diff options
| -rw-r--r-- | arch/arm64/include/asm/pointer_auth.h | 12 | ||||
| -rw-r--r-- | arch/arm64/include/asm/processor.h | 2 | ||||
| -rw-r--r-- | arch/arm64/kernel/mte.c | 8 | ||||
| -rw-r--r-- | arch/arm64/kernel/pointer_auth.c | 10 | ||||
| -rw-r--r-- | arch/arm64/kernel/process.c | 21 |
5 files changed, 24 insertions, 29 deletions
diff --git a/arch/arm64/include/asm/pointer_auth.h b/arch/arm64/include/asm/pointer_auth.h index 28a78b67d9b4..efb098de3a84 100644 --- a/arch/arm64/include/asm/pointer_auth.h +++ b/arch/arm64/include/asm/pointer_auth.h @@ -10,6 +10,9 @@ #include <asm/memory.h> #include <asm/sysreg.h> +#define PR_PAC_ENABLED_KEYS_MASK \ + (PR_PAC_APIAKEY | PR_PAC_APIBKEY | PR_PAC_APDAKEY | PR_PAC_APDBKEY) + #ifdef CONFIG_ARM64_PTR_AUTH /* * Each key is a 128-bit quantity which is split across a pair of 64-bit @@ -117,9 +120,9 @@ static __always_inline void ptrauth_enable(void) \ /* enable all keys */ \ if (system_supports_address_auth()) \ - set_task_sctlr_el1(current->thread.sctlr_user | \ - SCTLR_ELx_ENIA | SCTLR_ELx_ENIB | \ - SCTLR_ELx_ENDA | SCTLR_ELx_ENDB); \ + ptrauth_set_enabled_keys(current, \ + PR_PAC_ENABLED_KEYS_MASK, \ + PR_PAC_ENABLED_KEYS_MASK); \ } while (0) #define ptrauth_thread_switch_user(tsk) \ @@ -146,7 +149,4 @@ static __always_inline void ptrauth_enable(void) #define ptrauth_thread_switch_kernel(tsk) #endif /* CONFIG_ARM64_PTR_AUTH_KERNEL */ -#define PR_PAC_ENABLED_KEYS_MASK \ - (PR_PAC_APIAKEY | PR_PAC_APIBKEY | PR_PAC_APDAKEY | PR_PAC_APDBKEY) - #endif /* __ASM_POINTER_AUTH_H */ diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index ee82ebbb5e5a..ee2bdc1b9f5b 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -259,7 +259,7 @@ extern void release_thread(struct task_struct *); unsigned long get_wchan(struct task_struct *p); -void set_task_sctlr_el1(u64 sctlr); +void update_sctlr_el1(u64 sctlr); /* Thread switching */ extern struct task_struct *cpu_switch_to(struct task_struct *prev, diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c index 3b6b68518003..737503a148bb 100644 --- a/arch/arm64/kernel/mte.c +++ b/arch/arm64/kernel/mte.c @@ -218,9 +218,7 @@ void mte_thread_init_user(void) write_sysreg_s(0, SYS_TFSRE0_EL1); clear_thread_flag(TIF_MTE_ASYNC_FAULT); /* disable tag checking and reset tag generation mask */ - current->thread.mte_ctrl = MTE_CTRL_GCR_USER_EXCL_MASK; - mte_update_sctlr_user(current); - set_task_sctlr_el1(current->thread.sctlr_user); + set_mte_ctrl(current, 0); } void mte_thread_switch(struct task_struct *next) @@ -278,8 +276,10 @@ long set_mte_ctrl(struct task_struct *task, unsigned long arg) task->thread.mte_ctrl = mte_ctrl; if (task == current) { + preempt_disable(); mte_update_sctlr_user(task); - set_task_sctlr_el1(task->thread.sctlr_user); + update_sctlr_el1(task->thread.sctlr_user); + preempt_enable(); } return 0; diff --git a/arch/arm64/kernel/pointer_auth.c b/arch/arm64/kernel/pointer_auth.c index 60901ab0a7fe..2708b620b4ae 100644 --- a/arch/arm64/kernel/pointer_auth.c +++ b/arch/arm64/kernel/pointer_auth.c @@ -67,7 +67,7 @@ static u64 arg_to_enxx_mask(unsigned long arg) int ptrauth_set_enabled_keys(struct task_struct *tsk, unsigned long keys, unsigned long enabled) { - u64 sctlr = tsk->thread.sctlr_user; + u64 sctlr; if (!system_supports_address_auth()) return -EINVAL; @@ -78,12 +78,14 @@ int ptrauth_set_enabled_keys(struct task_struct *tsk, unsigned long keys, if ((keys & ~PR_PAC_ENABLED_KEYS_MASK) || (enabled & ~keys)) return -EINVAL; + preempt_disable(); + sctlr = tsk->thread.sctlr_user; sctlr &= ~arg_to_enxx_mask(keys); sctlr |= arg_to_enxx_mask(enabled); + tsk->thread.sctlr_user = sctlr; if (tsk == current) - set_task_sctlr_el1(sctlr); - else - tsk->thread.sctlr_user = sctlr; + update_sctlr_el1(sctlr); + preempt_enable(); return 0; } diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index c8989b999250..8811c303608b 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -477,7 +477,13 @@ static void compat_thread_switch(struct task_struct *next) set_tsk_thread_flag(next, TIF_NOTIFY_RESUME); } -static void update_sctlr_el1(u64 sctlr) +/* + * __switch_to() checks current->thread.sctlr_user as an optimisation. Therefore + * this function must be called with preemption disabled and the update to + * sctlr_user must be made in the same preemption disabled block so that + * __switch_to() does not see the variable update before the SCTLR_EL1 one. + */ +void update_sctlr_el1(u64 sctlr) { /* * EnIA must not be cleared while in the kernel as this is necessary for @@ -489,19 +495,6 @@ static void update_sctlr_el1(u64 sctlr) isb(); } -void set_task_sctlr_el1(u64 sctlr) -{ - /* - * __switch_to() checks current->thread.sctlr as an - * optimisation. Disable preemption so that it does not see - * the variable update before the SCTLR_EL1 one. - */ - preempt_disable(); - current->thread.sctlr_user = sctlr; - update_sctlr_el1(sctlr); - preempt_enable(); -} - /* * Thread switching. */ |