[PATCH v3 06/11] arm64: mm: Mark executable text as guarded pages

Mark Brown
2020-05-06T19:53:30Z

When the kernel is built for BTI and running on a system which supports
make all executable text guarded pages to ensure that loadable module
and JITed BPF code is protected by BTI.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
---
arch/arm64/mm/pageattr.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
index 250c49008d73..bde08090b838 100644
--- a/arch/arm64/mm/pageattr.c
+++ b/arch/arm64/mm/pageattr.c
@@ -126,13 +126,13 @@ int set_memory_nx(unsigned long addr, int numpages)
{
return change_memory_common(addr, numpages,
__pgprot(PTE_PXN),
- __pgprot(0));
+ __pgprot(PTE_MAYBE_GP));
}

int set_memory_x(unsigned long addr, int numpages)
{
return change_memory_common(addr, numpages,
- __pgprot(0),
+ __pgprot(PTE_MAYBE_GP),
__pgprot(PTE_PXN));
}

--
2.20.1