	ext2_debug ("cmd = %u, arg = %lu\n", cmd, arg);

	switch (cmd) {
	case EXT2_IOC_GETFLAGS:
		ext2_get_inode_flags(ei);
		flags = ei->i_flags & EXT2_FL_USER_VISIBLE;
		return put_user(flags, (int __user *) arg);
	case EXT2_IOC_SETFLAGS: {
		unsigned int oldflags;

		ret = mnt_want_write(filp->f_path.mnt);
		if (ret)
			return ret;

		if (!is_owner_or_cap(inode)) {
			ret = -EACCES;
			goto setflags_out;
		}

		if (get_user(flags, (int __user *) arg)) {
			ret = -EFAULT;
			goto setflags_out;
		}

		if (!S_ISDIR(inode->i_mode))
			flags &= ~EXT2_DIRSYNC_FL;

		mutex_lock(&inode->i_mutex);
		/* Is it quota file? Do not allow user to mess with it */
		if (IS_NOQUOTA(inode)) {
			mutex_unlock(&inode->i_mutex);
			ret = -EPERM;
			goto setflags_out;
		}
		oldflags = ei->i_flags;

		/*
		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
		 * the relevant capability.
		 *
		 * This test looks nicer. Thanks to Pauline Middelink
		 */
		if ((flags ^ oldflags) & (EXT2_APPEND_FL | EXT2_IMMUTABLE_FL)) {
			if (!capable(CAP_LINUX_IMMUTABLE)) {
				mutex_unlock(&inode->i_mutex);
				ret = -EPERM;
				goto setflags_out;
			}
		}

		flags = flags & EXT2_FL_USER_MODIFIABLE;
		flags |= oldflags & ~EXT2_FL_USER_MODIFIABLE;
		ei->i_flags = flags;
		mutex_unlock(&inode->i_mutex);

		ext2_set_inode_flags(inode);
		inode->i_ctime = CURRENT_TIME_SEC;
		mark_inode_dirty(inode);
setflags_out:
		mnt_drop_write(filp->f_path.mnt);
		return ret;
	}
	case EXT2_IOC_GETVERSION:
		return put_user(inode->i_generation, (int __user *) arg);
	case EXT2_IOC_SETVERSION:
		if (!is_owner_or_cap(inode))
			return -EPERM;
		ret = mnt_want_write(filp->f_path.mnt);
		if (ret)
			return ret;
		if (get_user(inode->i_generation, (int __user *) arg)) {
			ret = -EFAULT;
		} else {
			inode->i_ctime = CURRENT_TIME_SEC;
			mark_inode_dirty(inode);
		}
		mnt_drop_write(filp->f_path.mnt);
		return ret;
	case EXT2_IOC_GETRSVSZ:
		if (test_opt(inode->i_sb, RESERVATION)
			&& S_ISREG(inode->i_mode)
			&& ei->i_block_alloc_info) {
			rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
			return put_user(rsv_window_size, (int __user *)arg);
		}
		return -ENOTTY;
	case EXT2_IOC_SETRSVSZ: {

		if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
			return -ENOTTY;

		if (!is_owner_or_cap(inode))
			return -EACCES;

		if (get_user(rsv_window_size, (int __user *)arg))
			return -EFAULT;

		ret = mnt_want_write(filp->f_path.mnt);
		if (ret)
			return ret;

		if (rsv_window_size > EXT2_MAX_RESERVE_BLOCKS)
			rsv_window_size = EXT2_MAX_RESERVE_BLOCKS;

		/*
		 * need to allocate reservation structure for this inode
		 * before set the window size
		 */
		/*
		 * XXX What lock should protect the rsv_goal_size?
		 * Accessed in ext2_get_block only.  ext3 uses i_truncate.
		 */
		mutex_lock(&ei->truncate_mutex);
		if (!ei->i_block_alloc_info)
			ext2_init_block_alloc_info(inode);

		if (ei->i_block_alloc_info){
			struct ext2_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
			rsv->rsv_goal_size = rsv_window_size;
		}
		mutex_unlock(&ei->truncate_mutex);
		mnt_drop_write(filp->f_path.mnt);
		return 0;
	}
	default:
		return -ENOTTY;
	}
}

#ifdef CONFIG_COMPAT
long ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	/* These are just misnamed, they actually get/put from/to user an int */
	switch (cmd) {
	case EXT2_IOC32_GETFLAGS:
		cmd = EXT2_IOC_GETFLAGS;
		break;
	case EXT2_IOC32_SETFLAGS:
		cmd = EXT2_IOC_SETFLAGS;
		break;
	case EXT2_IOC32_GETVERSION:
		cmd = EXT2_IOC_GETVERSION;
		break;
	case EXT2_IOC32_SETVERSION:
		cmd = EXT2_IOC_SETVERSION;
		break;
	default:
		return -ENOIOCTLCMD;
	}
	return ext2_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
}
#endif
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/ext2/ioctl.c
	3	*
	4	* Copyright (C) 1993, 1994, 1995
	5	* Remy Card (card@masi.ibp.fr)
	6	* Laboratoire MASI - Institut Blaise Pascal
	7	* Universite Pierre et Marie Curie (Paris VI)
	8	*/
	9
	10	#include "ext2.h"
16f7e0fe	11	#include <linux/capability.h>
1da177e4 LT	12	#include <linux/time.h>
1da177e4 LT	13	#include <linux/sched.h>
e322ff07	14	#include <linux/compat.h>
42a74f20	15	#include <linux/mount.h>
e322ff07	16	#include <linux/smp_lock.h>
1da177e4 LT	17	#include <asm/current.h>
	18	#include <asm/uaccess.h>
	19
	20
14f9f7b2	21	long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1da177e4	22	{
14f9f7b2	23	struct inode *inode = filp->f_dentry->d_inode;
1da177e4 LT	24	struct ext2_inode_info *ei = EXT2_I(inode);
1da177e4 LT	25	unsigned int flags;
a686cd89	26	unsigned short rsv_window_size;
42a74f20	27	int ret;
1da177e4 LT	28
	29	ext2_debug ("cmd = %u, arg = %lu\n", cmd, arg);
	30
	31	switch (cmd) {
	32	case EXT2_IOC_GETFLAGS:
4f99ed67	33	ext2_get_inode_flags(ei);
1da177e4 LT	34	flags = ei->i_flags & EXT2_FL_USER_VISIBLE;
	35	return put_user(flags, (int __user *) arg);
	36	case EXT2_IOC_SETFLAGS: {
	37	unsigned int oldflags;
	38
42a74f20 DH	39	ret = mnt_want_write(filp->f_path.mnt);
	40	if (ret)
	41	return ret;
1da177e4	42
42a74f20 DH	43	if (!is_owner_or_cap(inode)) {
	44	ret = -EACCES;
	45	goto setflags_out;
	46	}
1da177e4	47
42a74f20 DH	48	if (get_user(flags, (int __user *) arg)) {
	49	ret = -EFAULT;
	50	goto setflags_out;
	51	}
1da177e4 LT	52
	53	if (!S_ISDIR(inode->i_mode))
	54	flags &= ~EXT2_DIRSYNC_FL;
	55
93f210dd	56	mutex_lock(&inode->i_mutex);
e47776a0 JK	57	/* Is it quota file? Do not allow user to mess with it */
	58	if (IS_NOQUOTA(inode)) {
	59	mutex_unlock(&inode->i_mutex);
42a74f20 DH	60	ret = -EPERM;
42a74f20 DH	61	goto setflags_out;
e47776a0	62	}
1da177e4 LT	63	oldflags = ei->i_flags;
	64
	65	/*
	66	* The IMMUTABLE and APPEND_ONLY flags can only be changed by
	67	* the relevant capability.
	68	*
	69	* This test looks nicer. Thanks to Pauline Middelink
	70	*/
	71	if ((flags ^ oldflags) & (EXT2_APPEND_FL \| EXT2_IMMUTABLE_FL)) {
93f210dd AM	72	if (!capable(CAP_LINUX_IMMUTABLE)) {
93f210dd AM	73	mutex_unlock(&inode->i_mutex);
42a74f20 DH	74	ret = -EPERM;
42a74f20 DH	75	goto setflags_out;
93f210dd	76	}
1da177e4 LT	77	}
	78
	79	flags = flags & EXT2_FL_USER_MODIFIABLE;
	80	flags \|= oldflags & ~EXT2_FL_USER_MODIFIABLE;
	81	ei->i_flags = flags;
93f210dd	82	mutex_unlock(&inode->i_mutex);
1da177e4 LT	83
	84	ext2_set_inode_flags(inode);
	85	inode->i_ctime = CURRENT_TIME_SEC;
	86	mark_inode_dirty(inode);
42a74f20 DH	87	setflags_out:
	88	mnt_drop_write(filp->f_path.mnt);
	89	return ret;
1da177e4 LT	90	}
	91	case EXT2_IOC_GETVERSION:
	92	return put_user(inode->i_generation, (int __user *) arg);
	93	case EXT2_IOC_SETVERSION:
3bd858ab	94	if (!is_owner_or_cap(inode))
1da177e4	95	return -EPERM;
42a74f20 DH	96	ret = mnt_want_write(filp->f_path.mnt);
	97	if (ret)
	98	return ret;
	99	if (get_user(inode->i_generation, (int __user *) arg)) {
	100	ret = -EFAULT;
	101	} else {
	102	inode->i_ctime = CURRENT_TIME_SEC;
	103	mark_inode_dirty(inode);
	104	}
	105	mnt_drop_write(filp->f_path.mnt);
	106	return ret;
a686cd89 MB	107	case EXT2_IOC_GETRSVSZ:
	108	if (test_opt(inode->i_sb, RESERVATION)
	109	&& S_ISREG(inode->i_mode)
	110	&& ei->i_block_alloc_info) {
	111	rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
	112	return put_user(rsv_window_size, (int __user *)arg);
	113	}
	114	return -ENOTTY;
	115	case EXT2_IOC_SETRSVSZ: {
	116
	117	if (!test_opt(inode->i_sb, RESERVATION) \|\|!S_ISREG(inode->i_mode))
	118	return -ENOTTY;
	119
42a74f20	120	if (!is_owner_or_cap(inode))
a686cd89 MB	121	return -EACCES;
	122
	123	if (get_user(rsv_window_size, (int __user *)arg))
	124	return -EFAULT;
	125
42a74f20 DH	126	ret = mnt_want_write(filp->f_path.mnt);
	127	if (ret)
	128	return ret;
	129
a686cd89 MB	130	if (rsv_window_size > EXT2_MAX_RESERVE_BLOCKS)
	131	rsv_window_size = EXT2_MAX_RESERVE_BLOCKS;
	132
	133	/*
	134	* need to allocate reservation structure for this inode
	135	* before set the window size
	136	*/
	137	/*
	138	* XXX What lock should protect the rsv_goal_size?
	139	* Accessed in ext2_get_block only. ext3 uses i_truncate.
	140	*/
	141	mutex_lock(&ei->truncate_mutex);
	142	if (!ei->i_block_alloc_info)
	143	ext2_init_block_alloc_info(inode);
	144
	145	if (ei->i_block_alloc_info){
	146	struct ext2_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
	147	rsv->rsv_goal_size = rsv_window_size;
	148	}
	149	mutex_unlock(&ei->truncate_mutex);
42a74f20	150	mnt_drop_write(filp->f_path.mnt);
a686cd89 MB	151	return 0;
a686cd89 MB	152	}
1da177e4 LT	153	default:
	154	return -ENOTTY;
	155	}
	156	}
e322ff07 DH	157
	158	#ifdef CONFIG_COMPAT
	159	long ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	160	{
e322ff07 DH	161	/* These are just misnamed, they actually get/put from/to user an int */
	162	switch (cmd) {
	163	case EXT2_IOC32_GETFLAGS:
	164	cmd = EXT2_IOC_GETFLAGS;
	165	break;
	166	case EXT2_IOC32_SETFLAGS:
	167	cmd = EXT2_IOC_SETFLAGS;
	168	break;
	169	case EXT2_IOC32_GETVERSION:
	170	cmd = EXT2_IOC_GETVERSION;
	171	break;
	172	case EXT2_IOC32_SETVERSION:
	173	cmd = EXT2_IOC_SETVERSION;
	174	break;
	175	default:
	176	return -ENOIOCTLCMD;
	177	}
14f9f7b2	178	return ext2_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
e322ff07 DH	179	}
e322ff07 DH	180	#endif