diff options
| -rw-r--r-- | arch/powerpc/include/asm/kup.h | 3 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/nohash/32/kup-8xx.h | 58 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/nohash/32/mmu-8xx.h | 7 | ||||
| -rw-r--r-- | arch/powerpc/mm/8xx_mmu.c | 12 | ||||
| -rw-r--r-- | arch/powerpc/platforms/Kconfig.cputype | 1 |
5 files changed, 81 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/kup.h b/arch/powerpc/include/asm/kup.h index 7d8ad3d6729d..043c800ec5fb 100644 --- a/arch/powerpc/include/asm/kup.h +++ b/arch/powerpc/include/asm/kup.h @@ -5,6 +5,9 @@ #ifdef CONFIG_PPC64 #include <asm/book3s/64/kup-radix.h> #endif +#ifdef CONFIG_PPC_8xx +#include <asm/nohash/32/kup-8xx.h> +#endif #ifdef __ASSEMBLY__ #ifndef CONFIG_PPC_KUAP diff --git a/arch/powerpc/include/asm/nohash/32/kup-8xx.h b/arch/powerpc/include/asm/nohash/32/kup-8xx.h new file mode 100644 index 000000000000..1c3133b5f86a --- /dev/null +++ b/arch/powerpc/include/asm/nohash/32/kup-8xx.h @@ -0,0 +1,58 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_POWERPC_KUP_8XX_H_ +#define _ASM_POWERPC_KUP_8XX_H_ + +#include <asm/bug.h> + +#ifdef CONFIG_PPC_KUAP + +#ifdef __ASSEMBLY__ + +.macro kuap_save_and_lock sp, thread, gpr1, gpr2, gpr3 + lis \gpr2, MD_APG_KUAP@h /* only APG0 and APG1 are used */ + mfspr \gpr1, SPRN_MD_AP + mtspr SPRN_MD_AP, \gpr2 + stw \gpr1, STACK_REGS_KUAP(\sp) +.endm + +.macro kuap_restore sp, current, gpr1, gpr2, gpr3 + lwz \gpr1, STACK_REGS_KUAP(\sp) + mtspr SPRN_MD_AP, \gpr1 +.endm + +.macro kuap_check current, gpr +#ifdef CONFIG_PPC_KUAP_DEBUG + mfspr \gpr, SPRN_MD_AP + rlwinm \gpr, \gpr, 16, 0xffff +999: twnei \gpr, MD_APG_KUAP@h + EMIT_BUG_ENTRY 999b, __FILE__, __LINE__, (BUGFLAG_WARNING | BUGFLAG_ONCE) +#endif +.endm + +#else /* !__ASSEMBLY__ */ + +#include <asm/reg.h> + +static inline void allow_user_access(void __user *to, const void __user *from, + unsigned long size) +{ + mtspr(SPRN_MD_AP, MD_APG_INIT); +} + +static inline void prevent_user_access(void __user *to, const void __user *from, + unsigned long size) +{ + mtspr(SPRN_MD_AP, MD_APG_KUAP); +} + +static inline bool bad_kuap_fault(struct pt_regs *regs, bool is_write) +{ + return WARN(!((regs->kuap ^ MD_APG_KUAP) & 0xf0000000), + "Bug: fault blocked by AP register !"); +} + +#endif /* !__ASSEMBLY__ */ + +#endif /* CONFIG_PPC_KUAP */ + +#endif /* _ASM_POWERPC_KUP_8XX_H_ */ diff --git a/arch/powerpc/include/asm/nohash/32/mmu-8xx.h b/arch/powerpc/include/asm/nohash/32/mmu-8xx.h index 3cb743284e09..f620adef54fc 100644 --- a/arch/powerpc/include/asm/nohash/32/mmu-8xx.h +++ b/arch/powerpc/include/asm/nohash/32/mmu-8xx.h @@ -121,6 +121,13 @@ */ #define MD_APG_INIT 0x4fffffff +/* + * 0 => No user => 01 (all accesses performed according to page definition) + * 1 => User => 10 (all accesses performed according to swaped page definition) + * 2-16 => NA => 11 (all accesses performed as user iaw page definition) + */ +#define MD_APG_KUAP 0x6fffffff + /* The effective page number register. When read, contains the information * about the last instruction TLB miss. When MD_RPN is written, bits in * this register are used to create the TLB entry. diff --git a/arch/powerpc/mm/8xx_mmu.c b/arch/powerpc/mm/8xx_mmu.c index e257a0c9bd08..87648b58d295 100644 --- a/arch/powerpc/mm/8xx_mmu.c +++ b/arch/powerpc/mm/8xx_mmu.c @@ -225,3 +225,15 @@ void __init setup_kuep(bool disabled) mtspr(SPRN_MI_AP, MI_APG_KUEP); } #endif + +#ifdef CONFIG_PPC_KUAP +void __init setup_kuap(bool disabled) +{ + pr_info("Activating Kernel Userspace Access Protection\n"); + + if (disabled) + pr_warn("KUAP cannot be disabled yet on 8xx when compiled in\n"); + + mtspr(SPRN_MD_AP, MD_APG_KUAP); +} +#endif diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype index 00fa0d110dcb..ab586963893a 100644 --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -35,6 +35,7 @@ config PPC_8xx select FSL_SOC select SYS_SUPPORTS_HUGETLBFS select PPC_HAVE_KUEP + select PPC_HAVE_KUAP config 40x bool "AMCC 40x" |