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Diffstat (limited to 'arch/powerpc/include/asm/kup.h')
| -rw-r--r-- | arch/powerpc/include/asm/kup.h | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/kup.h b/arch/powerpc/include/asm/kup.h new file mode 100644 index 000000000..d751ddd08 --- /dev/null +++ b/arch/powerpc/include/asm/kup.h @@ -0,0 +1,215 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_POWERPC_KUP_H_ +#define _ASM_POWERPC_KUP_H_ + +#define KUAP_READ 1 +#define KUAP_WRITE 2 +#define KUAP_READ_WRITE (KUAP_READ | KUAP_WRITE) + +#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_check_amr gpr1, gpr2 +.endm + +#endif + +#else /* !__ASSEMBLY__ */ + +extern bool disable_kuep; +extern bool disable_kuap; + +#include <linux/pgtable.h> + +void setup_kup(void); +void setup_kuep(bool disabled); + +#ifdef CONFIG_PPC_KUAP +void setup_kuap(bool disabled); +#else +static inline void setup_kuap(bool disabled) { } + +static __always_inline bool kuap_is_disabled(void) { return true; } + +static inline bool +__bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write) +{ + return false; +} + +static inline void __kuap_lock(void) { } +static inline void __kuap_save_and_lock(struct pt_regs *regs) { } +static inline void kuap_user_restore(struct pt_regs *regs) { } +static inline void __kuap_kernel_restore(struct pt_regs *regs, unsigned long amr) { } + +static inline unsigned long __kuap_get_and_assert_locked(void) +{ + return 0; +} + +/* + * 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 inline void __allow_user_access(void __user *to, const void __user *from, + unsigned long size, unsigned long dir) { } +static inline void __prevent_user_access(unsigned long dir) { } +static inline unsigned long __prevent_user_access_return(void) { return 0UL; } +static inline void __restore_user_access(unsigned long flags) { } +#endif /* CONFIG_PPC_BOOK3S_64 */ +#endif /* CONFIG_PPC_KUAP */ + +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_assert_locked(void) +{ + if (kuap_is_disabled()) + return; + + if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG)) + __kuap_get_and_assert_locked(); +} + +static __always_inline void kuap_lock(void) +{ + if (kuap_is_disabled()) + return; + + __kuap_lock(); +} + +static __always_inline void kuap_save_and_lock(struct pt_regs *regs) +{ + if (kuap_is_disabled()) + return; + + __kuap_save_and_lock(regs); +} + +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) +{ + if (kuap_is_disabled()) + return 0; + + return __kuap_get_and_assert_locked(); +} + +#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) +{ + if (kuap_is_disabled()) + return; + + __allow_user_access(to, from, size, dir); +} + +static __always_inline void prevent_user_access(unsigned long dir) +{ + if (kuap_is_disabled()) + return; + + __prevent_user_access(dir); +} + +static __always_inline unsigned long prevent_user_access_return(void) +{ + if (kuap_is_disabled()) + return 0; + + return __prevent_user_access_return(); +} + +static __always_inline void restore_user_access(unsigned long flags) +{ + if (kuap_is_disabled()) + return; + + __restore_user_access(flags); +} +#endif /* CONFIG_PPC_BOOK3S_64 */ + +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) +{ + prevent_user_access(KUAP_READ_WRITE); +} + +static __always_inline void prevent_current_access_user(void) +{ + prevent_user_access(KUAP_READ_WRITE); +} + +static __always_inline void prevent_current_read_from_user(void) +{ + prevent_user_access(KUAP_READ); +} + +static __always_inline void prevent_current_write_to_user(void) +{ + prevent_user_access(KUAP_WRITE); +} + +#endif /* !__ASSEMBLY__ */ + +#endif /* _ASM_POWERPC_KUAP_H_ */ |