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authorLinus Torvalds <torvalds@linux-foundation.org>2012-01-10 21:46:36 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-01-10 21:46:36 -0800
commit5cd9599bba428762025db6027764f1c59d0b1e1b (patch)
treecb59ea13f6e6de4350ca38338bf9633e89f8418a /security
parente343a895a9f342f239c5e3c5ffc6c0b1707e6244 (diff)
parentd668dc56631da067540b2494d2a1f29ff7b5f15a (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: autofs4: deal with autofs4_write/autofs4_write races autofs4: catatonic_mode vs. notify_daemon race autofs4: autofs4_wait() vs. autofs4_catatonic_mode() race hfsplus: creation of hidden dir on mount can fail block_dev: Suppress bdev_cache_init() kmemleak warninig fix shrink_dcache_parent() livelock coda: switch coda_cnode_make() to sane API as well, clean coda_lookup() coda: deal correctly with allocation failure from coda_cnode_makectl() securityfs: fix object creation races
Diffstat (limited to 'security')
-rw-r--r--security/inode.c191
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 @@
static struct vfsmount *mount;
static int mount_count;
-/*
- * TODO:
- * I think I can get rid of these default_file_ops, but not quite sure...
- */
-static ssize_t default_read_file(struct file *file, char __user *buf,
- size_t count, loff_t *ppos)
-{
- return 0;
-}
-
-static ssize_t default_write_file(struct file *file, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- return count;
-}
-
-static int default_open(struct inode *inode, struct file *file)
-{
- if (inode->i_private)
- file->private_data = inode->i_private;
-
- return 0;
-}
-
-static const struct file_operations default_file_ops = {
- .read = default_read_file,
- .write = default_write_file,
- .open = default_open,
- .llseek = noop_llseek,
-};
-
-static struct inode *get_inode(struct super_block *sb, umode_t mode, dev_t dev)
-{
- struct inode *inode = new_inode(sb);
-
- if (inode) {
- inode->i_ino = get_next_ino();
- inode->i_mode = mode;
- inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
- switch (mode & S_IFMT) {
- default:
- init_special_inode(inode, mode, dev);
- break;
- case S_IFREG:
- inode->i_fop = &default_file_ops;
- break;
- case S_IFDIR:
- inode->i_op = &simple_dir_inode_operations;
- inode->i_fop = &simple_dir_operations;
-
- /* directory inodes start off with i_nlink == 2 (for "." entry) */
- inc_nlink(inode);
- break;
- }
- }
- return inode;
-}
-
-/* SMP-safe */
-static int mknod(struct inode *dir, struct dentry *dentry,
- umode_t mode, dev_t dev)
-{
- struct inode *inode;
- int error = -ENOMEM;
-
- if (dentry->d_inode)
- return -EEXIST;
-
- inode = get_inode(dir->i_sb, mode, dev);
- if (inode) {
- d_instantiate(dentry, inode);
- dget(dentry);
- error = 0;
- }
- return error;
-}
-
-static int mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
-{
- int res;
-
- mode = (mode & (S_IRWXUGO | S_ISVTX)) | S_IFDIR;
- res = mknod(dir, dentry, mode, 0);
- if (!res)
- inc_nlink(dir);
- return res;
-}
-
-static int create(struct inode *dir, struct dentry *dentry, umode_t mode)
-{
- mode = (mode & S_IALLUGO) | S_IFREG;
- return mknod(dir, dentry, mode, 0);
-}
-
static inline int positive(struct dentry *dentry)
{
return dentry->d_inode && !d_unhashed(dentry);
@@ -145,38 +51,6 @@ static struct file_system_type fs_type = {
.kill_sb = kill_litter_super,
};
-static int create_by_name(const char *name, umode_t mode,
- struct dentry *parent,
- struct dentry **dentry)
-{
- int error = 0;
-
- *dentry = NULL;
-
- /* If the parent is not specified, we create it in the root.
- * We need the root dentry to do this, which is in the super
- * block. A pointer to that is in the struct vfsmount that we
- * have around.
- */
- if (!parent)
- parent = mount->mnt_root;
-
- mutex_lock(&parent->d_inode->i_mutex);
- *dentry = lookup_one_len(name, parent, strlen(name));
- if (!IS_ERR(*dentry)) {
- if (S_ISDIR(mode))
- error = mkdir(parent->d_inode, *dentry, mode);
- else
- error = create(parent->d_inode, *dentry, mode);
- if (error)
- dput(*dentry);
- } else
- error = PTR_ERR(*dentry);
- mutex_unlock(&parent->d_inode->i_mutex);
-
- return error;
-}
-
/**
* securityfs_create_file - create a file in the securityfs filesystem
*
@@ -209,31 +83,66 @@ struct dentry *securityfs_create_file(const char *name, umode_t mode,
struct dentry *parent, void *data,
const struct file_operations *fops)
{
- struct dentry *dentry = NULL;
+ struct dentry *dentry;
+ int is_dir = S_ISDIR(mode);
+ struct inode *dir, *inode;
int error;
+ if (!is_dir) {
+ BUG_ON(!fops);
+ mode = (mode & S_IALLUGO) | S_IFREG;
+ }
+
pr_debug("securityfs: creating file '%s'\n",name);
error = simple_pin_fs(&fs_type, &mount, &mount_count);
- if (error) {
- dentry = ERR_PTR(error);
- goto exit;
+ if (error)
+ return ERR_PTR(error);
+
+ if (!parent)
+ parent = mount->mnt_root;
+
+ dir = parent->d_inode;
+
+ mutex_lock(&dir->i_mutex);
+ dentry = lookup_one_len(name, parent, strlen(name));
+ if (IS_ERR(dentry))
+ goto out;
+
+ if (dentry->d_inode) {
+ error = -EEXIST;
+ goto out1;
}
- error = create_by_name(name, mode, parent, &dentry);
- if (error) {
- dentry = ERR_PTR(error);
- simple_release_fs(&mount, &mount_count);
- goto exit;
+ inode = new_inode(dir->i_sb);
+ if (!inode) {
+ error = -ENOMEM;
+ goto out1;
}
- if (dentry->d_inode) {
- if (fops)
- dentry->d_inode->i_fop = fops;
- if (data)
- dentry->d_inode->i_private = data;
+ inode->i_ino = get_next_ino();
+ inode->i_mode = mode;
+ inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+ inode->i_private = data;
+ if (is_dir) {
+ inode->i_op = &simple_dir_inode_operations;
+ inode->i_fop = &simple_dir_operations;
+ inc_nlink(inode);
+ inc_nlink(dir);
+ } else {
+ inode->i_fop = fops;
}
-exit:
+ d_instantiate(dentry, inode);
+ dget(dentry);
+ mutex_unlock(&dir->i_mutex);
+ return dentry;
+
+out1:
+ dput(dentry);
+ dentry = ERR_PTR(error);
+out:
+ mutex_unlock(&dir->i_mutex);
+ simple_release_fs(&mount, &mount_count);
return dentry;
}
EXPORT_SYMBOL_GPL(securityfs_create_file);