On 12/08/2022 09:52, Tong Tiangen wrote:
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>
> Currently, The extable type EX_TYPE_UACCESS_ERR_ZERO is used by
> __get/put_kernel_nofault(), but those helpers are not uaccess type, so we
> add a new extable type EX_TYPE_KACCESS_ERR_ZERO which can be used by
> __get/put_kernel_no_fault().
>
> Also change the name of __get/put_user_nocheck to __get/put_mem_nocheck
> to make it conform to its use situation (not only used in uaccess).
Is there a reason why this should not be a different patch?
Thanks,
Conor.
>
> Signed-off-by: Tong Tiangen <tongtiangen at huawei.com>
> ---
> arch/riscv/include/asm/asm-extable.h | 12 ++
> arch/riscv/include/asm/uaccess.h | 160 +++++++++++++--------------
> 2 files changed, 92 insertions(+), 80 deletions(-)
>
> diff --git a/arch/riscv/include/asm/asm-extable.h b/arch/riscv/include/asm/asm-extable.h
> index 14be0673f5b5..73c70098a9c8 100644
> --- a/arch/riscv/include/asm/asm-extable.h
> +++ b/arch/riscv/include/asm/asm-extable.h
> @@ -6,6 +6,7 @@
> #define EX_TYPE_FIXUP 1
> #define EX_TYPE_BPF 2
> #define EX_TYPE_UACCESS_ERR_ZERO 3
> +#define EX_TYPE_KACCESS_ERR_ZERO 4
>
> #ifdef __ASSEMBLY__
>
> @@ -57,9 +58,20 @@
> EX_DATA_REG(ZERO, zero) \
> ")")
>
> +#define _ASM_EXTABLE_KACCESS_ERR_ZERO(insn, fixup, err, zero) \
> + __DEFINE_ASM_GPR_NUMS \
> + __ASM_EXTABLE_RAW(#insn, #fixup, \
> + __stringify(EX_TYPE_KACCESS_ERR_ZERO), \
> + "(" \
> + EX_DATA_REG(ERR, err) " | " \
> + EX_DATA_REG(ZERO, zero) \
> + ")")
> +
> #define _ASM_EXTABLE_UACCESS_ERR(insn, fixup, err) \
> _ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, zero)
>
> +#define _ASM_EXTABLE_KACCESS_ERR(insn, fixup, err) \
> + _ASM_EXTABLE_KACCESS_ERR_ZERO(insn, fixup, err, zero)
> #endif /* __ASSEMBLY__ */
>
> #endif /* __ASM_ASM_EXTABLE_H */
> diff --git a/arch/riscv/include/asm/uaccess.h b/arch/riscv/include/asm/uaccess.h
> index 855450bed9f5..5372f3f1e3f6 100644
> --- a/arch/riscv/include/asm/uaccess.h
> +++ b/arch/riscv/include/asm/uaccess.h
> @@ -50,62 +50,62 @@
> * call.
> */
>
> -#define __get_user_asm(insn, x, ptr, err) \
> -do { \
> - __typeof__(x) __x; \
> - __asm__ __volatile__ ( \
> - "1:\n" \
> - " " insn " %1, %2\n" \
> - "2:\n" \
> - _ASM_EXTABLE_UACCESS_ERR_ZERO(1b, 2b, %0, %1) \
> - : "+r" (err), "=&r" (__x) \
> - : "m" (*(ptr))); \
> - (x) = __x; \
> +#define __get_mem_asm(insn, x, ptr, err, type) \
> +do { \
> + __typeof__(x) __x; \
> + __asm__ __volatile__ ( \
> + "1:\n" \
> + " " insn " %1, %2\n" \
> + "2:\n" \
> + _ASM_EXTABLE_##type##ACCESS_ERR_ZERO(1b, 2b, %0, %1) \
> + : "+r" (err), "=&r" (__x) \
> + : "m" (*(ptr))); \
> + (x) = __x; \
> } while (0)
>
> #ifdef CONFIG_64BIT
> -#define __get_user_8(x, ptr, err) \
> - __get_user_asm("ld", x, ptr, err)
> +#define __get_mem_8(x, ptr, err, type) \
> + __get_mem_asm("ld", x, ptr, err, type)
> #else /* !CONFIG_64BIT */
> -#define __get_user_8(x, ptr, err) \
> -do { \
> - u32 __user *__ptr = (u32 __user *)(ptr); \
> - u32 __lo, __hi; \
> - __asm__ __volatile__ ( \
> - "1:\n" \
> - " lw %1, %3\n" \
> - "2:\n" \
> - " lw %2, %4\n" \
> - "3:\n" \
> - _ASM_EXTABLE_UACCESS_ERR_ZERO(1b, 3b, %0, %1) \
> - _ASM_EXTABLE_UACCESS_ERR_ZERO(2b, 3b, %0, %1) \
> - : "+r" (err), "=&r" (__lo), "=r" (__hi) \
> - : "m" (__ptr[__LSW]), "m" (__ptr[__MSW])); \
> - if (err) \
> - __hi = 0; \
> - (x) = (__typeof__(x))((__typeof__((x)-(x)))( \
> - (((u64)__hi << 32) | __lo))); \
> +#define __get_mem_8(x, ptr, err, type) \
> +do { \
> + u32 __user *__ptr = (u32 __user *)(ptr); \
> + u32 __lo, __hi; \
> + __asm__ __volatile__ ( \
> + "1:\n" \
> + " lw %1, %3\n" \
> + "2:\n" \
> + " lw %2, %4\n" \
> + "3:\n" \
> + _ASM_EXTABLE_##type##ACCESS_ERR_ZERO(1b, 3b, %0, %1) \
> + _ASM_EXTABLE_##type##ACCESS_ERR_ZERO(2b, 3b, %0, %1) \
> + : "+r" (err), "=&r" (__lo), "=r" (__hi) \
> + : "m" (__ptr[__LSW]), "m" (__ptr[__MSW])); \
> + if (err) \
> + __hi = 0; \
> + (x) = (__typeof__(x))((__typeof__((x)-(x)))( \
> + (((u64)__hi << 32) | __lo))); \
> } while (0)
> #endif /* CONFIG_64BIT */
>
> -#define __get_user_nocheck(x, __gu_ptr, __gu_err) \
> -do { \
> - switch (sizeof(*__gu_ptr)) { \
> - case 1: \
> - __get_user_asm("lb", (x), __gu_ptr, __gu_err); \
> - break; \
> - case 2: \
> - __get_user_asm("lh", (x), __gu_ptr, __gu_err); \
> - break; \
> - case 4: \
> - __get_user_asm("lw", (x), __gu_ptr, __gu_err); \
> - break; \
> - case 8: \
> - __get_user_8((x), __gu_ptr, __gu_err); \
> - break; \
> - default: \
> - BUILD_BUG(); \
> - } \
> +#define __get_mem_nocheck(x, __gu_ptr, __gu_err, type) \
> +do { \
> + switch (sizeof(*__gu_ptr)) { \
> + case 1: \
> + __get_mem_asm("lb", (x), __gu_ptr, __gu_err, type); \
> + break; \
> + case 2: \
> + __get_mem_asm("lh", (x), __gu_ptr, __gu_err, type); \
> + break; \
> + case 4: \
> + __get_mem_asm("lw", (x), __gu_ptr, __gu_err, type); \
> + break; \
> + case 8: \
> + __get_mem_8((x), __gu_ptr, __gu_err, type); \
> + break; \
> + default: \
> + BUILD_BUG(); \
> + } \
> } while (0)
>
> /**
> @@ -136,7 +136,7 @@ do { \
> __chk_user_ptr(__gu_ptr); \
> \
> __enable_user_access(); \
> - __get_user_nocheck(x, __gu_ptr, __gu_err); \
> + __get_mem_nocheck(x, __gu_ptr, __gu_err, U); \
> __disable_user_access(); \
> \
> __gu_err; \
> @@ -163,28 +163,28 @@ do { \
> ({ \
> const __typeof__(*(ptr)) __user *__p = (ptr); \
> might_fault(); \
> - access_ok(__p, sizeof(*__p)) ? \
> + access_ok(__p, sizeof(*__p)) ? \
> __get_user((x), __p) : \
> ((x) = 0, -EFAULT); \
> })
>
> -#define __put_user_asm(insn, x, ptr, err) \
> +#define __put_mem_asm(insn, x, ptr, err, type) \
> do { \
> __typeof__(*(ptr)) __x = x; \
> __asm__ __volatile__ ( \
> "1:\n" \
> " " insn " %z2, %1\n" \
> "2:\n" \
> - _ASM_EXTABLE_UACCESS_ERR(1b, 2b, %0) \
> + _ASM_EXTABLE_##type##ACCESS_ERR(1b, 2b, %0) \
> : "+r" (err), "=m" (*(ptr)) \
> : "rJ" (__x)); \
> } while (0)
>
> #ifdef CONFIG_64BIT
> -#define __put_user_8(x, ptr, err) \
> - __put_user_asm("sd", x, ptr, err)
> +#define __put_mem_8(x, ptr, err, type) \
> + __put_mem_asm("sd", x, ptr, err, type)
> #else /* !CONFIG_64BIT */
> -#define __put_user_8(x, ptr, err) \
> +#define __put_mem_8(x, ptr, err, type) \
> do { \
> u32 __user *__ptr = (u32 __user *)(ptr); \
> u64 __x = (__typeof__((x)-(x)))(x); \
> @@ -194,8 +194,8 @@ do { \
> "2:\n" \
> " sw %z4, %2\n" \
> "3:\n" \
> - _ASM_EXTABLE_UACCESS_ERR(1b, 3b, %0) \
> - _ASM_EXTABLE_UACCESS_ERR(2b, 3b, %0) \
> + _ASM_EXTABLE_##type##ACCESS_ERR(1b, 3b, %0) \
> + _ASM_EXTABLE_##type##ACCESS_ERR(2b, 3b, %0) \
> : "+r" (err), \
> "=m" (__ptr[__LSW]), \
> "=m" (__ptr[__MSW]) \
> @@ -203,24 +203,24 @@ do { \
> } while (0)
> #endif /* CONFIG_64BIT */
>
> -#define __put_user_nocheck(x, __gu_ptr, __pu_err) \
> -do { \
> - switch (sizeof(*__gu_ptr)) { \
> - case 1: \
> - __put_user_asm("sb", (x), __gu_ptr, __pu_err); \
> - break; \
> - case 2: \
> - __put_user_asm("sh", (x), __gu_ptr, __pu_err); \
> - break; \
> - case 4: \
> - __put_user_asm("sw", (x), __gu_ptr, __pu_err); \
> - break; \
> - case 8: \
> - __put_user_8((x), __gu_ptr, __pu_err); \
> - break; \
> - default: \
> - BUILD_BUG(); \
> - } \
> +#define __put_mem_nocheck(x, __gu_ptr, __pu_err, type) \
> +do { \
> + switch (sizeof(*__gu_ptr)) { \
> + case 1: \
> + __put_mem_asm("sb", (x), __gu_ptr, __pu_err, type); \
> + break; \
> + case 2: \
> + __put_mem_asm("sh", (x), __gu_ptr, __pu_err, type); \
> + break; \
> + case 4: \
> + __put_mem_asm("sw", (x), __gu_ptr, __pu_err, type); \
> + break; \
> + case 8: \
> + __put_mem_8((x), __gu_ptr, __pu_err, type); \
> + break; \
> + default: \
> + BUILD_BUG(); \
> + } \
> } while (0)
>
> /**
> @@ -253,7 +253,7 @@ do { \
> __chk_user_ptr(__gu_ptr); \
> \
> __enable_user_access(); \
> - __put_user_nocheck(__val, __gu_ptr, __pu_err); \
> + __put_mem_nocheck(__val, __gu_ptr, __pu_err, U); \
> __disable_user_access(); \
> \
> __pu_err; \
> @@ -279,7 +279,7 @@ do { \
> ({ \
> __typeof__(*(ptr)) __user *__p = (ptr); \
> might_fault(); \
> - access_ok(__p, sizeof(*__p)) ? \
> + access_ok(__p, sizeof(*__p)) ? \
> __put_user((x), __p) : \
> -EFAULT; \
> })
> @@ -321,7 +321,7 @@ unsigned long __must_check clear_user(void __user *to, unsigned long n)
> do { \
> long __kr_err; \
> \
> - __get_user_nocheck(*((type *)(dst)), (type *)(src), __kr_err); \
> + __get_mem_nocheck(*((type *)(dst)), (type *)(src), __kr_err, K);\
> if (unlikely(__kr_err)) \
> goto err_label; \
> } while (0)
> @@ -330,7 +330,7 @@ do { \
> do { \
> long __kr_err; \
> \
> - __put_user_nocheck(*((type *)(src)), (type *)(dst), __kr_err); \
> + __put_mem_nocheck(*((type *)(src)), (type *)(dst), __kr_err, K);\
> if (unlikely(__kr_err)) \
> goto err_label; \
> } while (0)
> --
> 2.25.1
>
>
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