Commit bf396c09 authored Jun 09, 2017 by Kristina Martsenko Committed by Will Deacon Jun 12, 2017

arm64: mm: don't print out page table entries on EL0 faults



When we take a fault from EL0 that can't be handled, we print out the
page table entries associated with the faulting address. This allows
userspace to print out any current page table entries, including kernel
(TTBR1) entries. Exposing kernel mappings like this could pose a
security risk, so don't print out page table information on EL0 faults.
(But still print it out for EL1 faults.) This also follows the same
behaviour as x86, printing out page table entries on kernel mode faults
but not user mode faults.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

parent 67ce16ec

arch/arm64/mm/fault.c

+0 −1

Original line number	Diff line number	Diff line
		@@ -264,7 +264,6 @@ static void __do_user_fault(struct task_struct *tsk, unsigned long addr,
		pr_info("%s[%d]: unhandled %s (%d) at 0x%08lx, esr 0x%03x\n",
		tsk->comm, task_pid_nr(tsk), inf->name, sig,
		addr, esr);
		show_pte(addr);
		__show_regs(regs);
		}

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