Commit 83a35114 authored May 27, 2015 by Rusty Russell Committed by Linus Torvalds May 27, 2015

lguest: fix out-by-one error in address checking.



This bug has been there since day 1; addresses in the top guest physical
page weren't considered valid.  You could map that page (the check in
check_gpte() is correct), but if a guest tried to put a pagetable there
we'd check that address manually when walking it, and kill the guest.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 3cfd4ba7

drivers/lguest/core.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -173,7 +173,7 @@ static void unmap_switcher(void)
		bool lguest_address_ok(const struct lguest *lg,
		unsigned long addr, unsigned long len)
		{
		return (addr+len) / PAGE_SIZE < lg->pfn_limit && (addr+len >= addr);
		return addr+len <= lg->pfn_limit * PAGE_SIZE && (addr+len >= addr);
		}

		/*