Cc experts Johannes, Hugh, On 03/12/2013 07:57 AM, Luigi Semenzato wrote:
Greetings linux-mmers, before we can fully deploy zram, we must ensure it conforms to the Chrome OS security requirements. In particular, we do not want to allow user space to read/write the swap device---not even root-owned processes. A similar restriction is available for /dev/mem under CONFIG_STRICT_DEVMEM. There are a few possible approaches to this, but before we go ahead I'd like to ask if anything has happened or is planned in this direction. Otherwise, one idea I am playing with is to add a CONFIG_STRICT_SWAP option that would do this for any swap device (i.e. not specific to zram) and possibly also when swapping to a file. We would add an "internal" open flag, O_KERN_SWAP, as well as clean up a little bit the FMODE_NONOTIFY confusion by adding the kernel flag O_KERN_NONOTIFY and formalizing the sets of external (O_*) and internal (O_KERN_*) open flags. Swapon() and swapoff() would use O_KERN_SWAP internally, and a device opened with that flag would reject user-level opens. Thank you in advance for any input/suggestion! Luigi -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
-- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>