diff options
Diffstat (limited to 'arch/arm64/include/asm/uaccess.h')
| -rw-r--r-- | arch/arm64/include/asm/uaccess.h | 108 |
1 files changed, 58 insertions, 50 deletions
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index c37c064d7cdd..efafdf39cb3b 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -18,6 +18,10 @@ #ifndef __ASM_UACCESS_H #define __ASM_UACCESS_H +#include <asm/alternative.h> +#include <asm/kernel-pgtable.h> +#include <asm/sysreg.h> + #ifndef __ASSEMBLY__ /* @@ -26,11 +30,8 @@ #include <linux/string.h> #include <linux/thread_info.h> -#include <asm/alternative.h> #include <asm/cpufeature.h> -#include <asm/kernel-pgtable.h> #include <asm/ptrace.h> -#include <asm/sysreg.h> #include <asm/errno.h> #include <asm/memory.h> #include <asm/compiler.h> @@ -130,7 +131,7 @@ static inline void set_fs(mm_segment_t fs) * User access enabling/disabling. */ #ifdef CONFIG_ARM64_SW_TTBR0_PAN -static inline void uaccess_ttbr0_disable(void) +static inline void __uaccess_ttbr0_disable(void) { unsigned long ttbr; @@ -140,7 +141,7 @@ static inline void uaccess_ttbr0_disable(void) isb(); } -static inline void uaccess_ttbr0_enable(void) +static inline void __uaccess_ttbr0_enable(void) { unsigned long flags; @@ -154,30 +155,44 @@ static inline void uaccess_ttbr0_enable(void) isb(); local_irq_restore(flags); } + +static inline bool uaccess_ttbr0_disable(void) +{ + if (!system_uses_ttbr0_pan()) + return false; + __uaccess_ttbr0_disable(); + return true; +} + +static inline bool uaccess_ttbr0_enable(void) +{ + if (!system_uses_ttbr0_pan()) + return false; + __uaccess_ttbr0_enable(); + return true; +} #else -static inline void uaccess_ttbr0_disable(void) +static inline bool uaccess_ttbr0_disable(void) { + return false; } -static inline void uaccess_ttbr0_enable(void) +static inline bool uaccess_ttbr0_enable(void) { + return false; } #endif #define __uaccess_disable(alt) \ do { \ - if (system_uses_ttbr0_pan()) \ - uaccess_ttbr0_disable(); \ - else \ + if (!uaccess_ttbr0_disable()) \ asm(ALTERNATIVE("nop", SET_PSTATE_PAN(1), alt, \ CONFIG_ARM64_PAN)); \ } while (0) #define __uaccess_enable(alt) \ do { \ - if (system_uses_ttbr0_pan()) \ - uaccess_ttbr0_enable(); \ - else \ + if (!uaccess_ttbr0_enable()) \ asm(ALTERNATIVE("nop", SET_PSTATE_PAN(0), alt, \ CONFIG_ARM64_PAN)); \ } while (0) @@ -407,69 +422,62 @@ extern __must_check long strnlen_user(const char __user *str, long n); #else /* __ASSEMBLY__ */ -#include <asm/alternative.h> #include <asm/assembler.h> -#include <asm/kernel-pgtable.h> /* * User access enabling/disabling macros. */ - .macro uaccess_ttbr0_disable, tmp1 +#ifdef CONFIG_ARM64_SW_TTBR0_PAN + .macro __uaccess_ttbr0_disable, tmp1 mrs \tmp1, ttbr1_el1 // swapper_pg_dir add \tmp1, \tmp1, #SWAPPER_DIR_SIZE // reserved_ttbr0 at the end of swapper_pg_dir msr ttbr0_el1, \tmp1 // set reserved TTBR0_EL1 isb .endm - .macro uaccess_ttbr0_enable, tmp1 + .macro __uaccess_ttbr0_enable, tmp1 get_thread_info \tmp1 - ldr \tmp1, [\tmp1, #TI_TTBR0] // load saved TTBR0_EL1 + ldr \tmp1, [\tmp1, #TSK_TI_TTBR0] // load saved TTBR0_EL1 msr ttbr0_el1, \tmp1 // set the non-PAN TTBR0_EL1 isb .endm + .macro uaccess_ttbr0_disable, tmp1 +alternative_if_not ARM64_HAS_PAN + __uaccess_ttbr0_disable \tmp1 +alternative_else_nop_endif + .endm + + .macro uaccess_ttbr0_enable, tmp1, tmp2 +alternative_if_not ARM64_HAS_PAN + save_and_disable_irq \tmp2 // avoid preemption + __uaccess_ttbr0_enable \tmp1 + restore_irq \tmp2 +alternative_else_nop_endif + .endm +#else + .macro uaccess_ttbr0_disable, tmp1 + .endm + + .macro uaccess_ttbr0_enable, tmp1, tmp2 + .endm +#endif + /* * These macros are no-ops when UAO is present. */ .macro uaccess_disable_not_uao, tmp1 -#ifdef CONFIG_ARM64_SW_TTBR0_PAN -alternative_if_not ARM64_HAS_PAN uaccess_ttbr0_disable \tmp1 -alternative_else - nop - nop - nop - nop -alternative_endif -#endif -alternative_if_not ARM64_ALT_PAN_NOT_UAO - nop -alternative_else +alternative_if ARM64_ALT_PAN_NOT_UAO SET_PSTATE_PAN(1) -alternative_endif +alternative_else_nop_endif .endm .macro uaccess_enable_not_uao, tmp1, tmp2 -#ifdef CONFIG_ARM64_SW_TTBR0_PAN -alternative_if_not ARM64_HAS_PAN - save_and_disable_irq \tmp2 // avoid preemption - uaccess_ttbr0_enable \tmp1 - restore_irq \tmp2 -alternative_else - nop - nop - nop - nop - nop - nop - nop -alternative_endif -#endif -alternative_if_not ARM64_ALT_PAN_NOT_UAO - nop -alternative_else + uaccess_ttbr0_enable \tmp1, \tmp2 +alternative_if ARM64_ALT_PAN_NOT_UAO SET_PSTATE_PAN(0) -alternative_endif +alternative_else_nop_endif .endm #endif /* __ASSEMBLY__ */ |