diff options
Diffstat (limited to 'arch/powerpc/mm/book3s32/kuep.c')
| -rw-r--r-- | arch/powerpc/mm/book3s32/kuep.c | 42 |
1 files changed, 11 insertions, 31 deletions
diff --git a/arch/powerpc/mm/book3s32/kuep.c b/arch/powerpc/mm/book3s32/kuep.c index 8ed1b8634839..c20733d6e02c 100644 --- a/arch/powerpc/mm/book3s32/kuep.c +++ b/arch/powerpc/mm/book3s32/kuep.c @@ -1,40 +1,20 @@ // SPDX-License-Identifier: GPL-2.0-or-later #include <asm/kup.h> -#include <asm/reg.h> -#include <asm/task_size_32.h> -#include <asm/mmu.h> +#include <asm/smp.h> -#define KUEP_UPDATE_TWO_USER_SEGMENTS(n) do { \ - if (TASK_SIZE > ((n) << 28)) \ - mtsr(val1, (n) << 28); \ - if (TASK_SIZE > (((n) + 1) << 28)) \ - mtsr(val2, ((n) + 1) << 28); \ - val1 = (val1 + 0x222) & 0xf0ffffff; \ - val2 = (val2 + 0x222) & 0xf0ffffff; \ -} while (0) +struct static_key_false disable_kuep_key; -static __always_inline void kuep_update(u32 val) +void setup_kuep(bool disabled) { - int val1 = val; - int val2 = (val + 0x111) & 0xf0ffffff; + if (!disabled) + kuep_lock(); - KUEP_UPDATE_TWO_USER_SEGMENTS(0); - KUEP_UPDATE_TWO_USER_SEGMENTS(2); - KUEP_UPDATE_TWO_USER_SEGMENTS(4); - KUEP_UPDATE_TWO_USER_SEGMENTS(6); - KUEP_UPDATE_TWO_USER_SEGMENTS(8); - KUEP_UPDATE_TWO_USER_SEGMENTS(10); - KUEP_UPDATE_TWO_USER_SEGMENTS(12); - KUEP_UPDATE_TWO_USER_SEGMENTS(14); -} + if (smp_processor_id() != boot_cpuid) + return; -void kuep_lock(void) -{ - kuep_update(mfsr(0) | SR_NX); -} - -void kuep_unlock(void) -{ - kuep_update(mfsr(0) & ~SR_NX); + if (disabled) + static_branch_enable(&disable_kuep_key); + else + pr_info("Activating Kernel Userspace Execution Prevention\n"); } |