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Diffstat (limited to 'arch/powerpc/include/asm/uaccess.h')
| -rw-r--r-- | arch/powerpc/include/asm/uaccess.h | 592 |
1 files changed, 592 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h new file mode 100644 index 000000000..6b808bcde --- /dev/null +++ b/arch/powerpc/include/asm/uaccess.h @@ -0,0 +1,592 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ARCH_POWERPC_UACCESS_H +#define _ARCH_POWERPC_UACCESS_H + +#include <asm/ppc_asm.h> +#include <asm/processor.h> +#include <asm/page.h> +#include <asm/extable.h> +#include <asm/kup.h> + +#ifdef __powerpc64__ +/* We use TASK_SIZE_USER64 as TASK_SIZE is not constant */ +#define TASK_SIZE_MAX TASK_SIZE_USER64 +#else +#define TASK_SIZE_MAX TASK_SIZE +#endif + +static inline bool __access_ok(unsigned long addr, unsigned long size) +{ + return addr < TASK_SIZE_MAX && size <= TASK_SIZE_MAX - addr; +} + +#define access_ok(addr, size) \ + (__chk_user_ptr(addr), \ + __access_ok((unsigned long)(addr), (size))) + +/* + * These are the main single-value transfer routines. They automatically + * use the right size if we just have the right pointer type. + * + * This gets kind of ugly. We want to return _two_ values in "get_user()" + * and yet we don't want to do any pointers, because that is too much + * of a performance impact. Thus we have a few rather ugly macros here, + * and hide all the ugliness from the user. + * + * The "__xxx" versions of the user access functions are versions that + * do not verify the address space, that must have been done previously + * with a separate "access_ok()" call (this is used when we do multiple + * accesses to the same area of user memory). + * + * As we use the same address space for kernel and user data on the + * PowerPC, we can just do these as direct assignments. (Of course, the + * exception handling means that it's no longer "just"...) + * + */ +#define get_user(x, ptr) \ + __get_user_check((x), (ptr), sizeof(*(ptr))) +#define put_user(x, ptr) \ + __put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) + +#define __get_user(x, ptr) \ + __get_user_nocheck((x), (ptr), sizeof(*(ptr)), true) +#define __put_user(x, ptr) \ + __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) +#define __put_user_goto(x, ptr, label) \ + __put_user_nocheck_goto((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), label) + +#define __get_user_allowed(x, ptr) \ + __get_user_nocheck((x), (ptr), sizeof(*(ptr)), false) + +#define __get_user_inatomic(x, ptr) \ + __get_user_nosleep((x), (ptr), sizeof(*(ptr))) +#define __put_user_inatomic(x, ptr) \ + __put_user_nosleep((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) + +#ifdef CONFIG_PPC64 + +#define ___get_user_instr(gu_op, dest, ptr) \ +({ \ + long __gui_ret = 0; \ + unsigned long __gui_ptr = (unsigned long)ptr; \ + struct ppc_inst __gui_inst; \ + unsigned int __prefix, __suffix; \ + __gui_ret = gu_op(__prefix, (unsigned int __user *)__gui_ptr); \ + if (__gui_ret == 0) { \ + if ((__prefix >> 26) == OP_PREFIX) { \ + __gui_ret = gu_op(__suffix, \ + (unsigned int __user *)__gui_ptr + 1); \ + __gui_inst = ppc_inst_prefix(__prefix, \ + __suffix); \ + } else { \ + __gui_inst = ppc_inst(__prefix); \ + } \ + if (__gui_ret == 0) \ + (dest) = __gui_inst; \ + } \ + __gui_ret; \ +}) + +#define get_user_instr(x, ptr) \ + ___get_user_instr(get_user, x, ptr) + +#define __get_user_instr(x, ptr) \ + ___get_user_instr(__get_user, x, ptr) + +#define __get_user_instr_inatomic(x, ptr) \ + ___get_user_instr(__get_user_inatomic, x, ptr) + +#else /* !CONFIG_PPC64 */ +#define get_user_instr(x, ptr) \ + get_user((x).val, (u32 __user *)(ptr)) + +#define __get_user_instr(x, ptr) \ + __get_user_nocheck((x).val, (u32 __user *)(ptr), sizeof(u32), true) + +#define __get_user_instr_inatomic(x, ptr) \ + __get_user_nosleep((x).val, (u32 __user *)(ptr), sizeof(u32)) + +#endif /* CONFIG_PPC64 */ + +extern long __put_user_bad(void); + +#define __put_user_size_allowed(x, ptr, size, retval) \ +do { \ + __label__ __pu_failed; \ + \ + retval = 0; \ + __put_user_size_goto(x, ptr, size, __pu_failed); \ + break; \ + \ +__pu_failed: \ + retval = -EFAULT; \ +} while (0) + +#define __put_user_size(x, ptr, size, retval) \ +do { \ + allow_write_to_user(ptr, size); \ + __put_user_size_allowed(x, ptr, size, retval); \ + prevent_write_to_user(ptr, size); \ +} while (0) + +#define __put_user_nocheck(x, ptr, size) \ +({ \ + long __pu_err; \ + __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ + __typeof__(*(ptr)) __pu_val = (x); \ + __typeof__(size) __pu_size = (size); \ + \ + if (!is_kernel_addr((unsigned long)__pu_addr)) \ + might_fault(); \ + __chk_user_ptr(__pu_addr); \ + __put_user_size(__pu_val, __pu_addr, __pu_size, __pu_err); \ + \ + __pu_err; \ +}) + +#define __put_user_check(x, ptr, size) \ +({ \ + long __pu_err = -EFAULT; \ + __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ + __typeof__(*(ptr)) __pu_val = (x); \ + __typeof__(size) __pu_size = (size); \ + \ + might_fault(); \ + if (access_ok(__pu_addr, __pu_size)) \ + __put_user_size(__pu_val, __pu_addr, __pu_size, __pu_err); \ + \ + __pu_err; \ +}) + +#define __put_user_nosleep(x, ptr, size) \ +({ \ + long __pu_err; \ + __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ + __typeof__(*(ptr)) __pu_val = (x); \ + __typeof__(size) __pu_size = (size); \ + \ + __chk_user_ptr(__pu_addr); \ + __put_user_size(__pu_val, __pu_addr, __pu_size, __pu_err); \ + \ + __pu_err; \ +}) + + +/* + * We don't tell gcc that we are accessing memory, but this is OK + * because we do not write to any memory gcc knows about, so there + * are no aliasing issues. + */ +#define __put_user_asm_goto(x, addr, label, op) \ + asm_volatile_goto( \ + "1: " op "%U1%X1 %0,%1 # put_user\n" \ + EX_TABLE(1b, %l2) \ + : \ + : "r" (x), "m"UPD_CONSTR (*addr) \ + : \ + : label) + +#ifdef __powerpc64__ +#define __put_user_asm2_goto(x, ptr, label) \ + __put_user_asm_goto(x, ptr, label, "std") +#else /* __powerpc64__ */ +#define __put_user_asm2_goto(x, addr, label) \ + asm_volatile_goto( \ + "1: stw%X1 %0, %1\n" \ + "2: stw%X1 %L0, %L1\n" \ + EX_TABLE(1b, %l2) \ + EX_TABLE(2b, %l2) \ + : \ + : "r" (x), "m" (*addr) \ + : \ + : label) +#endif /* __powerpc64__ */ + +#define __put_user_size_goto(x, ptr, size, label) \ +do { \ + switch (size) { \ + case 1: __put_user_asm_goto(x, ptr, label, "stb"); break; \ + case 2: __put_user_asm_goto(x, ptr, label, "sth"); break; \ + case 4: __put_user_asm_goto(x, ptr, label, "stw"); break; \ + case 8: __put_user_asm2_goto(x, ptr, label); break; \ + default: __put_user_bad(); \ + } \ +} while (0) + +#define __put_user_nocheck_goto(x, ptr, size, label) \ +do { \ + __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ + __chk_user_ptr(ptr); \ + __put_user_size_goto((x), __pu_addr, (size), label); \ +} while (0) + + +extern long __get_user_bad(void); + +/* + * This does an atomic 128 byte aligned load from userspace. + * Upto caller to do enable_kernel_vmx() before calling! + */ +#define __get_user_atomic_128_aligned(kaddr, uaddr, err) \ + __asm__ __volatile__( \ + ".machine push\n" \ + ".machine altivec\n" \ + "1: lvx 0,0,%1 # get user\n" \ + " stvx 0,0,%2 # put kernel\n" \ + ".machine pop\n" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3: li %0,%3\n" \ + " b 2b\n" \ + ".previous\n" \ + EX_TABLE(1b, 3b) \ + : "=r" (err) \ + : "b" (uaddr), "b" (kaddr), "i" (-EFAULT), "0" (err)) + +#define __get_user_asm(x, addr, err, op) \ + __asm__ __volatile__( \ + "1: "op"%U2%X2 %1, %2 # get_user\n" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3: li %0,%3\n" \ + " li %1,0\n" \ + " b 2b\n" \ + ".previous\n" \ + EX_TABLE(1b, 3b) \ + : "=r" (err), "=r" (x) \ + : "m"UPD_CONSTR (*addr), "i" (-EFAULT), "0" (err)) + +#ifdef __powerpc64__ +#define __get_user_asm2(x, addr, err) \ + __get_user_asm(x, addr, err, "ld") +#else /* __powerpc64__ */ +#define __get_user_asm2(x, addr, err) \ + __asm__ __volatile__( \ + "1: lwz%X2 %1, %2\n" \ + "2: lwz%X2 %L1, %L2\n" \ + "3:\n" \ + ".section .fixup,\"ax\"\n" \ + "4: li %0,%3\n" \ + " li %1,0\n" \ + " li %1+1,0\n" \ + " b 3b\n" \ + ".previous\n" \ + EX_TABLE(1b, 4b) \ + EX_TABLE(2b, 4b) \ + : "=r" (err), "=&r" (x) \ + : "m" (*addr), "i" (-EFAULT), "0" (err)) +#endif /* __powerpc64__ */ + +#define __get_user_size_allowed(x, ptr, size, retval) \ +do { \ + retval = 0; \ + __chk_user_ptr(ptr); \ + if (size > sizeof(x)) \ + (x) = __get_user_bad(); \ + switch (size) { \ + case 1: __get_user_asm(x, (u8 __user *)ptr, retval, "lbz"); break; \ + case 2: __get_user_asm(x, (u16 __user *)ptr, retval, "lhz"); break; \ + case 4: __get_user_asm(x, (u32 __user *)ptr, retval, "lwz"); break; \ + case 8: __get_user_asm2(x, (u64 __user *)ptr, retval); break; \ + default: (x) = __get_user_bad(); \ + } \ +} while (0) + +#define __get_user_size(x, ptr, size, retval) \ +do { \ + allow_read_from_user(ptr, size); \ + __get_user_size_allowed(x, ptr, size, retval); \ + prevent_read_from_user(ptr, size); \ +} while (0) + +/* + * This is a type: either unsigned long, if the argument fits into + * that type, or otherwise unsigned long long. + */ +#define __long_type(x) \ + __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) + +#define __get_user_nocheck(x, ptr, size, do_allow) \ +({ \ + long __gu_err; \ + __long_type(*(ptr)) __gu_val; \ + __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ + __typeof__(size) __gu_size = (size); \ + \ + __chk_user_ptr(__gu_addr); \ + if (do_allow && !is_kernel_addr((unsigned long)__gu_addr)) \ + might_fault(); \ + barrier_nospec(); \ + if (do_allow) \ + __get_user_size(__gu_val, __gu_addr, __gu_size, __gu_err); \ + else \ + __get_user_size_allowed(__gu_val, __gu_addr, __gu_size, __gu_err); \ + (x) = (__typeof__(*(ptr)))__gu_val; \ + \ + __gu_err; \ +}) + +#define __get_user_check(x, ptr, size) \ +({ \ + long __gu_err = -EFAULT; \ + __long_type(*(ptr)) __gu_val = 0; \ + __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ + __typeof__(size) __gu_size = (size); \ + \ + might_fault(); \ + if (access_ok(__gu_addr, __gu_size)) { \ + barrier_nospec(); \ + __get_user_size(__gu_val, __gu_addr, __gu_size, __gu_err); \ + } \ + (x) = (__force __typeof__(*(ptr)))__gu_val; \ + \ + __gu_err; \ +}) + +#define __get_user_nosleep(x, ptr, size) \ +({ \ + long __gu_err; \ + __long_type(*(ptr)) __gu_val; \ + __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ + __typeof__(size) __gu_size = (size); \ + \ + __chk_user_ptr(__gu_addr); \ + barrier_nospec(); \ + __get_user_size(__gu_val, __gu_addr, __gu_size, __gu_err); \ + (x) = (__force __typeof__(*(ptr)))__gu_val; \ + \ + __gu_err; \ +}) + + +/* more complex routines */ + +extern unsigned long __copy_tofrom_user(void __user *to, + const void __user *from, unsigned long size); + +#ifdef CONFIG_ARCH_HAS_COPY_MC +unsigned long __must_check +copy_mc_generic(void *to, const void *from, unsigned long size); + +static inline unsigned long __must_check +copy_mc_to_kernel(void *to, const void *from, unsigned long size) +{ + return copy_mc_generic(to, from, size); +} +#define copy_mc_to_kernel copy_mc_to_kernel + +static inline unsigned long __must_check +copy_mc_to_user(void __user *to, const void *from, unsigned long n) +{ + if (likely(check_copy_size(from, n, true))) { + if (access_ok(to, n)) { + allow_write_to_user(to, n); + n = copy_mc_generic((void *)to, from, n); + prevent_write_to_user(to, n); + } + } + + return n; +} +#endif + +#ifdef __powerpc64__ +static inline unsigned long +raw_copy_in_user(void __user *to, const void __user *from, unsigned long n) +{ + unsigned long ret; + + barrier_nospec(); + allow_read_write_user(to, from, n); + ret = __copy_tofrom_user(to, from, n); + prevent_read_write_user(to, from, n); + return ret; +} +#endif /* __powerpc64__ */ + +static inline unsigned long raw_copy_from_user(void *to, + const void __user *from, unsigned long n) +{ + unsigned long ret; + if (__builtin_constant_p(n) && (n <= 8)) { + ret = 1; + + switch (n) { + case 1: + barrier_nospec(); + __get_user_size(*(u8 *)to, from, 1, ret); + break; + case 2: + barrier_nospec(); + __get_user_size(*(u16 *)to, from, 2, ret); + break; + case 4: + barrier_nospec(); + __get_user_size(*(u32 *)to, from, 4, ret); + break; + case 8: + barrier_nospec(); + __get_user_size(*(u64 *)to, from, 8, ret); + break; + } + if (ret == 0) + return 0; + } + + barrier_nospec(); + allow_read_from_user(from, n); + ret = __copy_tofrom_user((__force void __user *)to, from, n); + prevent_read_from_user(from, n); + return ret; +} + +static inline unsigned long +raw_copy_to_user_allowed(void __user *to, const void *from, unsigned long n) +{ + if (__builtin_constant_p(n) && (n <= 8)) { + unsigned long ret = 1; + + switch (n) { + case 1: + __put_user_size_allowed(*(u8 *)from, (u8 __user *)to, 1, ret); + break; + case 2: + __put_user_size_allowed(*(u16 *)from, (u16 __user *)to, 2, ret); + break; + case 4: + __put_user_size_allowed(*(u32 *)from, (u32 __user *)to, 4, ret); + break; + case 8: + __put_user_size_allowed(*(u64 *)from, (u64 __user *)to, 8, ret); + break; + } + if (ret == 0) + return 0; + } + + return __copy_tofrom_user(to, (__force const void __user *)from, n); +} + +static inline unsigned long +raw_copy_to_user(void __user *to, const void *from, unsigned long n) +{ + unsigned long ret; + + allow_write_to_user(to, n); + ret = raw_copy_to_user_allowed(to, from, n); + prevent_write_to_user(to, n); + return ret; +} + +unsigned long __arch_clear_user(void __user *addr, unsigned long size); + +static inline unsigned long clear_user(void __user *addr, unsigned long size) +{ + unsigned long ret = size; + might_fault(); + if (likely(access_ok(addr, size))) { + allow_write_to_user(addr, size); + ret = __arch_clear_user(addr, size); + prevent_write_to_user(addr, size); + } + return ret; +} + +static inline unsigned long __clear_user(void __user *addr, unsigned long size) +{ + return clear_user(addr, size); +} + +extern long strncpy_from_user(char *dst, const char __user *src, long count); +extern __must_check long strnlen_user(const char __user *str, long n); + +extern long __copy_from_user_flushcache(void *dst, const void __user *src, + unsigned size); +extern void memcpy_page_flushcache(char *to, struct page *page, size_t offset, + size_t len); + +static __must_check inline bool user_access_begin(const void __user *ptr, size_t len) +{ + if (unlikely(!access_ok(ptr, len))) + return false; + + might_fault(); + + allow_read_write_user((void __user *)ptr, ptr, len); + return true; +} +#define user_access_begin user_access_begin +#define user_access_end prevent_current_access_user +#define user_access_save prevent_user_access_return +#define user_access_restore restore_user_access + +static __must_check inline bool +user_read_access_begin(const void __user *ptr, size_t len) +{ + if (unlikely(!access_ok(ptr, len))) + return false; + + might_fault(); + + allow_read_from_user(ptr, len); + return true; +} +#define user_read_access_begin user_read_access_begin +#define user_read_access_end prevent_current_read_from_user + +static __must_check inline bool +user_write_access_begin(const void __user *ptr, size_t len) +{ + if (unlikely(!access_ok(ptr, len))) + return false; + + might_fault(); + + allow_write_to_user((void __user *)ptr, len); + return true; +} +#define user_write_access_begin user_write_access_begin +#define user_write_access_end prevent_current_write_to_user + +#define unsafe_op_wrap(op, err) do { if (unlikely(op)) goto err; } while (0) +#define unsafe_get_user(x, p, e) unsafe_op_wrap(__get_user_allowed(x, p), e) +#define unsafe_put_user(x, p, e) __put_user_goto(x, p, e) + +#define unsafe_copy_to_user(d, s, l, e) \ +do { \ + u8 __user *_dst = (u8 __user *)(d); \ + const u8 *_src = (const u8 *)(s); \ + size_t _len = (l); \ + int _i; \ + \ + for (_i = 0; _i < (_len & ~(sizeof(long) - 1)); _i += sizeof(long)) \ + __put_user_goto(*(long*)(_src + _i), (long __user *)(_dst + _i), e);\ + if (IS_ENABLED(CONFIG_PPC64) && (_len & 4)) { \ + __put_user_goto(*(u32*)(_src + _i), (u32 __user *)(_dst + _i), e); \ + _i += 4; \ + } \ + if (_len & 2) { \ + __put_user_goto(*(u16*)(_src + _i), (u16 __user *)(_dst + _i), e); \ + _i += 2; \ + } \ + if (_len & 1) \ + __put_user_goto(*(u8*)(_src + _i), (u8 __user *)(_dst + _i), e);\ +} while (0) + +#define HAVE_GET_KERNEL_NOFAULT + +#define __get_kernel_nofault(dst, src, type, err_label) \ +do { \ + int __kr_err; \ + \ + __get_user_size_allowed(*((type *)(dst)), (__force type __user *)(src),\ + sizeof(type), __kr_err); \ + if (unlikely(__kr_err)) \ + goto err_label; \ +} while (0) + +#define __put_kernel_nofault(dst, src, type, err_label) \ + __put_user_size_goto(*((type *)(src)), \ + (__force type __user *)(dst), sizeof(type), err_label) + +#endif /* _ARCH_POWERPC_UACCESS_H */ |