diff options
Diffstat (limited to 'arch/powerpc/include/asm/kup.h')
| -rw-r--r-- | arch/powerpc/include/asm/kup.h | 171 |
1 files changed, 142 insertions, 29 deletions
diff --git a/arch/powerpc/include/asm/kup.h b/arch/powerpc/include/asm/kup.h index 5b5e39643a27..ad7e8c5aec3f 100644 --- a/arch/powerpc/include/asm/kup.h +++ b/arch/powerpc/include/asm/kup.h @@ -2,72 +2,185 @@ #ifndef _ASM_POWERPC_KUP_H_ #define _ASM_POWERPC_KUP_H_ -#ifdef CONFIG_PPC64 -#include <asm/book3s/64/kup-radix.h> +#define KUAP_READ 1 +#define KUAP_WRITE 2 +#define KUAP_READ_WRITE (KUAP_READ | KUAP_WRITE) + +#ifndef __ASSEMBLY__ +#include <linux/types.h> + +static __always_inline bool kuap_is_disabled(void); +#endif + +#ifdef CONFIG_PPC_BOOK3S_64 +#include <asm/book3s/64/kup.h> #endif + #ifdef CONFIG_PPC_8xx #include <asm/nohash/32/kup-8xx.h> #endif + +#ifdef CONFIG_BOOKE_OR_40x +#include <asm/nohash/kup-booke.h> +#endif + #ifdef CONFIG_PPC_BOOK3S_32 #include <asm/book3s/32/kup.h> #endif #ifdef __ASSEMBLY__ #ifndef CONFIG_PPC_KUAP -.macro kuap_save_and_lock sp, thread, gpr1, gpr2, gpr3 -.endm - -.macro kuap_restore sp, current, gpr1, gpr2, gpr3 -.endm - -.macro kuap_check current, gpr +.macro kuap_check_amr gpr1, gpr2 .endm #endif #else /* !__ASSEMBLY__ */ -#include <asm/pgtable.h> +extern bool disable_kuep; +extern bool disable_kuap; -void setup_kup(void); +#include <linux/pgtable.h> -#ifdef CONFIG_PPC_KUEP +void setup_kup(void); void setup_kuep(bool disabled); -#else -static inline void setup_kuep(bool disabled) { } -#endif /* CONFIG_PPC_KUEP */ #ifdef CONFIG_PPC_KUAP void setup_kuap(bool disabled); + +static __always_inline bool kuap_is_disabled(void) +{ + return !mmu_has_feature(MMU_FTR_KUAP); +} #else static inline void setup_kuap(bool disabled) { } -static inline void allow_user_access(void __user *to, const void __user *from, - unsigned long size) { } -static inline void prevent_user_access(void __user *to, const void __user *from, - unsigned long size) { } -static inline bool bad_kuap_fault(struct pt_regs *regs, bool is_write) { return false; } + +static __always_inline bool kuap_is_disabled(void) { return true; } + +static __always_inline bool +__bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write) +{ + return false; +} + +static __always_inline void kuap_user_restore(struct pt_regs *regs) { } +static __always_inline void __kuap_kernel_restore(struct pt_regs *regs, unsigned long amr) { } + +/* + * book3s/64/kup-radix.h defines these functions for the !KUAP case to flush + * the L1D cache after user accesses. Only include the empty stubs for other + * platforms. + */ +#ifndef CONFIG_PPC_BOOK3S_64 +static __always_inline void allow_user_access(void __user *to, const void __user *from, + unsigned long size, unsigned long dir) { } +static __always_inline void prevent_user_access(unsigned long dir) { } +static __always_inline unsigned long prevent_user_access_return(void) { return 0UL; } +static __always_inline void restore_user_access(unsigned long flags) { } +#endif /* CONFIG_PPC_BOOK3S_64 */ #endif /* CONFIG_PPC_KUAP */ -static inline void allow_read_from_user(const void __user *from, unsigned long size) +static __always_inline bool +bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write) +{ + if (kuap_is_disabled()) + return false; + + return __bad_kuap_fault(regs, address, is_write); +} + +static __always_inline void kuap_lock(void) +{ +#ifdef __kuap_lock + if (kuap_is_disabled()) + return; + + __kuap_lock(); +#endif +} + +static __always_inline void kuap_save_and_lock(struct pt_regs *regs) +{ +#ifdef __kuap_save_and_lock + if (kuap_is_disabled()) + return; + + __kuap_save_and_lock(regs); +#endif +} + +static __always_inline void kuap_kernel_restore(struct pt_regs *regs, unsigned long amr) +{ + if (kuap_is_disabled()) + return; + + __kuap_kernel_restore(regs, amr); +} + +static __always_inline unsigned long kuap_get_and_assert_locked(void) +{ +#ifdef __kuap_get_and_assert_locked + if (!kuap_is_disabled()) + return __kuap_get_and_assert_locked(); +#endif + return 0; +} + +static __always_inline void kuap_assert_locked(void) +{ + if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG)) + kuap_get_and_assert_locked(); +} + +static __always_inline void allow_read_from_user(const void __user *from, unsigned long size) +{ + barrier_nospec(); + allow_user_access(NULL, from, size, KUAP_READ); +} + +static __always_inline void allow_write_to_user(void __user *to, unsigned long size) +{ + allow_user_access(to, NULL, size, KUAP_WRITE); +} + +static __always_inline void allow_read_write_user(void __user *to, const void __user *from, + unsigned long size) +{ + barrier_nospec(); + allow_user_access(to, from, size, KUAP_READ_WRITE); +} + +static __always_inline void prevent_read_from_user(const void __user *from, unsigned long size) +{ + prevent_user_access(KUAP_READ); +} + +static __always_inline void prevent_write_to_user(void __user *to, unsigned long size) +{ + prevent_user_access(KUAP_WRITE); +} + +static __always_inline void prevent_read_write_user(void __user *to, const void __user *from, + unsigned long size) { - allow_user_access(NULL, from, size); + prevent_user_access(KUAP_READ_WRITE); } -static inline void allow_write_to_user(void __user *to, unsigned long size) +static __always_inline void prevent_current_access_user(void) { - allow_user_access(to, NULL, size); + prevent_user_access(KUAP_READ_WRITE); } -static inline void prevent_read_from_user(const void __user *from, unsigned long size) +static __always_inline void prevent_current_read_from_user(void) { - prevent_user_access(NULL, from, size); + prevent_user_access(KUAP_READ); } -static inline void prevent_write_to_user(void __user *to, unsigned long size) +static __always_inline void prevent_current_write_to_user(void) { - prevent_user_access(to, NULL, size); + prevent_user_access(KUAP_WRITE); } #endif /* !__ASSEMBLY__ */ -#endif /* _ASM_POWERPC_KUP_H_ */ +#endif /* _ASM_POWERPC_KUAP_H_ */ |