[linux-block.git] / fs / ext2 / ioctl.c

// SPDX-License-Identifier: GPL-2.0
/*
 * 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 <asm/current.h>
#include <linux/uaccess.h>


long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	struct inode *inode = file_inode(filp);
	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:
		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_file(filp);
		if (ret)
			return ret;

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

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

		flags = ext2_mask_flags(inode->i_mode, flags);

		inode_lock(inode);
		/* Is it quota file? Do not allow user to mess with it */
		if (IS_NOQUOTA(inode)) {
			inode_unlock(inode);
			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)) {
				inode_unlock(inode);
				ret = -EPERM;
				goto setflags_out;
			}
		}

		flags = flags & EXT2_FL_USER_MODIFIABLE;
		flags |= oldflags & ~EXT2_FL_USER_MODIFIABLE;
		ei->i_flags = flags;

		ext2_set_inode_flags(inode);
		inode->i_ctime = current_time(inode);
		inode_unlock(inode);

		mark_inode_dirty(inode);
setflags_out:
		mnt_drop_write_file(filp);
		return ret;
	}
	case EXT2_IOC_GETVERSION:
		return put_user(inode->i_generation, (int __user *) arg);
	case EXT2_IOC_SETVERSION: {
		__u32 generation;

		if (!inode_owner_or_capable(inode))
			return -EPERM;
		ret = mnt_want_write_file(filp);
		if (ret)
			return ret;
		if (get_user(generation, (int __user *) arg)) {
			ret = -EFAULT;
			goto setversion_out;
		}

		inode_lock(inode);
		inode->i_ctime = current_time(inode);
		inode->i_generation = generation;
		inode_unlock(inode);

		mark_inode_dirty(inode);
setversion_out:
		mnt_drop_write_file(filp);
		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 (!inode_owner_or_capable(inode))
			return -EACCES;

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

		ret = mnt_want_write_file(filp);
		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_file(filp);
		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
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* linux/fs/ext2/ioctl.c
	4	*
	5	* Copyright (C) 1993, 1994, 1995
	6	* Remy Card (card@masi.ibp.fr)
	7	* Laboratoire MASI - Institut Blaise Pascal
	8	* Universite Pierre et Marie Curie (Paris VI)
	9	*/
	10
	11	#include "ext2.h"
16f7e0fe	12	#include <linux/capability.h>
1da177e4 LT	13	#include <linux/time.h>
1da177e4 LT	14	#include <linux/sched.h>
e322ff07	15	#include <linux/compat.h>
42a74f20	16	#include <linux/mount.h>
1da177e4	17	#include <asm/current.h>
7c0f6ba6	18	#include <linux/uaccess.h>
1da177e4 LT	19
1da177e4 LT	20
14f9f7b2	21	long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1da177e4	22	{
496ad9aa	23	struct inode *inode = file_inode(filp);
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:
	33	flags = ei->i_flags & EXT2_FL_USER_VISIBLE;
	34	return put_user(flags, (int __user *) arg);
	35	case EXT2_IOC_SETFLAGS: {
	36	unsigned int oldflags;
	37
a561be71	38	ret = mnt_want_write_file(filp);
42a74f20 DH	39	if (ret)
42a74f20 DH	40	return ret;
1da177e4	41
2e149670	42	if (!inode_owner_or_capable(inode)) {
42a74f20 DH	43	ret = -EACCES;
	44	goto setflags_out;
	45	}
1da177e4	46
42a74f20 DH	47	if (get_user(flags, (int __user *) arg)) {
	48	ret = -EFAULT;
	49	goto setflags_out;
	50	}
1da177e4	51
ef8b6461	52	flags = ext2_mask_flags(inode->i_mode, flags);
1da177e4	53
5955102c	54	inode_lock(inode);
e47776a0 JK	55	/* Is it quota file? Do not allow user to mess with it */
e47776a0 JK	56	if (IS_NOQUOTA(inode)) {
5955102c	57	inode_unlock(inode);
42a74f20 DH	58	ret = -EPERM;
42a74f20 DH	59	goto setflags_out;
e47776a0	60	}
1da177e4 LT	61	oldflags = ei->i_flags;
	62
	63	/*
	64	* The IMMUTABLE and APPEND_ONLY flags can only be changed by
	65	* the relevant capability.
	66	*
	67	* This test looks nicer. Thanks to Pauline Middelink
	68	*/
	69	if ((flags ^ oldflags) & (EXT2_APPEND_FL \| EXT2_IMMUTABLE_FL)) {
93f210dd	70	if (!capable(CAP_LINUX_IMMUTABLE)) {
5955102c	71	inode_unlock(inode);
42a74f20 DH	72	ret = -EPERM;
42a74f20 DH	73	goto setflags_out;
93f210dd	74	}
1da177e4 LT	75	}
	76
	77	flags = flags & EXT2_FL_USER_MODIFIABLE;
	78	flags \|= oldflags & ~EXT2_FL_USER_MODIFIABLE;
	79	ei->i_flags = flags;
	80
	81	ext2_set_inode_flags(inode);
02027d42	82	inode->i_ctime = current_time(inode);
5955102c	83	inode_unlock(inode);
34b07840	84
1da177e4	85	mark_inode_dirty(inode);
42a74f20	86	setflags_out:
2a79f17e	87	mnt_drop_write_file(filp);
42a74f20	88	return ret;
1da177e4 LT	89	}
	90	case EXT2_IOC_GETVERSION:
	91	return put_user(inode->i_generation, (int __user *) arg);
34b07840 DH	92	case EXT2_IOC_SETVERSION: {
	93	__u32 generation;
	94
2e149670	95	if (!inode_owner_or_capable(inode))
1da177e4	96	return -EPERM;
a561be71	97	ret = mnt_want_write_file(filp);
42a74f20 DH	98	if (ret)
42a74f20 DH	99	return ret;
34b07840	100	if (get_user(generation, (int __user *) arg)) {
42a74f20	101	ret = -EFAULT;
34b07840	102	goto setversion_out;
42a74f20	103	}
34b07840	104
5955102c	105	inode_lock(inode);
02027d42	106	inode->i_ctime = current_time(inode);
34b07840	107	inode->i_generation = generation;
5955102c	108	inode_unlock(inode);
34b07840 DH	109
	110	mark_inode_dirty(inode);
	111	setversion_out:
2a79f17e	112	mnt_drop_write_file(filp);
42a74f20	113	return ret;
34b07840	114	}
a686cd89 MB	115	case EXT2_IOC_GETRSVSZ:
	116	if (test_opt(inode->i_sb, RESERVATION)
	117	&& S_ISREG(inode->i_mode)
	118	&& ei->i_block_alloc_info) {
	119	rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
	120	return put_user(rsv_window_size, (int __user *)arg);
	121	}
	122	return -ENOTTY;
	123	case EXT2_IOC_SETRSVSZ: {
	124
	125	if (!test_opt(inode->i_sb, RESERVATION) \|\|!S_ISREG(inode->i_mode))
	126	return -ENOTTY;
	127
2e149670	128	if (!inode_owner_or_capable(inode))
a686cd89 MB	129	return -EACCES;
	130
	131	if (get_user(rsv_window_size, (int __user *)arg))
	132	return -EFAULT;
	133
a561be71	134	ret = mnt_want_write_file(filp);
42a74f20 DH	135	if (ret)
	136	return ret;
	137
a686cd89 MB	138	if (rsv_window_size > EXT2_MAX_RESERVE_BLOCKS)
	139	rsv_window_size = EXT2_MAX_RESERVE_BLOCKS;
	140
	141	/*
	142	* need to allocate reservation structure for this inode
	143	* before set the window size
	144	*/
	145	/*
	146	* XXX What lock should protect the rsv_goal_size?
	147	* Accessed in ext2_get_block only. ext3 uses i_truncate.
	148	*/
	149	mutex_lock(&ei->truncate_mutex);
	150	if (!ei->i_block_alloc_info)
	151	ext2_init_block_alloc_info(inode);
	152
	153	if (ei->i_block_alloc_info){
	154	struct ext2_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
	155	rsv->rsv_goal_size = rsv_window_size;
	156	}
	157	mutex_unlock(&ei->truncate_mutex);
2a79f17e	158	mnt_drop_write_file(filp);
a686cd89 MB	159	return 0;
a686cd89 MB	160	}
1da177e4 LT	161	default:
	162	return -ENOTTY;
	163	}
	164	}
e322ff07 DH	165
	166	#ifdef CONFIG_COMPAT
	167	long ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	168	{
e322ff07 DH	169	/* These are just misnamed, they actually get/put from/to user an int */
	170	switch (cmd) {
	171	case EXT2_IOC32_GETFLAGS:
	172	cmd = EXT2_IOC_GETFLAGS;
	173	break;
	174	case EXT2_IOC32_SETFLAGS:
	175	cmd = EXT2_IOC_SETFLAGS;
	176	break;
	177	case EXT2_IOC32_GETVERSION:
	178	cmd = EXT2_IOC_GETVERSION;
	179	break;
	180	case EXT2_IOC32_SETVERSION:
	181	cmd = EXT2_IOC_SETVERSION;
	182	break;
	183	default:
	184	return -ENOIOCTLCMD;
	185	}
14f9f7b2	186	return ext2_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
e322ff07 DH	187	}
e322ff07 DH	188	#endif