Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs

Pull overlayfs updates from Miklos Szeredi:
 "This contains several bug fixes and a new mount option
  'default_permissions' that allows read-only exported NFS
  filesystems to be used as lower layer"

* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: check dentry positiveness in ovl_cleanup_whiteouts()
  ovl: setattr: check permissions before copy-up
  ovl: root: copy attr
  ovl: move super block magic number to magic.h
  ovl: use a minimal buffer in ovl_copy_xattr
  ovl: allow zero size xattr
  ovl: default permissions
This commit is contained in:
Linus Torvalds
2016-01-21 12:20:46 -08:00
6 changed files with 101 additions and 18 deletions

View File

@@ -22,9 +22,9 @@
int ovl_copy_xattr(struct dentry *old, struct dentry *new)
{
ssize_t list_size, size;
char *buf, *name, *value;
int error;
ssize_t list_size, size, value_size = 0;
char *buf, *name, *value = NULL;
int uninitialized_var(error);
if (!old->d_inode->i_op->getxattr ||
!new->d_inode->i_op->getxattr)
@@ -41,29 +41,40 @@ int ovl_copy_xattr(struct dentry *old, struct dentry *new)
if (!buf)
return -ENOMEM;
error = -ENOMEM;
value = kmalloc(XATTR_SIZE_MAX, GFP_KERNEL);
if (!value)
goto out;
list_size = vfs_listxattr(old, buf, list_size);
if (list_size <= 0) {
error = list_size;
goto out_free_value;
goto out;
}
for (name = buf; name < (buf + list_size); name += strlen(name) + 1) {
size = vfs_getxattr(old, name, value, XATTR_SIZE_MAX);
if (size <= 0) {
retry:
size = vfs_getxattr(old, name, value, value_size);
if (size == -ERANGE)
size = vfs_getxattr(old, name, NULL, 0);
if (size < 0) {
error = size;
goto out_free_value;
break;
}
if (size > value_size) {
void *new;
new = krealloc(value, size, GFP_KERNEL);
if (!new) {
error = -ENOMEM;
break;
}
value = new;
value_size = size;
goto retry;
}
error = vfs_setxattr(new, name, value, size, 0);
if (error)
goto out_free_value;
break;
}
out_free_value:
kfree(value);
out:
kfree(buf);