diff options
Diffstat (limited to 'security/inode.c')
| -rw-r--r-- | security/inode.c | 191 |
1 files changed, 50 insertions, 141 deletions
diff --git a/security/inode.c b/security/inode.c index 90a70a67d835..43ce6e19015f 100644 --- a/security/inode.c +++ b/security/inode.c | |||
| @@ -25,100 +25,6 @@ | |||
| 25 | static struct vfsmount *mount; | 25 | static struct vfsmount *mount; |
| 26 | static int mount_count; | 26 | static int mount_count; |
| 27 | 27 | ||
| 28 | /* | ||
| 29 | * TODO: | ||
| 30 | * I think I can get rid of these default_file_ops, but not quite sure... | ||
| 31 | */ | ||
| 32 | static ssize_t default_read_file(struct file *file, char __user *buf, | ||
| 33 | size_t count, loff_t *ppos) | ||
| 34 | { | ||
| 35 | return 0; | ||
| 36 | } | ||
| 37 | |||
| 38 | static ssize_t default_write_file(struct file *file, const char __user *buf, | ||
| 39 | size_t count, loff_t *ppos) | ||
| 40 | { | ||
| 41 | return count; | ||
| 42 | } | ||
| 43 | |||
| 44 | static int default_open(struct inode *inode, struct file *file) | ||
| 45 | { | ||
| 46 | if (inode->i_private) | ||
| 47 | file->private_data = inode->i_private; | ||
| 48 | |||
| 49 | return 0; | ||
| 50 | } | ||
| 51 | |||
| 52 | static const struct file_operations default_file_ops = { | ||
| 53 | .read = default_read_file, | ||
| 54 | .write = default_write_file, | ||
| 55 | .open = default_open, | ||
| 56 | .llseek = noop_llseek, | ||
| 57 | }; | ||
| 58 | |||
| 59 | static struct inode *get_inode(struct super_block *sb, umode_t mode, dev_t dev) | ||
| 60 | { | ||
| 61 | struct inode *inode = new_inode(sb); | ||
| 62 | |||
| 63 | if (inode) { | ||
| 64 | inode->i_ino = get_next_ino(); | ||
| 65 | inode->i_mode = mode; | ||
| 66 | inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; | ||
| 67 | switch (mode & S_IFMT) { | ||
| 68 | default: | ||
| 69 | init_special_inode(inode, mode, dev); | ||
| 70 | break; | ||
| 71 | case S_IFREG: | ||
| 72 | inode->i_fop = &default_file_ops; | ||
| 73 | break; | ||
| 74 | case S_IFDIR: | ||
| 75 | inode->i_op = &simple_dir_inode_operations; | ||
| 76 | inode->i_fop = &simple_dir_operations; | ||
| 77 | |||
| 78 | /* directory inodes start off with i_nlink == 2 (for "." entry) */ | ||
| 79 | inc_nlink(inode); | ||
| 80 | break; | ||
| 81 | } | ||
| 82 | } | ||
| 83 | return inode; | ||
| 84 | } | ||
| 85 | |||
| 86 | /* SMP-safe */ | ||
| 87 | static int mknod(struct inode *dir, struct dentry *dentry, | ||
| 88 | umode_t mode, dev_t dev) | ||
| 89 | { | ||
| 90 | struct inode *inode; | ||
| 91 | int error = -ENOMEM; | ||
| 92 | |||
| 93 | if (dentry->d_inode) | ||
| 94 | return -EEXIST; | ||
| 95 | |||
| 96 | inode = get_inode(dir->i_sb, mode, dev); | ||
| 97 | if (inode) { | ||
| 98 | d_instantiate(dentry, inode); | ||
| 99 | dget(dentry); | ||
| 100 | error = 0; | ||
| 101 | } | ||
| 102 | return error; | ||
| 103 | } | ||
| 104 | |||
| 105 | static int mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) | ||
| 106 | { | ||
| 107 | int res; | ||
| 108 | |||
| 109 | mode = (mode & (S_IRWXUGO | S_ISVTX)) | S_IFDIR; | ||
| 110 | res = mknod(dir, dentry, mode, 0); | ||
| 111 | if (!res) | ||
| 112 | inc_nlink(dir); | ||
| 113 | return res; | ||
| 114 | } | ||
| 115 | |||
| 116 | static int create(struct inode *dir, struct dentry *dentry, umode_t mode) | ||
| 117 | { | ||
| 118 | mode = (mode & S_IALLUGO) | S_IFREG; | ||
| 119 | return mknod(dir, dentry, mode, 0); | ||
| 120 | } | ||
| 121 | |||
| 122 | static inline int positive(struct dentry *dentry) | 28 | static inline int positive(struct dentry *dentry) |
| 123 | { | 29 | { |
| 124 | return dentry->d_inode && !d_unhashed(dentry); | 30 | return dentry->d_inode && !d_unhashed(dentry); |
| @@ -145,38 +51,6 @@ static struct file_system_type fs_type = { | |||
| 145 | .kill_sb = kill_litter_super, | 51 | .kill_sb = kill_litter_super, |
| 146 | }; | 52 | }; |
| 147 | 53 | ||
| 148 | static int create_by_name(const char *name, umode_t mode, | ||
| 149 | struct dentry *parent, | ||
| 150 | struct dentry **dentry) | ||
| 151 | { | ||
| 152 | int error = 0; | ||
| 153 | |||
| 154 | *dentry = NULL; | ||
| 155 | |||
| 156 | /* If the parent is not specified, we create it in the root. | ||
| 157 | * We need the root dentry to do this, which is in the super | ||
| 158 | * block. A pointer to that is in the struct vfsmount that we | ||
| 159 | * have around. | ||
| 160 | */ | ||
| 161 | if (!parent) | ||
| 162 | parent = mount->mnt_root; | ||
| 163 | |||
| 164 | mutex_lock(&parent->d_inode->i_mutex); | ||
| 165 | *dentry = lookup_one_len(name, parent, strlen(name)); | ||
| 166 | if (!IS_ERR(*dentry)) { | ||
| 167 | if (S_ISDIR(mode)) | ||
| 168 | error = mkdir(parent->d_inode, *dentry, mode); | ||
| 169 | else | ||
| 170 | error = create(parent->d_inode, *dentry, mode); | ||
| 171 | if (error) | ||
| 172 | dput(*dentry); | ||
| 173 | } else | ||
| 174 | error = PTR_ERR(*dentry); | ||
| 175 | mutex_unlock(&parent->d_inode->i_mutex); | ||
| 176 | |||
| 177 | return error; | ||
| 178 | } | ||
| 179 | |||
| 180 | /** | 54 | /** |
| 181 | * securityfs_create_file - create a file in the securityfs filesystem | 55 | * securityfs_create_file - create a file in the securityfs filesystem |
| 182 | * | 56 | * |
| @@ -209,31 +83,66 @@ struct dentry *securityfs_create_file(const char *name, umode_t mode, | |||
| 209 | struct dentry *parent, void *data, | 83 | struct dentry *parent, void *data, |
| 210 | const struct file_operations *fops) | 84 | const struct file_operations *fops) |
| 211 | { | 85 | { |
| 212 | struct dentry *dentry = NULL; | 86 | struct dentry *dentry; |
| 87 | int is_dir = S_ISDIR(mode); | ||
| 88 | struct inode *dir, *inode; | ||
| 213 | int error; | 89 | int error; |
| 214 | 90 | ||
| 91 | if (!is_dir) { | ||
| 92 | BUG_ON(!fops); | ||
| 93 | mode = (mode & S_IALLUGO) | S_IFREG; | ||
| 94 | } | ||
| 95 | |||
| 215 | pr_debug("securityfs: creating file '%s'\n",name); | 96 | pr_debug("securityfs: creating file '%s'\n",name); |
| 216 | 97 | ||
| 217 | error = simple_pin_fs(&fs_type, &mount, &mount_count); | 98 | error = simple_pin_fs(&fs_type, &mount, &mount_count); |
| 218 | if (error) { | 99 | if (error) |
| 219 | dentry = ERR_PTR(error); | 100 | return ERR_PTR(error); |
| 220 | goto exit; | 101 | |
| 102 | if (!parent) | ||
| 103 | parent = mount->mnt_root; | ||
| 104 | |||
| 105 | dir = parent->d_inode; | ||
| 106 | |||
| 107 | mutex_lock(&dir->i_mutex); | ||
| 108 | dentry = lookup_one_len(name, parent, strlen(name)); | ||
| 109 | if (IS_ERR(dentry)) | ||
| 110 | goto out; | ||
| 111 | |||
| 112 | if (dentry->d_inode) { | ||
| 113 | error = -EEXIST; | ||
| 114 | goto out1; | ||
| 221 | } | 115 | } |
| 222 | 116 | ||
| 223 | error = create_by_name(name, mode, parent, &dentry); | 117 | inode = new_inode(dir->i_sb); |
| 224 | if (error) { | 118 | if (!inode) { |
| 225 | dentry = ERR_PTR(error); | 119 | error = -ENOMEM; |
| 226 | simple_release_fs(&mount, &mount_count); | 120 | goto out1; |
| 227 | goto exit; | ||
| 228 | } | 121 | } |
| 229 | 122 | ||
| 230 | if (dentry->d_inode) { | 123 | inode->i_ino = get_next_ino(); |
| 231 | if (fops) | 124 | inode->i_mode = mode; |
| 232 | dentry->d_inode->i_fop = fops; | 125 | inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; |
| 233 | if (data) | 126 | inode->i_private = data; |
| 234 | dentry->d_inode->i_private = data; | 127 | if (is_dir) { |
| 128 | inode->i_op = &simple_dir_inode_operations; | ||
| 129 | inode->i_fop = &simple_dir_operations; | ||
| 130 | inc_nlink(inode); | ||
| 131 | inc_nlink(dir); | ||
| 132 | } else { | ||
| 133 | inode->i_fop = fops; | ||
| 235 | } | 134 | } |
| 236 | exit: | 135 | d_instantiate(dentry, inode); |
| 136 | dget(dentry); | ||
| 137 | mutex_unlock(&dir->i_mutex); | ||
| 138 | return dentry; | ||
| 139 | |||
| 140 | out1: | ||
| 141 | dput(dentry); | ||
| 142 | dentry = ERR_PTR(error); | ||
| 143 | out: | ||
| 144 | mutex_unlock(&dir->i_mutex); | ||
| 145 | simple_release_fs(&mount, &mount_count); | ||
| 237 | return dentry; | 146 | return dentry; |
| 238 | } | 147 | } |
| 239 | EXPORT_SYMBOL_GPL(securityfs_create_file); | 148 | EXPORT_SYMBOL_GPL(securityfs_create_file); |
