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 <linux/fs.h>
11 #include <linux/ext2_fs.h>
12 #include <linux/sched.h>
13 #include <asm/uaccess.h>
14
15
ext2_ioctl(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)16 int ext2_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,
17 unsigned long arg)
18 {
19 unsigned int flags;
20
21 ext2_debug ("cmd = %u, arg = %lu\n", cmd, arg);
22
23 switch (cmd) {
24 case EXT2_IOC_GETFLAGS:
25 flags = inode->u.ext2_i.i_flags & EXT2_FL_USER_VISIBLE;
26 return put_user(flags, (int *) arg);
27 case EXT2_IOC_SETFLAGS: {
28 unsigned int oldflags;
29
30 if (IS_RDONLY(inode))
31 return -EROFS;
32
33 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
34 return -EACCES;
35
36 if (get_user(flags, (int *) arg))
37 return -EFAULT;
38
39 oldflags = inode->u.ext2_i.i_flags;
40
41 /*
42 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
43 * the relevant capability.
44 *
45 * This test looks nicer. Thanks to Pauline Middelink
46 */
47 if ((flags ^ oldflags) & (EXT2_APPEND_FL | EXT2_IMMUTABLE_FL)) {
48 if (!capable(CAP_LINUX_IMMUTABLE))
49 return -EPERM;
50 }
51
52 flags = flags & EXT2_FL_USER_MODIFIABLE;
53 flags |= oldflags & ~EXT2_FL_USER_MODIFIABLE;
54 inode->u.ext2_i.i_flags = flags;
55
56 ext2_set_inode_flags(inode);
57 inode->i_ctime = CURRENT_TIME;
58 mark_inode_dirty(inode);
59 return 0;
60 }
61 case EXT2_IOC_GETVERSION:
62 return put_user(inode->i_generation, (int *) arg);
63 case EXT2_IOC_SETVERSION:
64 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
65 return -EPERM;
66 if (IS_RDONLY(inode))
67 return -EROFS;
68 if (get_user(inode->i_generation, (int *) arg))
69 return -EFAULT;
70 inode->i_ctime = CURRENT_TIME;
71 mark_inode_dirty(inode);
72 return 0;
73 default:
74 return -ENOTTY;
75 }
76 }
77