diff options
Diffstat (limited to 'arch/arm64/include/asm/uaccess.h')
| -rw-r--r-- | arch/arm64/include/asm/uaccess.h | 78 |
1 files changed, 48 insertions, 30 deletions
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index 190b494e22ab..3a5ff5e20586 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -18,6 +18,7 @@ #include <linux/kasan-checks.h> #include <linux/string.h> +#include <asm/asm-extable.h> #include <asm/cpufeature.h> #include <asm/mmu.h> #include <asm/mte.h> @@ -70,12 +71,6 @@ static inline unsigned long __range_ok(const void __user *addr, unsigned long si #define access_ok(addr, size) __range_ok(addr, size) -#define _ASM_EXTABLE(from, to) \ - " .pushsection __ex_table, \"a\"\n" \ - " .align 3\n" \ - " .long (" #from " - .), (" #to " - .)\n" \ - " .popsection\n" - /* * User access enabling/disabling. */ @@ -196,13 +191,13 @@ static inline void __uaccess_enable_tco(void) */ static inline void __uaccess_disable_tco_async(void) { - if (system_uses_mte_async_mode()) + if (system_uses_mte_async_or_asymm_mode()) __uaccess_disable_tco(); } static inline void __uaccess_enable_tco_async(void) { - if (system_uses_mte_async_mode()) + if (system_uses_mte_async_or_asymm_mode()) __uaccess_enable_tco(); } @@ -260,15 +255,9 @@ static inline void __user *__uaccess_mask_ptr(const void __user *ptr) asm volatile( \ "1: " load " " reg "1, [%2]\n" \ "2:\n" \ - " .section .fixup, \"ax\"\n" \ - " .align 2\n" \ - "3: mov %w0, %3\n" \ - " mov %1, #0\n" \ - " b 2b\n" \ - " .previous\n" \ - _ASM_EXTABLE(1b, 3b) \ + _ASM_EXTABLE_UACCESS_ERR_ZERO(1b, 2b, %w0, %w1) \ : "+r" (err), "=&r" (x) \ - : "r" (addr), "i" (-EFAULT)) + : "r" (addr)) #define __raw_get_mem(ldr, x, ptr, err) \ do { \ @@ -292,12 +281,22 @@ do { \ (x) = (__force __typeof__(*(ptr)))__gu_val; \ } while (0) +/* + * We must not call into the scheduler between uaccess_ttbr0_enable() and + * uaccess_ttbr0_disable(). As `x` and `ptr` could contain blocking functions, + * we must evaluate these outside of the critical section. + */ #define __raw_get_user(x, ptr, err) \ do { \ + __typeof__(*(ptr)) __user *__rgu_ptr = (ptr); \ + __typeof__(x) __rgu_val; \ __chk_user_ptr(ptr); \ + \ uaccess_ttbr0_enable(); \ - __raw_get_mem("ldtr", x, ptr, err); \ + __raw_get_mem("ldtr", __rgu_val, __rgu_ptr, err); \ uaccess_ttbr0_disable(); \ + \ + (x) = __rgu_val; \ } while (0) #define __get_user_error(x, ptr, err) \ @@ -321,14 +320,22 @@ do { \ #define get_user __get_user +/* + * We must not call into the scheduler between __uaccess_enable_tco_async() and + * __uaccess_disable_tco_async(). As `dst` and `src` may contain blocking + * functions, we must evaluate these outside of the critical section. + */ #define __get_kernel_nofault(dst, src, type, err_label) \ do { \ + __typeof__(dst) __gkn_dst = (dst); \ + __typeof__(src) __gkn_src = (src); \ int __gkn_err = 0; \ \ __uaccess_enable_tco_async(); \ - __raw_get_mem("ldr", *((type *)(dst)), \ - (__force type *)(src), __gkn_err); \ + __raw_get_mem("ldr", *((type *)(__gkn_dst)), \ + (__force type *)(__gkn_src), __gkn_err); \ __uaccess_disable_tco_async(); \ + \ if (unlikely(__gkn_err)) \ goto err_label; \ } while (0) @@ -337,14 +344,9 @@ do { \ asm volatile( \ "1: " store " " reg "1, [%2]\n" \ "2:\n" \ - " .section .fixup,\"ax\"\n" \ - " .align 2\n" \ - "3: mov %w0, %3\n" \ - " b 2b\n" \ - " .previous\n" \ - _ASM_EXTABLE(1b, 3b) \ + _ASM_EXTABLE_UACCESS_ERR(1b, 2b, %w0) \ : "+r" (err) \ - : "r" (x), "r" (addr), "i" (-EFAULT)) + : "r" (x), "r" (addr)) #define __raw_put_mem(str, x, ptr, err) \ do { \ @@ -367,11 +369,19 @@ do { \ } \ } while (0) +/* + * We must not call into the scheduler between uaccess_ttbr0_enable() and + * uaccess_ttbr0_disable(). As `x` and `ptr` could contain blocking functions, + * we must evaluate these outside of the critical section. + */ #define __raw_put_user(x, ptr, err) \ do { \ - __chk_user_ptr(ptr); \ + __typeof__(*(ptr)) __user *__rpu_ptr = (ptr); \ + __typeof__(*(ptr)) __rpu_val = (x); \ + __chk_user_ptr(__rpu_ptr); \ + \ uaccess_ttbr0_enable(); \ - __raw_put_mem("sttr", x, ptr, err); \ + __raw_put_mem("sttr", __rpu_val, __rpu_ptr, err); \ uaccess_ttbr0_disable(); \ } while (0) @@ -396,14 +406,22 @@ do { \ #define put_user __put_user +/* + * We must not call into the scheduler between __uaccess_enable_tco_async() and + * __uaccess_disable_tco_async(). As `dst` and `src` may contain blocking + * functions, we must evaluate these outside of the critical section. + */ #define __put_kernel_nofault(dst, src, type, err_label) \ do { \ + __typeof__(dst) __pkn_dst = (dst); \ + __typeof__(src) __pkn_src = (src); \ int __pkn_err = 0; \ \ __uaccess_enable_tco_async(); \ - __raw_put_mem("str", *((type *)(src)), \ - (__force type *)(dst), __pkn_err); \ + __raw_put_mem("str", *((type *)(__pkn_src)), \ + (__force type *)(__pkn_dst), __pkn_err); \ __uaccess_disable_tco_async(); \ + \ if (unlikely(__pkn_err)) \ goto err_label; \ } while(0) |