Messages in this thread | | | Date | Tue, 06 Aug 2002 02:28:13 -0700 (PDT) | Subject | Re: [TRIVIAL] Warn users about machines with non-working WP bit | From | "David S. Miller" <> |
| |
From: Manfred Spraul <manfred@colorfullife.com> Date: Tue, 06 Aug 2002 11:17:33 +0200
> - printk("No.\n"); > + printk("No (that's security hole).\n"); > #ifdef CONFIG_X86_WP_WORKS_OK Could you explain the hole? WP works for user space apps, only ring0 (or ring 0-2?) code ignores the WP bit on i386.
So copy_to_user() could write to user areas that are write-proteced.
verify_area() checks aren't enough, consider a threaded application calling mprotect() while the copy is in progress. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |