[PATCH RFC v9 19/25] arm64: kpkeys: Protect early page tables
Kevin Brodsky <[email protected]>
| Newsgroups | org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-hardening,org.kvack.linux-mm |
|---|---|
| Message-ID | <[email protected]> |
Use the dedicated kpkeys allocator for early page tables (used to create the linear map) when the kpkeys_hardened_pgtables feature is enabled. CPU features have not been detected at this stage so we use the early_enabled() helper. This is not a concern as kpkeys_physmem_pgtable_alloc() does not itself use POE or set_memory_pkey(). Signed-off-by: Kevin Brodsky <[email protected]> --- arch/arm64/mm/mmu.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 0d7e41d17182..a10e9f9876d0 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -107,8 +107,11 @@ static phys_addr_t __init early_pgtable_alloc(enum pgtable_level pgtable_level) { phys_addr_t phys; - phys = memblock_phys_alloc_range(PAGE_SIZE, PAGE_SIZE, 0, - MEMBLOCK_ALLOC_NOLEAKTRACE); + if (kpkeys_hardened_pgtables_early_enabled()) + phys = kpkeys_physmem_pgtable_alloc(); + else + phys = memblock_phys_alloc_range(PAGE_SIZE, PAGE_SIZE, 0, + MEMBLOCK_ALLOC_NOLEAKTRACE); if (!phys) panic("Failed to allocate page table page\n"); -- 2.51.2