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 20 21 long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 22 { 23 struct inode *inode = file_inode(filp); 24 struct ext2_inode_info *ei = EXT2_I(inode); 25 unsigned int flags; 26 unsigned short rsv_window_size; 27 int ret; 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 38 ret = mnt_want_write_file(filp); 39 if (ret) 40 return ret; 41 42 if (!inode_owner_or_capable(inode)) { 43 ret = -EACCES; 44 goto setflags_out; 45 } 46 47 if (get_user(flags, (int __user *) arg)) { 48 ret = -EFAULT; 49 goto setflags_out; 50 } 51 52 flags = ext2_mask_flags(inode->i_mode, flags); 53 54 inode_lock(inode); 55 /* Is it quota file? Do not allow user to mess with it */ 56 if (IS_NOQUOTA(inode)) { 57 inode_unlock(inode); 58 ret = -EPERM; 59 goto setflags_out; 60 } 61 oldflags = ei->i_flags; 62 63 ret = vfs_ioc_setflags_prepare(inode, oldflags, flags); 64 if (ret) { 65 inode_unlock(inode); 66 goto setflags_out; 67 } 68 69 flags = flags & EXT2_FL_USER_MODIFIABLE; 70 flags |= oldflags & ~EXT2_FL_USER_MODIFIABLE; 71 ei->i_flags = flags; 72 73 ext2_set_inode_flags(inode); 74 inode->i_ctime = current_time(inode); 75 inode_unlock(inode); 76 77 mark_inode_dirty(inode); 78 setflags_out: 79 mnt_drop_write_file(filp); 80 return ret; 81 } 82 case EXT2_IOC_GETVERSION: 83 return put_user(inode->i_generation, (int __user *) arg); 84 case EXT2_IOC_SETVERSION: { 85 __u32 generation; 86 87 if (!inode_owner_or_capable(inode)) 88 return -EPERM; 89 ret = mnt_want_write_file(filp); 90 if (ret) 91 return ret; 92 if (get_user(generation, (int __user *) arg)) { 93 ret = -EFAULT; 94 goto setversion_out; 95 } 96 97 inode_lock(inode); 98 inode->i_ctime = current_time(inode); 99 inode->i_generation = generation; 100 inode_unlock(inode); 101 102 mark_inode_dirty(inode); 103 setversion_out: 104 mnt_drop_write_file(filp); 105 return ret; 106 } 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; 119 120 if (!inode_owner_or_capable(inode)) 121 return -EACCES; 122 123 if (get_user(rsv_window_size, (int __user *)arg)) 124 return -EFAULT; 125 126 ret = mnt_want_write_file(filp); 127 if (ret) 128 return ret; 129 130 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); 150 mnt_drop_write_file(filp); 151 return 0; 152 } 153 default: 154 return -ENOTTY; 155 } 156 } 157 158 #ifdef CONFIG_COMPAT 159 long ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 160 { 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 } 178 return ext2_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); 179 } 180 #endif 181