xref: /openbmc/linux/fs/ext2/ioctl.c (revision d5cb9783536a41df9f9cba5b0a1d78047ed787f7)
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"
11 #include <linux/time.h>
12 #include <linux/sched.h>
13 #include <asm/current.h>
14 #include <asm/uaccess.h>
15 
16 
17 int ext2_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,
18 		unsigned long arg)
19 {
20 	struct ext2_inode_info *ei = EXT2_I(inode);
21 	unsigned int flags;
22 
23 	ext2_debug ("cmd = %u, arg = %lu\n", cmd, arg);
24 
25 	switch (cmd) {
26 	case EXT2_IOC_GETFLAGS:
27 		flags = ei->i_flags & EXT2_FL_USER_VISIBLE;
28 		return put_user(flags, (int __user *) arg);
29 	case EXT2_IOC_SETFLAGS: {
30 		unsigned int oldflags;
31 
32 		if (IS_RDONLY(inode))
33 			return -EROFS;
34 
35 		if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
36 			return -EACCES;
37 
38 		if (get_user(flags, (int __user *) arg))
39 			return -EFAULT;
40 
41 		if (!S_ISDIR(inode->i_mode))
42 			flags &= ~EXT2_DIRSYNC_FL;
43 
44 		oldflags = ei->i_flags;
45 
46 		/*
47 		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
48 		 * the relevant capability.
49 		 *
50 		 * This test looks nicer. Thanks to Pauline Middelink
51 		 */
52 		if ((flags ^ oldflags) & (EXT2_APPEND_FL | EXT2_IMMUTABLE_FL)) {
53 			if (!capable(CAP_LINUX_IMMUTABLE))
54 				return -EPERM;
55 		}
56 
57 		flags = flags & EXT2_FL_USER_MODIFIABLE;
58 		flags |= oldflags & ~EXT2_FL_USER_MODIFIABLE;
59 		ei->i_flags = flags;
60 
61 		ext2_set_inode_flags(inode);
62 		inode->i_ctime = CURRENT_TIME_SEC;
63 		mark_inode_dirty(inode);
64 		return 0;
65 	}
66 	case EXT2_IOC_GETVERSION:
67 		return put_user(inode->i_generation, (int __user *) arg);
68 	case EXT2_IOC_SETVERSION:
69 		if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
70 			return -EPERM;
71 		if (IS_RDONLY(inode))
72 			return -EROFS;
73 		if (get_user(inode->i_generation, (int __user *) arg))
74 			return -EFAULT;
75 		inode->i_ctime = CURRENT_TIME_SEC;
76 		mark_inode_dirty(inode);
77 		return 0;
78 	default:
79 		return -ENOTTY;
80 	}
81 }
82