Commit 284e6d39 authored by Richard Weinberger's avatar Richard Weinberger
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um: Ensure that a stub page cannot get unmapped 



Trinity discovered an execution path such that a task
can unmap his stub page.

Reported-by: default avatarToralf Förster <toralf.foerster@gmx.de>
Signed-off-by: default avatarRichard Weinberger <richard@nod.at>
parent ae5db6d1

arch/um/kernel/tlb.c

+3 −0
Original line number Diff line number Diff line
@@ -124,6 +124,9 @@ static int add_munmap(unsigned long addr, unsigned long len, 
	struct host_vm_op *last;

	int ret = 0;



	if ((addr >= STUB_START) && (addr < STUB_END))

		return -EINVAL;



	if (hvc->index != 0) {

		last = &hvc->ops[hvc->index - 1];

		if ((last->type == MUNMAP) &&