diff options
Diffstat (limited to 'arch/arm/include/asm/uaccess.h')
| -rw-r--r-- | arch/arm/include/asm/uaccess.h | 649 |
1 files changed, 410 insertions, 239 deletions
diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h index 7e1f76027f66..d6ae80b5df36 100644 --- a/arch/arm/include/asm/uaccess.h +++ b/arch/arm/include/asm/uaccess.h @@ -1,9 +1,6 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ /* * arch/arm/include/asm/uaccess.h - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. */ #ifndef _ASMARM_UACCESS_H #define _ASMARM_UACCESS_H @@ -11,36 +8,77 @@ /* * User space memory access functions */ +#include <linux/kernel.h> #include <linux/string.h> -#include <linux/thread_info.h> -#include <asm/errno.h> -#include <asm/memory.h> +#include <asm/page.h> #include <asm/domain.h> +#include <linux/unaligned.h> #include <asm/unified.h> +#include <asm/pgtable.h> +#include <asm/proc-fns.h> #include <asm/compiler.h> -#define VERIFY_READ 0 -#define VERIFY_WRITE 1 +#include <asm/extable.h> /* - * The exception table consists of pairs of addresses: the first is the - * address of an instruction that is allowed to fault, and the second is - * the address at which the program should continue. No registers are - * modified, so it is entirely up to the continuation code to figure out - * what to do. - * - * All the routines below use bits of fixup code that are out of line - * with the main instruction path. This means when everything is well, - * we don't even have to jump over them. Further, they do not intrude - * on our cache or tlb entries. + * These two functions allow hooking accesses to userspace to increase + * system integrity by ensuring that the kernel can not inadvertantly + * perform such accesses (eg, via list poison values) which could then + * be exploited for priviledge escalation. */ +#if defined(CONFIG_CPU_SW_DOMAIN_PAN) + +static __always_inline unsigned int uaccess_save_and_enable(void) +{ + unsigned int old_domain = get_domain(); + + /* Set the current domain access to permit user accesses */ + set_domain((old_domain & ~domain_mask(DOMAIN_USER)) | + domain_val(DOMAIN_USER, DOMAIN_CLIENT)); + + return old_domain; +} + +static __always_inline void uaccess_restore(unsigned int flags) +{ + /* Restore the user access mask */ + set_domain(flags); +} + +#elif defined(CONFIG_CPU_TTBR0_PAN) + +static __always_inline unsigned int uaccess_save_and_enable(void) +{ + unsigned int old_ttbcr = cpu_get_ttbcr(); + + /* + * Enable TTBR0 page table walks (T0SZ = 0, EDP0 = 0) and ASID from + * TTBR0 (A1 = 0). + */ + cpu_set_ttbcr(old_ttbcr & ~(TTBCR_A1 | TTBCR_EPD0 | TTBCR_T0SZ_MASK)); + isb(); + + return old_ttbcr; +} + +static inline void uaccess_restore(unsigned int flags) +{ + cpu_set_ttbcr(flags); + isb(); +} + +#else + +static inline unsigned int uaccess_save_and_enable(void) +{ + return 0; +} -struct exception_table_entry +static inline void uaccess_restore(unsigned int flags) { - unsigned long insn, fixup; -}; +} -extern int fixup_exception(struct pt_regs *regs); +#endif /* * These two are intentionally not defined anywhere - if the kernel @@ -49,43 +87,42 @@ extern int fixup_exception(struct pt_regs *regs); extern int __get_user_bad(void); extern int __put_user_bad(void); -/* - * Note that this is actually 0x1,0000,0000 - */ -#define KERNEL_DS 0x00000000 -#define get_ds() (KERNEL_DS) - #ifdef CONFIG_MMU -#define USER_DS TASK_SIZE -#define get_fs() (current_thread_info()->addr_limit) +/* + * This is a type: either unsigned long, if the argument fits into + * that type, or otherwise unsigned long long. + */ +#define __inttype(x) \ + __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) -static inline void set_fs(mm_segment_t fs) +/* + * Sanitise a uaccess pointer such that it becomes NULL if addr+size + * is above the current addr_limit. + */ +#define uaccess_mask_range_ptr(ptr, size) \ + ((__typeof__(ptr))__uaccess_mask_range_ptr(ptr, size)) +static inline void __user *__uaccess_mask_range_ptr(const void __user *ptr, + size_t size) { - current_thread_info()->addr_limit = fs; - modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER); + void __user *safe_ptr = (void __user *)ptr; + unsigned long tmp; + + asm volatile( + " .syntax unified\n" + " sub %1, %3, #1\n" + " subs %1, %1, %0\n" + " addhs %1, %1, #1\n" + " subshs %1, %1, %2\n" + " movlo %0, #0\n" + : "+r" (safe_ptr), "=&r" (tmp) + : "r" (size), "r" (TASK_SIZE) + : "cc"); + + csdb(); + return safe_ptr; } -#define segment_eq(a,b) ((a) == (b)) - -#define __addr_ok(addr) ({ \ - unsigned long flag; \ - __asm__("cmp %2, %0; movlo %0, #0" \ - : "=&r" (flag) \ - : "0" (current_thread_info()->addr_limit), "r" (addr) \ - : "cc"); \ - (flag == 0); }) - -/* We use 33-bit arithmetic here... */ -#define __range_ok(addr,size) ({ \ - unsigned long flag, roksum; \ - __chk_user_ptr(addr); \ - __asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \ - : "=&r" (flag), "=&r" (roksum) \ - : "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \ - : "cc"); \ - flag; }) - /* * Single-value transfer routines. They automatically use the right * size if we just have the right pointer type. Note that the functions @@ -100,51 +137,93 @@ static inline void set_fs(mm_segment_t fs) extern int __get_user_1(void *); extern int __get_user_2(void *); extern int __get_user_4(void *); +extern int __get_user_32t_8(void *); +extern int __get_user_8(void *); +extern int __get_user_64t_1(void *); +extern int __get_user_64t_2(void *); +extern int __get_user_64t_4(void *); -#define __GUP_CLOBBER_1 "lr", "cc" -#ifdef CONFIG_CPU_USE_DOMAINS -#define __GUP_CLOBBER_2 "ip", "lr", "cc" +#define __get_user_x(__r2, __p, __e, __l, __s) \ + __asm__ __volatile__ ( \ + __asmeq("%0", "r0") __asmeq("%1", "r2") \ + __asmeq("%3", "r1") \ + "bl __get_user_" #__s \ + : "=&r" (__e), "=r" (__r2) \ + : "0" (__p), "r" (__l) \ + : "ip", "lr", "cc") + +/* narrowing a double-word get into a single 32bit word register: */ +#ifdef __ARMEB__ +#define __get_user_x_32t(__r2, __p, __e, __l, __s) \ + __get_user_x(__r2, __p, __e, __l, 32t_8) #else -#define __GUP_CLOBBER_2 "lr", "cc" +#define __get_user_x_32t __get_user_x #endif -#define __GUP_CLOBBER_4 "lr", "cc" -#define __get_user_x(__r2,__p,__e,__l,__s) \ +/* + * storing result into proper least significant word of 64bit target var, + * different only for big endian case where 64 bit __r2 lsw is r3: + */ +#ifdef __ARMEB__ +#define __get_user_x_64t(__r2, __p, __e, __l, __s) \ __asm__ __volatile__ ( \ __asmeq("%0", "r0") __asmeq("%1", "r2") \ __asmeq("%3", "r1") \ - "bl __get_user_" #__s \ + "bl __get_user_64t_" #__s \ : "=&r" (__e), "=r" (__r2) \ : "0" (__p), "r" (__l) \ - : __GUP_CLOBBER_##__s) + : "ip", "lr", "cc") +#else +#define __get_user_x_64t __get_user_x +#endif + -#define __get_user_check(x,p) \ +#define __get_user_check(x, p) \ ({ \ - unsigned long __limit = current_thread_info()->addr_limit - 1; \ - register const typeof(*(p)) __user *__p asm("r0") = (p);\ - register unsigned long __r2 asm("r2"); \ + unsigned long __limit = TASK_SIZE - 1; \ + register typeof(*(p)) __user *__p asm("r0") = (p); \ + register __inttype(x) __r2 asm("r2"); \ register unsigned long __l asm("r1") = __limit; \ register int __e asm("r0"); \ + unsigned int __ua_flags = uaccess_save_and_enable(); \ + int __tmp_e; \ switch (sizeof(*(__p))) { \ case 1: \ - __get_user_x(__r2, __p, __e, __l, 1); \ + if (sizeof((x)) >= 8) \ + __get_user_x_64t(__r2, __p, __e, __l, 1); \ + else \ + __get_user_x(__r2, __p, __e, __l, 1); \ break; \ case 2: \ - __get_user_x(__r2, __p, __e, __l, 2); \ + if (sizeof((x)) >= 8) \ + __get_user_x_64t(__r2, __p, __e, __l, 2); \ + else \ + __get_user_x(__r2, __p, __e, __l, 2); \ break; \ case 4: \ - __get_user_x(__r2, __p, __e, __l, 4); \ + if (sizeof((x)) >= 8) \ + __get_user_x_64t(__r2, __p, __e, __l, 4); \ + else \ + __get_user_x(__r2, __p, __e, __l, 4); \ + break; \ + case 8: \ + if (sizeof((x)) < 8) \ + __get_user_x_32t(__r2, __p, __e, __l, 4); \ + else \ + __get_user_x(__r2, __p, __e, __l, 8); \ break; \ default: __e = __get_user_bad(); break; \ } \ + __tmp_e = __e; \ + uaccess_restore(__ua_flags); \ x = (typeof(*(p))) __r2; \ - __e; \ + __tmp_e; \ }) -#define get_user(x,p) \ +#define get_user(x, p) \ ({ \ might_fault(); \ - __get_user_check(x,p); \ + __get_user_check(x, p); \ }) extern int __put_user_1(void *, unsigned int); @@ -152,71 +231,41 @@ extern int __put_user_2(void *, unsigned int); extern int __put_user_4(void *, unsigned int); extern int __put_user_8(void *, unsigned long long); -#define __put_user_x(__r2,__p,__e,__l,__s) \ - __asm__ __volatile__ ( \ - __asmeq("%0", "r0") __asmeq("%2", "r2") \ - __asmeq("%3", "r1") \ - "bl __put_user_" #__s \ - : "=&r" (__e) \ - : "0" (__p), "r" (__r2), "r" (__l) \ - : "ip", "lr", "cc") - -#define __put_user_check(x,p) \ +#define __put_user_check(__pu_val, __ptr, __err, __s) \ ({ \ - unsigned long __limit = current_thread_info()->addr_limit - 1; \ - register const typeof(*(p)) __r2 asm("r2") = (x); \ - register const typeof(*(p)) __user *__p asm("r0") = (p);\ + unsigned long __limit = TASK_SIZE - 1; \ + register typeof(__pu_val) __r2 asm("r2") = __pu_val; \ + register const void __user *__p asm("r0") = __ptr; \ register unsigned long __l asm("r1") = __limit; \ register int __e asm("r0"); \ - switch (sizeof(*(__p))) { \ - case 1: \ - __put_user_x(__r2, __p, __e, __l, 1); \ - break; \ - case 2: \ - __put_user_x(__r2, __p, __e, __l, 2); \ - break; \ - case 4: \ - __put_user_x(__r2, __p, __e, __l, 4); \ - break; \ - case 8: \ - __put_user_x(__r2, __p, __e, __l, 8); \ - break; \ - default: __e = __put_user_bad(); break; \ - } \ - __e; \ + __asm__ __volatile__ ( \ + __asmeq("%0", "r0") __asmeq("%2", "r2") \ + __asmeq("%3", "r1") \ + "bl __put_user_" #__s \ + : "=&r" (__e) \ + : "0" (__p), "r" (__r2), "r" (__l) \ + : "ip", "lr", "cc"); \ + __err = __e; \ }) -#define put_user(x,p) \ - ({ \ - might_fault(); \ - __put_user_check(x,p); \ - }) - #else /* CONFIG_MMU */ -/* - * uClinux has only one addr space, so has simplified address limits. - */ -#define USER_DS KERNEL_DS - -#define segment_eq(a,b) (1) -#define __addr_ok(addr) ((void)(addr),1) -#define __range_ok(addr,size) ((void)(addr),0) -#define get_fs() (KERNEL_DS) - -static inline void set_fs(mm_segment_t fs) -{ -} - -#define get_user(x,p) __get_user(x,p) -#define put_user(x,p) __put_user(x,p) +#define get_user(x, p) __get_user(x, p) +#define __put_user_check __put_user_nocheck #endif /* CONFIG_MMU */ -#define access_ok(type,addr,size) (__range_ok(addr,size) == 0) +#include <asm-generic/access_ok.h> -#define user_addr_max() \ - (segment_eq(get_fs(), USER_DS) ? TASK_SIZE : ~0UL) +#ifdef CONFIG_CPU_SPECTRE +/* + * When mitigating Spectre variant 1, it is not worth fixing the non- + * verifying accessors, because we need to add verification of the + * address space there. Force these to use the standard get_user() + * version instead. + */ +#define __get_user(x, ptr) get_user(x, ptr) +#else /* * The "__xxx" versions of the user access functions do not verify the @@ -227,39 +276,45 @@ static inline void set_fs(mm_segment_t fs) * error occurs, and leave it unchanged on success. Note that these * versions are void (ie, don't return a value as such). */ -#define __get_user(x,ptr) \ +#define __get_user(x, ptr) \ ({ \ long __gu_err = 0; \ - __get_user_err((x),(ptr),__gu_err); \ + __get_user_err((x), (ptr), __gu_err, TUSER()); \ __gu_err; \ }) -#define __get_user_error(x,ptr,err) \ -({ \ - __get_user_err((x),(ptr),err); \ - (void) 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_err(x,ptr,err) \ +#define __get_user_err(x, ptr, err, __t) \ do { \ unsigned long __gu_addr = (unsigned long)(ptr); \ - unsigned long __gu_val; \ + __long_type(x) __gu_val; \ + unsigned int __ua_flags; \ __chk_user_ptr(ptr); \ might_fault(); \ + __ua_flags = uaccess_save_and_enable(); \ switch (sizeof(*(ptr))) { \ - case 1: __get_user_asm_byte(__gu_val,__gu_addr,err); break; \ - case 2: __get_user_asm_half(__gu_val,__gu_addr,err); break; \ - case 4: __get_user_asm_word(__gu_val,__gu_addr,err); break; \ + case 1: __get_user_asm_byte(__gu_val, __gu_addr, err, __t); break; \ + case 2: __get_user_asm_half(__gu_val, __gu_addr, err, __t); break; \ + case 4: __get_user_asm_word(__gu_val, __gu_addr, err, __t); break; \ + case 8: __get_user_asm_dword(__gu_val, __gu_addr, err, __t); break; \ default: (__gu_val) = __get_user_bad(); \ } \ + uaccess_restore(__ua_flags); \ (x) = (__typeof__(*(ptr)))__gu_val; \ } while (0) +#endif -#define __get_user_asm_byte(x,addr,err) \ +#define __get_user_asm(x, addr, err, instr) \ __asm__ __volatile__( \ - "1: " TUSER(ldrb) " %1,[%2],#0\n" \ + "1: " instr " %1, [%2], #0\n" \ "2:\n" \ - " .pushsection .fixup,\"ax\"\n" \ + " .pushsection .text.fixup,\"ax\"\n" \ " .align 2\n" \ "3: mov %0, %3\n" \ " mov %1, #0\n" \ @@ -273,75 +328,112 @@ do { \ : "r" (addr), "i" (-EFAULT) \ : "cc") +#define __get_user_asm_byte(x, addr, err, __t) \ + __get_user_asm(x, addr, err, "ldrb" __t) + +#if __LINUX_ARM_ARCH__ >= 6 + +#define __get_user_asm_half(x, addr, err, __t) \ + __get_user_asm(x, addr, err, "ldrh" __t) + +#else + #ifndef __ARMEB__ -#define __get_user_asm_half(x,__gu_addr,err) \ +#define __get_user_asm_half(x, __gu_addr, err, __t) \ ({ \ unsigned long __b1, __b2; \ - __get_user_asm_byte(__b1, __gu_addr, err); \ - __get_user_asm_byte(__b2, __gu_addr + 1, err); \ + __get_user_asm_byte(__b1, __gu_addr, err, __t); \ + __get_user_asm_byte(__b2, __gu_addr + 1, err, __t); \ (x) = __b1 | (__b2 << 8); \ }) #else -#define __get_user_asm_half(x,__gu_addr,err) \ +#define __get_user_asm_half(x, __gu_addr, err, __t) \ ({ \ unsigned long __b1, __b2; \ - __get_user_asm_byte(__b1, __gu_addr, err); \ - __get_user_asm_byte(__b2, __gu_addr + 1, err); \ + __get_user_asm_byte(__b1, __gu_addr, err, __t); \ + __get_user_asm_byte(__b2, __gu_addr + 1, err, __t); \ (x) = (__b1 << 8) | __b2; \ }) #endif -#define __get_user_asm_word(x,addr,err) \ - __asm__ __volatile__( \ - "1: " TUSER(ldr) " %1,[%2],#0\n" \ - "2:\n" \ - " .pushsection .fixup,\"ax\"\n" \ - " .align 2\n" \ - "3: mov %0, %3\n" \ - " mov %1, #0\n" \ - " b 2b\n" \ - " .popsection\n" \ - " .pushsection __ex_table,\"a\"\n" \ - " .align 3\n" \ - " .long 1b, 3b\n" \ - " .popsection" \ - : "+r" (err), "=&r" (x) \ - : "r" (addr), "i" (-EFAULT) \ - : "cc") +#endif /* __LINUX_ARM_ARCH__ >= 6 */ + +#define __get_user_asm_word(x, addr, err, __t) \ + __get_user_asm(x, addr, err, "ldr" __t) -#define __put_user(x,ptr) \ +#ifdef __ARMEB__ +#define __WORD0_OFFS 4 +#define __WORD1_OFFS 0 +#else +#define __WORD0_OFFS 0 +#define __WORD1_OFFS 4 +#endif + +#define __get_user_asm_dword(x, addr, err, __t) \ + ({ \ + unsigned long __w0, __w1; \ + __get_user_asm(__w0, addr + __WORD0_OFFS, err, "ldr" __t); \ + __get_user_asm(__w1, addr + __WORD1_OFFS, err, "ldr" __t); \ + (x) = ((u64)__w1 << 32) | (u64) __w0; \ +}) + +#define __put_user_switch(x, ptr, __err, __fn) \ + do { \ + const __typeof__(*(ptr)) __user *__pu_ptr = (ptr); \ + __typeof__(*(ptr)) __pu_val = (x); \ + unsigned int __ua_flags; \ + might_fault(); \ + __ua_flags = uaccess_save_and_enable(); \ + switch (sizeof(*(ptr))) { \ + case 1: __fn(__pu_val, __pu_ptr, __err, 1); break; \ + case 2: __fn(__pu_val, __pu_ptr, __err, 2); break; \ + case 4: __fn(__pu_val, __pu_ptr, __err, 4); break; \ + case 8: __fn(__pu_val, __pu_ptr, __err, 8); break; \ + default: __err = __put_user_bad(); break; \ + } \ + uaccess_restore(__ua_flags); \ + } while (0) + +#define put_user(x, ptr) \ ({ \ - long __pu_err = 0; \ - __put_user_err((x),(ptr),__pu_err); \ + int __pu_err = 0; \ + __put_user_switch((x), (ptr), __pu_err, __put_user_check); \ __pu_err; \ }) -#define __put_user_error(x,ptr,err) \ +#ifdef CONFIG_CPU_SPECTRE +/* + * When mitigating Spectre variant 1.1, all accessors need to include + * verification of the address space. + */ +#define __put_user(x, ptr) put_user(x, ptr) + +#else +#define __put_user(x, ptr) \ ({ \ - __put_user_err((x),(ptr),err); \ - (void) 0; \ + long __pu_err = 0; \ + __put_user_switch((x), (ptr), __pu_err, __put_user_nocheck); \ + __pu_err; \ }) -#define __put_user_err(x,ptr,err) \ -do { \ - unsigned long __pu_addr = (unsigned long)(ptr); \ - __typeof__(*(ptr)) __pu_val = (x); \ - __chk_user_ptr(ptr); \ - might_fault(); \ - switch (sizeof(*(ptr))) { \ - case 1: __put_user_asm_byte(__pu_val,__pu_addr,err); break; \ - case 2: __put_user_asm_half(__pu_val,__pu_addr,err); break; \ - case 4: __put_user_asm_word(__pu_val,__pu_addr,err); break; \ - case 8: __put_user_asm_dword(__pu_val,__pu_addr,err); break; \ - default: __put_user_bad(); \ - } \ -} while (0) +#define __put_user_nocheck(x, __pu_ptr, __err, __size) \ + do { \ + unsigned long __pu_addr = (unsigned long)__pu_ptr; \ + __put_user_nocheck_##__size(x, __pu_addr, __err, TUSER());\ + } while (0) + +#define __put_user_nocheck_1 __put_user_asm_byte +#define __put_user_nocheck_2 __put_user_asm_half +#define __put_user_nocheck_4 __put_user_asm_word +#define __put_user_nocheck_8 __put_user_asm_dword + +#endif /* !CONFIG_CPU_SPECTRE */ -#define __put_user_asm_byte(x,__pu_addr,err) \ +#define __put_user_asm(x, __pu_addr, err, instr) \ __asm__ __volatile__( \ - "1: " TUSER(strb) " %1,[%2],#0\n" \ + "1: " instr " %1, [%2], #0\n" \ "2:\n" \ - " .pushsection .fixup,\"ax\"\n" \ + " .pushsection .text.fixup,\"ax\"\n" \ " .align 2\n" \ "3: mov %0, %3\n" \ " b 2b\n" \ @@ -354,38 +446,36 @@ do { \ : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \ : "cc") +#define __put_user_asm_byte(x, __pu_addr, err, __t) \ + __put_user_asm(x, __pu_addr, err, "strb" __t) + +#if __LINUX_ARM_ARCH__ >= 6 + +#define __put_user_asm_half(x, __pu_addr, err, __t) \ + __put_user_asm(x, __pu_addr, err, "strh" __t) + +#else + #ifndef __ARMEB__ -#define __put_user_asm_half(x,__pu_addr,err) \ +#define __put_user_asm_half(x, __pu_addr, err, __t) \ ({ \ - unsigned long __temp = (unsigned long)(x); \ - __put_user_asm_byte(__temp, __pu_addr, err); \ - __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \ + unsigned long __temp = (__force unsigned long)(x); \ + __put_user_asm_byte(__temp, __pu_addr, err, __t); \ + __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err, __t);\ }) #else -#define __put_user_asm_half(x,__pu_addr,err) \ +#define __put_user_asm_half(x, __pu_addr, err, __t) \ ({ \ - unsigned long __temp = (unsigned long)(x); \ - __put_user_asm_byte(__temp >> 8, __pu_addr, err); \ - __put_user_asm_byte(__temp, __pu_addr + 1, err); \ + unsigned long __temp = (__force unsigned long)(x); \ + __put_user_asm_byte(__temp >> 8, __pu_addr, err, __t); \ + __put_user_asm_byte(__temp, __pu_addr + 1, err, __t); \ }) #endif -#define __put_user_asm_word(x,__pu_addr,err) \ - __asm__ __volatile__( \ - "1: " TUSER(str) " %1,[%2],#0\n" \ - "2:\n" \ - " .pushsection .fixup,\"ax\"\n" \ - " .align 2\n" \ - "3: mov %0, %3\n" \ - " b 2b\n" \ - " .popsection\n" \ - " .pushsection __ex_table,\"a\"\n" \ - " .align 3\n" \ - " .long 1b, 3b\n" \ - " .popsection" \ - : "+r" (err) \ - : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \ - : "cc") +#endif /* __LINUX_ARM_ARCH__ >= 6 */ + +#define __put_user_asm_word(x, __pu_addr, err, __t) \ + __put_user_asm(x, __pu_addr, err, "str" __t) #ifndef __ARMEB__ #define __reg_oper0 "%R2" @@ -395,14 +485,14 @@ do { \ #define __reg_oper1 "%R2" #endif -#define __put_user_asm_dword(x,__pu_addr,err) \ +#define __put_user_asm_dword(x, __pu_addr, err, __t) \ __asm__ __volatile__( \ - ARM( "1: " TUSER(str) " " __reg_oper1 ", [%1], #4\n" ) \ - ARM( "2: " TUSER(str) " " __reg_oper0 ", [%1]\n" ) \ - THUMB( "1: " TUSER(str) " " __reg_oper1 ", [%1]\n" ) \ - THUMB( "2: " TUSER(str) " " __reg_oper0 ", [%1, #4]\n" ) \ + ARM( "1: str" __t " " __reg_oper1 ", [%1], #4\n" ) \ + ARM( "2: str" __t " " __reg_oper0 ", [%1]\n" ) \ + THUMB( "1: str" __t " " __reg_oper1 ", [%1]\n" ) \ + THUMB( "2: str" __t " " __reg_oper0 ", [%1, #4]\n" ) \ "3:\n" \ - " .pushsection .fixup,\"ax\"\n" \ + " .pushsection .text.fixup,\"ax\"\n" \ " .align 2\n" \ "4: mov %0, %3\n" \ " b 3b\n" \ @@ -416,48 +506,129 @@ do { \ : "r" (x), "i" (-EFAULT) \ : "cc") +#define __get_kernel_nofault(dst, src, type, err_label) \ +do { \ + const type *__pk_ptr = (src); \ + unsigned long __src = (unsigned long)(__pk_ptr); \ + type __val; \ + int __err = 0; \ + switch (sizeof(type)) { \ + case 1: __get_user_asm_byte(__val, __src, __err, ""); break; \ + case 2: __get_user_asm_half(__val, __src, __err, ""); break; \ + case 4: __get_user_asm_word(__val, __src, __err, ""); break; \ + case 8: { \ + u32 *__v32 = (u32*)&__val; \ + __get_user_asm_word(__v32[0], __src, __err, ""); \ + if (__err) \ + break; \ + __get_user_asm_word(__v32[1], __src+4, __err, ""); \ + break; \ + } \ + default: __err = __get_user_bad(); break; \ + } \ + if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) \ + put_unaligned(__val, (type *)(dst)); \ + else \ + *(type *)(dst) = __val; /* aligned by caller */ \ + if (__err) \ + goto err_label; \ +} while (0) + +#define __put_kernel_nofault(dst, src, type, err_label) \ +do { \ + const type *__pk_ptr = (dst); \ + unsigned long __dst = (unsigned long)__pk_ptr; \ + int __err = 0; \ + type __val = IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) \ + ? get_unaligned((type *)(src)) \ + : *(type *)(src); /* aligned by caller */ \ + switch (sizeof(type)) { \ + case 1: __put_user_asm_byte(__val, __dst, __err, ""); break; \ + case 2: __put_user_asm_half(__val, __dst, __err, ""); break; \ + case 4: __put_user_asm_word(__val, __dst, __err, ""); break; \ + case 8: __put_user_asm_dword(__val, __dst, __err, ""); break; \ + default: __err = __put_user_bad(); break; \ + } \ + if (__err) \ + goto err_label; \ +} while (0) #ifdef CONFIG_MMU -extern unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n); -extern unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n); -extern unsigned long __must_check __copy_to_user_std(void __user *to, const void *from, unsigned long n); -extern unsigned long __must_check __clear_user(void __user *addr, unsigned long n); -extern unsigned long __must_check __clear_user_std(void __user *addr, unsigned long n); -#else -#define __copy_from_user(to,from,n) (memcpy(to, (void __force *)from, n), 0) -#define __copy_to_user(to,from,n) (memcpy((void __force *)to, from, n), 0) -#define __clear_user(addr,n) (memset((void __force *)addr, 0, n), 0) -#endif +extern unsigned long __must_check +arm_copy_from_user(void *to, const void __user *from, unsigned long n); -static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n) +static inline unsigned long __must_check +raw_copy_from_user(void *to, const void __user *from, unsigned long n) { - if (access_ok(VERIFY_READ, from, n)) - n = __copy_from_user(to, from, n); - else /* security hole - plug it */ - memset(to, 0, n); + unsigned int __ua_flags; + + __ua_flags = uaccess_save_and_enable(); + n = arm_copy_from_user(to, from, n); + uaccess_restore(__ua_flags); return n; } -static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n) +extern unsigned long __must_check +arm_copy_to_user(void __user *to, const void *from, unsigned long n); +extern unsigned long __must_check +__copy_to_user_std(void __user *to, const void *from, unsigned long n); + +static inline unsigned long __must_check +raw_copy_to_user(void __user *to, const void *from, unsigned long n) { - if (access_ok(VERIFY_WRITE, to, n)) - n = __copy_to_user(to, from, n); +#ifndef CONFIG_UACCESS_WITH_MEMCPY + unsigned int __ua_flags; + __ua_flags = uaccess_save_and_enable(); + n = arm_copy_to_user(to, from, n); + uaccess_restore(__ua_flags); return n; +#else + return arm_copy_to_user(to, from, n); +#endif } -#define __copy_to_user_inatomic __copy_to_user -#define __copy_from_user_inatomic __copy_from_user +extern unsigned long __must_check +arm_clear_user(void __user *addr, unsigned long n); +extern unsigned long __must_check +__clear_user_std(void __user *addr, unsigned long n); + +static inline unsigned long __must_check +__clear_user(void __user *addr, unsigned long n) +{ + unsigned int __ua_flags = uaccess_save_and_enable(); + n = arm_clear_user(addr, n); + uaccess_restore(__ua_flags); + return n; +} + +#else +static inline unsigned long +raw_copy_from_user(void *to, const void __user *from, unsigned long n) +{ + memcpy(to, (const void __force *)from, n); + return 0; +} +static inline unsigned long +raw_copy_to_user(void __user *to, const void *from, unsigned long n) +{ + memcpy((void __force *)to, from, n); + return 0; +} +#define __clear_user(addr, n) (memset((void __force *)addr, 0, n), 0) +#endif +#define INLINE_COPY_TO_USER +#define INLINE_COPY_FROM_USER static inline unsigned long __must_check clear_user(void __user *to, unsigned long n) { - if (access_ok(VERIFY_WRITE, to, n)) + if (access_ok(to, n)) n = __clear_user(to, n); return n; } +/* These are from lib/ code, and use __get_user() and friends */ extern long strncpy_from_user(char *dest, const char __user *src, long count); -extern __must_check long strlen_user(const char __user *str); extern __must_check long strnlen_user(const char __user *str, long n); #endif /* _ASMARM_UACCESS_H */ |