From 279eb1d940442ac0599fd107da9944249134e1e2 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Wed, 28 Nov 2018 09:27:04 +0000 Subject: [PATCH] powerpc/mm: Fix reporting of kernel execute faults on the 8xx [ Upstream commit ffca395b11c4a5a6df6d6345f794b0e3d578e2d0 ] On the 8xx, no-execute is set via PPP bits in the PTE. Therefore a no-exec fault generates DSISR_PROTFAULT error bits, not DSISR_NOEXEC_OR_G. This patch adds DSISR_PROTFAULT in the test mask. Fixes: d3ca587404b3 ("powerpc/mm: Fix reporting of kernel execute faults") Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Signed-off-by: Sasha Levin --- arch/powerpc/mm/fault.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index d51cf5f..365526e 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -221,7 +221,9 @@ static int mm_fault_error(struct pt_regs *regs, unsigned long addr, static bool bad_kernel_fault(bool is_exec, unsigned long error_code, unsigned long address) { - if (is_exec && (error_code & (DSISR_NOEXEC_OR_G | DSISR_KEYFAULT))) { + /* NX faults set DSISR_PROTFAULT on the 8xx, DSISR_NOEXEC_OR_G on others */ + if (is_exec && (error_code & (DSISR_NOEXEC_OR_G | DSISR_KEYFAULT | + DSISR_PROTFAULT))) { printk_ratelimited(KERN_CRIT "kernel tried to execute" " exec-protected page (%lx) -" "exploit attempt? (uid: %d)\n", -- 2.7.4