1 // SPDX-License-Identifier: GPL-2.0
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"
12 #include <linux/capability.h>
13 #include <linux/time.h>
14 #include <linux/sched.h>
15 #include <linux/compat.h>
16 #include <linux/mount.h>
17 #include <asm/current.h>
18 #include <linux/uaccess.h>
19 #include <linux/fileattr.h>
20
ext2_fileattr_get(struct dentry * dentry,struct fileattr * fa)21 int ext2_fileattr_get(struct dentry *dentry, struct fileattr *fa)
22 {
23 struct ext2_inode_info *ei = EXT2_I(d_inode(dentry));
24
25 fileattr_fill_flags(fa, ei->i_flags & EXT2_FL_USER_VISIBLE);
26
27 return 0;
28 }
29
ext2_fileattr_set(struct mnt_idmap * idmap,struct dentry * dentry,struct fileattr * fa)30 int ext2_fileattr_set(struct mnt_idmap *idmap,
31 struct dentry *dentry, struct fileattr *fa)
32 {
33 struct inode *inode = d_inode(dentry);
34 struct ext2_inode_info *ei = EXT2_I(inode);
35
36 if (fileattr_has_fsx(fa))
37 return -EOPNOTSUPP;
38
39 /* Is it quota file? Do not allow user to mess with it */
40 if (IS_NOQUOTA(inode))
41 return -EPERM;
42
43 ei->i_flags = (ei->i_flags & ~EXT2_FL_USER_MODIFIABLE) |
44 (fa->flags & EXT2_FL_USER_MODIFIABLE);
45
46 ext2_set_inode_flags(inode);
47 inode_set_ctime_current(inode);
48 mark_inode_dirty(inode);
49
50 return 0;
51 }
52
53
ext2_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)54 long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
55 {
56 struct inode *inode = file_inode(filp);
57 struct ext2_inode_info *ei = EXT2_I(inode);
58 unsigned short rsv_window_size;
59 int ret;
60
61 ext2_debug ("cmd = %u, arg = %lu\n", cmd, arg);
62
63 switch (cmd) {
64 case EXT2_IOC_GETVERSION:
65 return put_user(inode->i_generation, (int __user *) arg);
66 case EXT2_IOC_SETVERSION: {
67 __u32 generation;
68
69 if (!inode_owner_or_capable(&nop_mnt_idmap, inode))
70 return -EPERM;
71 ret = mnt_want_write_file(filp);
72 if (ret)
73 return ret;
74 if (get_user(generation, (int __user *) arg)) {
75 ret = -EFAULT;
76 goto setversion_out;
77 }
78
79 inode_lock(inode);
80 inode_set_ctime_current(inode);
81 inode->i_generation = generation;
82 inode_unlock(inode);
83
84 mark_inode_dirty(inode);
85 setversion_out:
86 mnt_drop_write_file(filp);
87 return ret;
88 }
89 case EXT2_IOC_GETRSVSZ:
90 if (test_opt(inode->i_sb, RESERVATION)
91 && S_ISREG(inode->i_mode)
92 && ei->i_block_alloc_info) {
93 rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
94 return put_user(rsv_window_size, (int __user *)arg);
95 }
96 return -ENOTTY;
97 case EXT2_IOC_SETRSVSZ: {
98
99 if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
100 return -ENOTTY;
101
102 if (!inode_owner_or_capable(&nop_mnt_idmap, inode))
103 return -EACCES;
104
105 if (get_user(rsv_window_size, (int __user *)arg))
106 return -EFAULT;
107
108 ret = mnt_want_write_file(filp);
109 if (ret)
110 return ret;
111
112 if (rsv_window_size > EXT2_MAX_RESERVE_BLOCKS)
113 rsv_window_size = EXT2_MAX_RESERVE_BLOCKS;
114
115 /*
116 * need to allocate reservation structure for this inode
117 * before set the window size
118 */
119 /*
120 * XXX What lock should protect the rsv_goal_size?
121 * Accessed in ext2_get_block only. ext3 uses i_truncate.
122 */
123 mutex_lock(&ei->truncate_mutex);
124 if (!ei->i_block_alloc_info)
125 ext2_init_block_alloc_info(inode);
126
127 if (ei->i_block_alloc_info){
128 struct ext2_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
129 rsv->rsv_goal_size = rsv_window_size;
130 } else {
131 ret = -ENOMEM;
132 }
133
134 mutex_unlock(&ei->truncate_mutex);
135 mnt_drop_write_file(filp);
136 return ret;
137 }
138 default:
139 return -ENOTTY;
140 }
141 }
142
143 #ifdef CONFIG_COMPAT
ext2_compat_ioctl(struct file * file,unsigned int cmd,unsigned long arg)144 long ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
145 {
146 /* These are just misnamed, they actually get/put from/to user an int */
147 switch (cmd) {
148 case EXT2_IOC32_GETVERSION:
149 cmd = EXT2_IOC_GETVERSION;
150 break;
151 case EXT2_IOC32_SETVERSION:
152 cmd = EXT2_IOC_SETVERSION;
153 break;
154 default:
155 return -ENOIOCTLCMD;
156 }
157 return ext2_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
158 }
159 #endif
160