On Wednesday, November 05, 2014 03:42:28 PM David Howells wrote: > Provide two new security hooks for use with security files that are used > when a file is copied up between layers: > > (1) security_inode_copy_up(). This is called so that the security label on > the destination file can be set appropriately. > > (2) security_inode_copy_up_xattr(). This is called so that each xattr > being copied up can be vetted - including modification and discard. This didn't occur to me earlier, but we may want to pick a different phrase to use instead of "copy_up" as that has a special meaning for some security/MLS folks (although strangely enough, I suspect most of these copy-on-write operations will be "copy up" in the MLS sense of the word). How about "security_inode_copy_overlay" or something like that? > + * @inode_copy_up_xattr: > + * Filter/modify the xattrs being copied up when a unioned file is > ...copied > + * up from a lower layer to the union/overlay layer. > + * @src indicates the file that is being copied up. > + * @dst indicates the file that has being created by the copy up. > + * @name indicates the name of the xattr. > + * @value, *@size indicate the payload of the xattr. > + * Returns 0 to accept the xattr, 1 to discard the xattr or a negative > + * error code to abort the copy up. The xattr buffer must be at least > + * XATTR_SIZE_MAX in capacity and the contents may be modified and > ....*@size > + * changed appropriately. Just so I'm clean, if the LSM wanted to modify the xattr it would modify @value/@size and return 0? -- paul moore www.paul-moore.com -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
