diff options
Diffstat (limited to 'arch/powerpc/include/asm/book3s/32/kup.h')
-rw-r--r-- | arch/powerpc/include/asm/book3s/32/kup.h | 108 |
1 files changed, 24 insertions, 84 deletions
diff --git a/arch/powerpc/include/asm/book3s/32/kup.h b/arch/powerpc/include/asm/book3s/32/kup.h index 9f38040f0641..678f9c9d89b6 100644 --- a/arch/powerpc/include/asm/book3s/32/kup.h +++ b/arch/powerpc/include/asm/book3s/32/kup.h @@ -12,50 +12,10 @@ #include <linux/jump_label.h> extern struct static_key_false disable_kuap_key; -extern struct static_key_false disable_kuep_key; - -static __always_inline bool kuap_is_disabled(void) -{ - return !IS_ENABLED(CONFIG_PPC_KUAP) || static_branch_unlikely(&disable_kuap_key); -} static __always_inline bool kuep_is_disabled(void) { - return !IS_ENABLED(CONFIG_PPC_KUEP) || static_branch_unlikely(&disable_kuep_key); -} - -static inline void kuep_lock(void) -{ - if (kuep_is_disabled()) - return; - - update_user_segments(mfsr(0) | SR_NX); - /* - * This isync() shouldn't be necessary as the kernel is not excepted to - * run any instruction in userspace soon after the update of segments, - * but hash based cores (at least G3) seem to exhibit a random - * behaviour when the 'isync' is not there. 603 cores don't have this - * behaviour so don't do the 'isync' as it saves several CPU cycles. - */ - if (mmu_has_feature(MMU_FTR_HPTE_TABLE)) - isync(); /* Context sync required after mtsr() */ -} - -static inline void kuep_unlock(void) -{ - if (kuep_is_disabled()) - return; - - update_user_segments(mfsr(0) & ~SR_NX); - /* - * This isync() shouldn't be necessary as a 'rfi' will soon be executed - * to return to userspace, but hash based cores (at least G3) seem to - * exhibit a random behaviour when the 'isync' is not there. 603 cores - * don't have this behaviour so don't do the 'isync' as it saves several - * CPU cycles. - */ - if (mmu_has_feature(MMU_FTR_HPTE_TABLE)) - isync(); /* Context sync required after mtsr() */ + return !IS_ENABLED(CONFIG_PPC_KUEP); } #ifdef CONFIG_PPC_KUAP @@ -65,6 +25,11 @@ static inline void kuep_unlock(void) #define KUAP_NONE (~0UL) #define KUAP_ALL (~1UL) +static __always_inline bool kuap_is_disabled(void) +{ + return static_branch_unlikely(&disable_kuap_key); +} + static inline void kuap_lock_one(unsigned long addr) { mtsr(mfsr(addr) | SR_KS, addr); @@ -92,7 +57,7 @@ static inline void kuap_unlock_all(void) void kuap_lock_all_ool(void); void kuap_unlock_all_ool(void); -static inline void kuap_lock(unsigned long addr, bool ool) +static inline void kuap_lock_addr(unsigned long addr, bool ool) { if (likely(addr != KUAP_ALL)) kuap_lock_one(addr); @@ -112,33 +77,31 @@ static inline void kuap_unlock(unsigned long addr, bool ool) kuap_unlock_all_ool(); } -static inline void kuap_save_and_lock(struct pt_regs *regs) +static inline void __kuap_lock(void) { - unsigned long kuap = current->thread.kuap; +} - if (kuap_is_disabled()) - return; +static inline void __kuap_save_and_lock(struct pt_regs *regs) +{ + unsigned long kuap = current->thread.kuap; regs->kuap = kuap; if (unlikely(kuap == KUAP_NONE)) return; current->thread.kuap = KUAP_NONE; - kuap_lock(kuap, false); + kuap_lock_addr(kuap, false); } static inline void kuap_user_restore(struct pt_regs *regs) { } -static inline void kuap_kernel_restore(struct pt_regs *regs, unsigned long kuap) +static inline void __kuap_kernel_restore(struct pt_regs *regs, unsigned long kuap) { - if (kuap_is_disabled()) - return; - if (unlikely(kuap != KUAP_NONE)) { current->thread.kuap = KUAP_NONE; - kuap_lock(kuap, false); + kuap_lock_addr(kuap, false); } if (likely(regs->kuap == KUAP_NONE)) @@ -149,29 +112,18 @@ static inline void kuap_kernel_restore(struct pt_regs *regs, unsigned long kuap) kuap_unlock(regs->kuap, false); } -static inline unsigned long kuap_get_and_assert_locked(void) +static inline unsigned long __kuap_get_and_assert_locked(void) { unsigned long kuap = current->thread.kuap; - if (kuap_is_disabled()) - return KUAP_NONE; - WARN_ON_ONCE(IS_ENABLED(CONFIG_PPC_KUAP_DEBUG) && kuap != KUAP_NONE); return kuap; } -static inline void kuap_assert_locked(void) -{ - kuap_get_and_assert_locked(); -} - -static __always_inline void allow_user_access(void __user *to, const void __user *from, - u32 size, unsigned long dir) +static __always_inline void __allow_user_access(void __user *to, const void __user *from, + u32 size, unsigned long dir) { - if (kuap_is_disabled()) - return; - BUILD_BUG_ON(!__builtin_constant_p(dir)); if (!(dir & KUAP_WRITE)) @@ -181,42 +133,33 @@ static __always_inline void allow_user_access(void __user *to, const void __user kuap_unlock_one((__force u32)to); } -static __always_inline void prevent_user_access(unsigned long dir) +static __always_inline void __prevent_user_access(unsigned long dir) { u32 kuap = current->thread.kuap; - if (kuap_is_disabled()) - return; - BUILD_BUG_ON(!__builtin_constant_p(dir)); if (!(dir & KUAP_WRITE)) return; current->thread.kuap = KUAP_NONE; - kuap_lock(kuap, true); + kuap_lock_addr(kuap, true); } -static inline unsigned long prevent_user_access_return(void) +static inline unsigned long __prevent_user_access_return(void) { unsigned long flags = current->thread.kuap; - if (kuap_is_disabled()) - return KUAP_NONE; - if (flags != KUAP_NONE) { current->thread.kuap = KUAP_NONE; - kuap_lock(flags, true); + kuap_lock_addr(flags, true); } return flags; } -static inline void restore_user_access(unsigned long flags) +static inline void __restore_user_access(unsigned long flags) { - if (kuap_is_disabled()) - return; - if (flags != KUAP_NONE) { current->thread.kuap = flags; kuap_unlock(flags, true); @@ -224,13 +167,10 @@ static inline void restore_user_access(unsigned long flags) } static inline bool -bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write) +__bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write) { unsigned long kuap = regs->kuap; - if (kuap_is_disabled()) - return false; - if (!is_write || kuap == KUAP_ALL) return false; if (kuap == KUAP_NONE) |