cregit-Linux how code gets into the kernel

Release 4.14 arch/mips/include/asm/uaccess.h

/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1996, 1997, 1998, 1999, 2000, 03, 04 by Ralf Baechle
 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
 * Copyright (C) 2007  Maciej W. Rozycki
 * Copyright (C) 2014, Imagination Technologies Ltd.
 */
#ifndef _ASM_UACCESS_H

#define _ASM_UACCESS_H

#include <linux/kernel.h>
#include <linux/string.h>
#include <asm/asm-eva.h>
#include <asm/extable.h>

/*
 * The fs value determines whether argument validity checking should be
 * performed or not.  If get_fs() == USER_DS, checking is performed, with
 * get_fs() == KERNEL_DS, checking is bypassed.
 *
 * For historical reasons, these macros are grossly misnamed.
 */
#ifdef CONFIG_32BIT

#ifdef CONFIG_KVM_GUEST

#define __UA_LIMIT 0x40000000UL
#else

#define __UA_LIMIT 0x80000000UL
#endif


#define __UA_ADDR	".word"

#define __UA_LA		"la"

#define __UA_ADDU	"addu"

#define __UA_t0		"$8"

#define __UA_t1		"$9"

#endif /* CONFIG_32BIT */

#ifdef CONFIG_64BIT

extern u64 __ua_limit;


#define __UA_LIMIT	__ua_limit


#define __UA_ADDR	".dword"

#define __UA_LA		"dla"

#define __UA_ADDU	"daddu"

#define __UA_t0		"$12"

#define __UA_t1		"$13"

#endif /* CONFIG_64BIT */

/*
 * USER_DS is a bitmask that has the bits set that may not be set in a valid
 * userspace address.  Note that we limit 32-bit userspace to 0x7fff8000 but
 * the arithmetic we're doing only works if the limit is a power of two, so
 * we use 0x80000000 here on 32-bit kernels.  If a process passes an invalid
 * address in this range it's the process's problem, not ours :-)
 */

#ifdef CONFIG_KVM_GUEST

#define KERNEL_DS	((mm_segment_t) { 0x80000000UL })

#define USER_DS		((mm_segment_t) { 0xC0000000UL })
#else

#define KERNEL_DS	((mm_segment_t) { 0UL })

#define USER_DS		((mm_segment_t) { __UA_LIMIT })
#endif


#define get_ds()	(KERNEL_DS)

#define get_fs()	(current_thread_info()->addr_limit)

#define set_fs(x)	(current_thread_info()->addr_limit = (x))


#define segment_eq(a, b)	((a).seg == (b).seg)

/*
 * eva_kernel_access() - determine whether kernel memory access on an EVA system
 *
 * Determines whether memory accesses should be performed to kernel memory
 * on a system using Extended Virtual Addressing (EVA).
 *
 * Return: true if a kernel memory access on an EVA system, else false.
 */

static inline bool eva_kernel_access(void) { if (!IS_ENABLED(CONFIG_EVA)) return false; return uaccess_kernel(); }

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Paul Burton2291.67%133.33%
Masahiro Yamada14.17%133.33%
Al Viro14.17%133.33%
Total24100.00%3100.00%

/* * Is a address valid? This does a straightforward calculation rather * than tests. * * Address valid if: * - "addr" doesn't have any high-bits set * - AND "size" doesn't have any high-bits set * - AND "addr+size" doesn't have any high-bits set * - OR we are in kernel mode. * * __ua_size() is a trick to avoid runtime checking of positive constant * sizes; for those we already know at compile time that the size is ok. */ #define __ua_size(size) \ ((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size)) /* * access_ok: - Checks if a user space pointer is valid * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe * to write to a block, it is always safe to read from it. * @addr: User space pointer to start of block to check * @size: Size of block to check * * Context: User context only. This function may sleep if pagefaults are * enabled. * * Checks if a pointer to a block of memory in user space is valid. * * Returns true (nonzero) if the memory block may be valid, false (zero) * if it is definitely invalid. * * Note that, depending on architecture, this function probably just * checks that the pointer is in the user space range - after calling * this function, memory access functions may still return -EFAULT. */
static inline int __access_ok(const void __user *p, unsigned long size) { unsigned long addr = (unsigned long)p; return (get_fs().seg & (addr | (addr + size) | __ua_size(size))) == 0; }

Contributors

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Al Viro4790.38%150.00%
Andrew Morton59.62%150.00%
Total52100.00%2100.00%

#define access_ok(type, addr, size) \ likely(__access_ok((addr), (size))) /* * put_user: - Write a simple value into user space. * @x: Value to copy to user space. * @ptr: Destination address, in user space. * * Context: User context only. This function may sleep if pagefaults are * enabled. * * This macro copies a single simple value from kernel space to user * space. It supports simple types like char and int, but not larger * data types like structures or arrays. * * @ptr must have pointer-to-simple-variable type, and @x must be assignable * to the result of dereferencing @ptr. * * Returns zero on success, or -EFAULT on error. */ #define put_user(x,ptr) \ __put_user_check((x), (ptr), sizeof(*(ptr))) /* * get_user: - Get a simple variable from user space. * @x: Variable to store result. * @ptr: Source address, in user space. * * Context: User context only. This function may sleep if pagefaults are * enabled. * * This macro copies a single simple variable from user space to kernel * space. It supports simple types like char and int, but not larger * data types like structures or arrays. * * @ptr must have pointer-to-simple-variable type, and the result of * dereferencing @ptr must be assignable to @x without a cast. * * Returns zero on success, or -EFAULT on error. * On error, the variable @x is set to zero. */ #define get_user(x,ptr) \ __get_user_check((x), (ptr), sizeof(*(ptr))) /* * __put_user: - Write a simple value into user space, with less checking. * @x: Value to copy to user space. * @ptr: Destination address, in user space. * * Context: User context only. This function may sleep if pagefaults are * enabled. * * This macro copies a single simple value from kernel space to user * space. It supports simple types like char and int, but not larger * data types like structures or arrays. * * @ptr must have pointer-to-simple-variable type, and @x must be assignable * to the result of dereferencing @ptr. * * Caller must check the pointer with access_ok() before calling this * function. * * Returns zero on success, or -EFAULT on error. */ #define __put_user(x,ptr) \ __put_user_nocheck((x), (ptr), sizeof(*(ptr))) /* * __get_user: - Get a simple variable from user space, with less checking. * @x: Variable to store result. * @ptr: Source address, in user space. * * Context: User context only. This function may sleep if pagefaults are * enabled. * * This macro copies a single simple variable from user space to kernel * space. It supports simple types like char and int, but not larger * data types like structures or arrays. * * @ptr must have pointer-to-simple-variable type, and the result of * dereferencing @ptr must be assignable to @x without a cast. * * Caller must check the pointer with access_ok() before calling this * function. * * Returns zero on success, or -EFAULT on error. * On error, the variable @x is set to zero. */ #define __get_user(x,ptr) \ __get_user_nocheck((x), (ptr), sizeof(*(ptr))) struct __large_struct { unsigned long buf[100]; }; #define __m(x) (*(struct __large_struct __user *)(x)) /* * Yuck. We need two variants, one for 64bit operation and one * for 32 bit mode and old iron. */ #ifndef CONFIG_EVA #define __get_kernel_common(val, size, ptr) __get_user_common(val, size, ptr) #else /* * Kernel specific functions for EVA. We need to use normal load instructions * to read data from kernel when operating in EVA mode. We use these macros to * avoid redefining __get_user_asm for EVA. */ #undef _loadd #undef _loadw #undef _loadh #undef _loadb #ifdef CONFIG_32BIT #define _loadd _loadw #else #define _loadd(reg, addr) "ld " reg ", " addr #endif #define _loadw(reg, addr) "lw " reg ", " addr #define _loadh(reg, addr) "lh " reg ", " addr #define _loadb(reg, addr) "lb " reg ", " addr #define __get_kernel_common(val, size, ptr) \ do { \ switch (size) { \ case 1: __get_data_asm(val, _loadb, ptr); break; \ case 2: __get_data_asm(val, _loadh, ptr); break; \ case 4: __get_data_asm(val, _loadw, ptr); break; \ case 8: __GET_DW(val, _loadd, ptr); break; \ default: __get_user_unknown(); break; \ } \ } while (0) #endif #ifdef CONFIG_32BIT #define __GET_DW(val, insn, ptr) __get_data_asm_ll32(val, insn, ptr) #endif #ifdef CONFIG_64BIT #define __GET_DW(val, insn, ptr) __get_data_asm(val, insn, ptr) #endif extern void __get_user_unknown(void); #define __get_user_common(val, size, ptr) \ do { \ switch (size) { \ case 1: __get_data_asm(val, user_lb, ptr); break; \ case 2: __get_data_asm(val, user_lh, ptr); break; \ case 4: __get_data_asm(val, user_lw, ptr); break; \ case 8: __GET_DW(val, user_ld, ptr); break; \ default: __get_user_unknown(); break; \ } \ } while (0) #define __get_user_nocheck(x, ptr, size) \ ({ \ int __gu_err; \ \ if (eva_kernel_access()) { \ __get_kernel_common((x), size, ptr); \ } else { \ __chk_user_ptr(ptr); \ __get_user_common((x), size, ptr); \ } \ __gu_err; \ }) #define __get_user_check(x, ptr, size) \ ({ \ int __gu_err = -EFAULT; \ const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \ \ might_fault(); \ if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) { \ if (eva_kernel_access()) \ __get_kernel_common((x), size, __gu_ptr); \ else \ __get_user_common((x), size, __gu_ptr); \ } else \ (x) = 0; \ \ __gu_err; \ }) #define __get_data_asm(val, insn, addr) \ { \ long __gu_tmp; \ \ __asm__ __volatile__( \ "1: "insn("%1", "%3")" \n" \ "2: \n" \ " .insn \n" \ " .section .fixup,\"ax\" \n" \ "3: li %0, %4 \n" \ " move %1, $0 \n" \ " j 2b \n" \ " .previous \n" \ " .section __ex_table,\"a\" \n" \ " "__UA_ADDR "\t1b, 3b \n" \ " .previous \n" \ : "=r" (__gu_err), "=r" (__gu_tmp) \ : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \ \ (val) = (__typeof__(*(addr))) __gu_tmp; \ } /* * Get a long long 64 using 32 bit registers. */ #define __get_data_asm_ll32(val, insn, addr) \ { \ union { \ unsigned long long l; \ __typeof__(*(addr)) t; \ } __gu_tmp; \ \ __asm__ __volatile__( \ "1: " insn("%1", "(%3)")" \n" \ "2: " insn("%D1", "4(%3)")" \n" \ "3: \n" \ " .insn \n" \ " .section .fixup,\"ax\" \n" \ "4: li %0, %4 \n" \ " move %1, $0 \n" \ " move %D1, $0 \n" \ " j 3b \n" \ " .previous \n" \ " .section __ex_table,\"a\" \n" \ " " __UA_ADDR " 1b, 4b \n" \ " " __UA_ADDR " 2b, 4b \n" \ " .previous \n" \ : "=r" (__gu_err), "=&r" (__gu_tmp.l) \ : "0" (0), "r" (addr), "i" (-EFAULT)); \ \ (val) = __gu_tmp.t; \ } #ifndef CONFIG_EVA #define __put_kernel_common(ptr, size) __put_user_common(ptr, size) #else /* * Kernel specific functions for EVA. We need to use normal load instructions * to read data from kernel when operating in EVA mode. We use these macros to * avoid redefining __get_data_asm for EVA. */ #undef _stored #undef _storew #undef _storeh #undef _storeb #ifdef CONFIG_32BIT #define _stored _storew #else #define _stored(reg, addr) "ld " reg ", " addr #endif #define _storew(reg, addr) "sw " reg ", " addr #define _storeh(reg, addr) "sh " reg ", " addr #define _storeb(reg, addr) "sb " reg ", " addr #define __put_kernel_common(ptr, size) \ do { \ switch (size) { \ case 1: __put_data_asm(_storeb, ptr); break; \ case 2: __put_data_asm(_storeh, ptr); break; \ case 4: __put_data_asm(_storew, ptr); break; \ case 8: __PUT_DW(_stored, ptr); break; \ default: __put_user_unknown(); break; \ } \ } while(0) #endif /* * Yuck. We need two variants, one for 64bit operation and one * for 32 bit mode and old iron. */ #ifdef CONFIG_32BIT #define __PUT_DW(insn, ptr) __put_data_asm_ll32(insn, ptr) #endif #ifdef CONFIG_64BIT #define __PUT_DW(insn, ptr) __put_data_asm(insn, ptr) #endif #define __put_user_common(ptr, size) \ do { \ switch (size) { \ case 1: __put_data_asm(user_sb, ptr); break; \ case 2: __put_data_asm(user_sh, ptr); break; \ case 4: __put_data_asm(user_sw, ptr); break; \ case 8: __PUT_DW(user_sd, ptr); break; \ default: __put_user_unknown(); break; \ } \ } while (0) #define __put_user_nocheck(x, ptr, size) \ ({ \ __typeof__(*(ptr)) __pu_val; \ int __pu_err = 0; \ \ __pu_val = (x); \ if (eva_kernel_access()) { \ __put_kernel_common(ptr, size); \ } else { \ __chk_user_ptr(ptr); \ __put_user_common(ptr, size); \ } \ __pu_err; \ }) #define __put_user_check(x, ptr, size) \ ({ \ __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ __typeof__(*(ptr)) __pu_val = (x); \ int __pu_err = -EFAULT; \ \ might_fault(); \ if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) { \ if (eva_kernel_access()) \ __put_kernel_common(__pu_addr, size); \ else \ __put_user_common(__pu_addr, size); \ } \ \ __pu_err; \ }) #define __put_data_asm(insn, ptr) \ { \ __asm__ __volatile__( \ "1: "insn("%z2", "%3")" # __put_data_asm \n" \ "2: \n" \ " .insn \n" \ " .section .fixup,\"ax\" \n" \ "3: li %0, %4 \n" \ " j 2b \n" \ " .previous \n" \ " .section __ex_table,\"a\" \n" \ " " __UA_ADDR " 1b, 3b \n" \ " .previous \n" \ : "=r" (__pu_err) \ : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \ "i" (-EFAULT)); \ } #define __put_data_asm_ll32(insn, ptr) \ { \ __asm__ __volatile__( \ "1: "insn("%2", "(%3)")" # __put_data_asm_ll32 \n" \ "2: "insn("%D2", "4(%3)")" \n" \ "3: \n" \ " .insn \n" \ " .section .fixup,\"ax\" \n" \ "4: li %0, %4 \n" \ " j 3b \n" \ " .previous \n" \ " .section __ex_table,\"a\" \n" \ " " __UA_ADDR " 1b, 4b \n" \ " " __UA_ADDR " 2b, 4b \n" \ " .previous" \ : "=r" (__pu_err) \ : "0" (0), "r" (__pu_val), "r" (ptr), \ "i" (-EFAULT)); \ } extern void __put_user_unknown(void); /* * We're generating jump to subroutines which will be outside the range of * jump instructions */ #ifdef MODULE #define __MODULE_JAL(destination) \ ".set\tnoat\n\t" \ __UA_LA "\t$1, " #destination "\n\t" \ "jalr\t$1\n\t" \ ".set\tat\n\t" #else #define __MODULE_JAL(destination) \ "jal\t" #destination "\n\t" #endif #if defined(CONFIG_CPU_DADDI_WORKAROUNDS) || (defined(CONFIG_EVA) && \ defined(CONFIG_CPU_HAS_PREFETCH)) #define DADDI_SCRATCH "$3" #else #define DADDI_SCRATCH "$0" #endif extern size_t __copy_user(void *__to, const void *__from, size_t __n); #define __invoke_copy_from(func, to, from, n) \ ({ \ register void *__cu_to_r __asm__("$4"); \ register const void __user *__cu_from_r __asm__("$5"); \ register long __cu_len_r __asm__("$6"); \ \ __cu_to_r = (to); \ __cu_from_r = (from); \ __cu_len_r = (n); \ __asm__ __volatile__( \ ".set\tnoreorder\n\t" \ __MODULE_JAL(func) \ ".set\tnoat\n\t" \ __UA_ADDU "\t$1, %1, %2\n\t" \ ".set\tat\n\t" \ ".set\treorder" \ : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \ : \ : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \ DADDI_SCRATCH, "memory"); \ __cu_len_r; \ }) #define __invoke_copy_to(func, to, from, n) \ ({ \ register void __user *__cu_to_r __asm__("$4"); \ register const void *__cu_from_r __asm__("$5"); \ register long __cu_len_r __asm__("$6"); \ \ __cu_to_r = (to); \ __cu_from_r = (from); \ __cu_len_r = (n); \ __asm__ __volatile__( \ __MODULE_JAL(func) \ : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \ : \ : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \ DADDI_SCRATCH, "memory"); \ __cu_len_r; \ }) #define __invoke_copy_from_kernel(to, from, n) \ __invoke_copy_from(__copy_user, to, from, n) #define __invoke_copy_to_kernel(to, from, n) \ __invoke_copy_to(__copy_user, to, from, n) #define ___invoke_copy_in_kernel(to, from, n) \ __invoke_copy_from(__copy_user, to, from, n) #ifndef CONFIG_EVA #define __invoke_copy_from_user(to, from, n) \ __invoke_copy_from(__copy_user, to, from, n) #define __invoke_copy_to_user(to, from, n) \ __invoke_copy_to(__copy_user, to, from, n) #define ___invoke_copy_in_user(to, from, n) \ __invoke_copy_from(__copy_user, to, from, n) #else /* EVA specific functions */ extern size_t __copy_from_user_eva(void *__to, const void *__from, size_t __n); extern size_t __copy_to_user_eva(void *__to, const void *__from, size_t __n); extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n); /* * Source or destination address is in userland. We need to go through * the TLB */ #define __invoke_copy_from_user(to, from, n) \ __invoke_copy_from(__copy_from_user_eva, to, from, n) #define __invoke_copy_to_user(to, from, n) \ __invoke_copy_to(__copy_to_user_eva, to, from, n) #define ___invoke_copy_in_user(to, from, n) \ __invoke_copy_from(__copy_in_user_eva, to, from, n) #endif /* CONFIG_EVA */
static inline unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long n) { if (eva_kernel_access()) return __invoke_copy_to_kernel(to, from, n); else return __invoke_copy_to_user(to, from, n); }

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Al Viro3572.92%150.00%
Markos Chandras1327.08%150.00%
Total48100.00%2100.00%


static inline unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n) { if (eva_kernel_access()) return __invoke_copy_from_kernel(to, from, n); else return __invoke_copy_from_user(to, from, n); }

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PersonTokensPropCommitsCommitProp
Al Viro3572.92%125.00%
Markos Chandras714.58%125.00%
Linus Torvalds (pre-git)36.25%125.00%
Ralf Bächle36.25%125.00%
Total48100.00%4100.00%

#define INLINE_COPY_FROM_USER #define INLINE_COPY_TO_USER
static inline unsigned long raw_copy_in_user(void __user*to, const void __user *from, unsigned long n) { if (eva_kernel_access()) return ___invoke_copy_in_kernel(to, from, n); else return ___invoke_copy_in_user(to, from, n); }

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PersonTokensPropCommitsCommitProp
Al Viro4285.71%150.00%
Andrew Morton714.29%150.00%
Total49100.00%2100.00%

extern __kernel_size_t __bzero_kernel(void __user *addr, __kernel_size_t size); extern __kernel_size_t __bzero(void __user *addr, __kernel_size_t size); /* * __clear_user: - Zero a block of memory in user space, with less checking. * @to: Destination address, in user space. * @n: Number of bytes to zero. * * Zero a block of memory in user space. Caller must check * the specified block with access_ok() before calling this function. * * Returns number of bytes that could not be cleared. * On success, this will be zero. */
static inline __kernel_size_t __clear_user(void __user *addr, __kernel_size_t size) { __kernel_size_t res; if (eva_kernel_access()) { __asm__ __volatile__( "move\t$4, %1\n\t" "move\t$5, $0\n\t" "move\t$6, %2\n\t" __MODULE_JAL(__bzero_kernel) "move\t%0, $6" : "=r" (res) : "r" (addr), "r" (size) : "$4", "$5", "$6", __UA_t0, __UA_t1, "$31"); } else { might_fault(); __asm__ __volatile__( "move\t$4, %1\n\t" "move\t$5, $0\n\t" "move\t$6, %2\n\t" __MODULE_JAL(__bzero) "move\t%0, $6" : "=r" (res) : "r" (addr), "r" (size) : "$4", "$5", "$6", __UA_t0, __UA_t1, "$31"); } return res; }

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PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)2152.50%228.57%
James Hogan1435.00%114.29%
Ralf Bächle37.50%342.86%
Andrew Morton25.00%114.29%
Total40100.00%7100.00%

#define clear_user(addr,n) \ ({ \ void __user * __cl_addr = (addr); \ unsigned long __cl_size = (n); \ if (__cl_size && access_ok(VERIFY_WRITE, \ __cl_addr, __cl_size)) \ __cl_size = __clear_user(__cl_addr, __cl_size); \ __cl_size; \ }) extern long __strncpy_from_kernel_asm(char *__to, const char __user *__from, long __len); extern long __strncpy_from_user_asm(char *__to, const char __user *__from, long __len); /* * strncpy_from_user: - Copy a NUL terminated string from userspace. * @dst: Destination address, in kernel space. This buffer must be at * least @count bytes long. * @src: Source address, in user space. * @count: Maximum number of bytes to copy, including the trailing NUL. * * Copies a NUL-terminated string from userspace to kernel space. * * On success, returns the length of the string (not including the trailing * NUL). * * If access to userspace fails, returns -EFAULT (some data may have been * copied). * * If @count is smaller than the length of the string, copies @count bytes * and returns @count. */
static inline long strncpy_from_user(char *__to, const char __user *__from, long __len) { long res; if (eva_kernel_access()) { __asm__ __volatile__( "move\t$4, %1\n\t" "move\t$5, %2\n\t" "move\t$6, %3\n\t" __MODULE_JAL(__strncpy_from_kernel_asm) "move\t%0, $2" : "=r" (res) : "r" (__to), "r" (__from), "r" (__len) : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory"); } else { might_fault(); __asm__ __volatile__( "move\t$4, %1\n\t" "move\t$5, %2\n\t" "move\t$6, %3\n\t" __MODULE_JAL(__strncpy_from_user_asm) "move\t%0, $2" : "=r" (res) : "r" (__to), "r" (__from), "r" (__len) : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory"); } return res; }

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Linus Torvalds (pre-git)2657.78%225.00%
Markos Chandras1328.89%112.50%
Ralf Bächle36.67%337.50%
Andrew Morton24.44%112.50%
Paul Burton12.22%112.50%
Total45100.00%8100.00%

extern long __strnlen_kernel_asm(const char __user *s, long n); extern long __strnlen_user_asm(const char __user *s, long n); /* * strnlen_user: - Get the size of a string in user space. * @str: The string to measure. * * Context: User context only. This function may sleep if pagefaults are * enabled. * * Get the size of a NUL-terminated string in user space. * * Returns the size of the string INCLUDING the terminating NUL. * On exception, returns 0. * If the string is too long, returns a value greater than @n. */
static inline long strnlen_user(const char __user *s, long n) { long res; might_fault(); if (eva_kernel_access()) { __asm__ __volatile__( "move\t$4, %1\n\t" "move\t$5, %2\n\t" __MODULE_JAL(__strnlen_kernel_asm) "move\t%0, $2" : "=r" (res) : "r" (s), "r" (n) : "$2", "$4", "$5", __UA_t0, "$31"); } else { __asm__ __volatile__( "move\t$4, %1\n\t" "move\t$5, %2\n\t" __MODULE_JAL(__strnlen_user_asm) "move\t%0, $2" : "=r" (res) : "r" (s), "r" (n) : "$2", "$4", "$5", __UA_t0, "$31"); } return res; }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)2253.66%114.29%
Markos Chandras1331.71%114.29%
Ralf Bächle37.32%342.86%
Andrew Morton24.88%114.29%
Paul Burton12.44%114.29%
Total41100.00%7100.00%

#endif /* _ASM_UACCESS_H */

Overall Contributors

PersonTokensPropCommitsCommitProp
Markos Chandras39129.49%715.56%
Linus Torvalds (pre-git)29922.55%613.33%
Al Viro21616.29%715.56%
Ralf Bächle17513.20%1124.44%
Arnd Bergmann906.79%12.22%
Andrew Morton574.30%24.44%
Paul Burton292.19%12.22%
Sanjay Lal261.96%12.22%
James Hogan141.06%12.22%
Maciej W. Rozycki110.83%12.22%
David Hildenbrand60.45%12.22%
David Daney50.38%12.22%
Linus Torvalds20.15%12.22%
Ingo Molnar20.15%12.22%
Masahiro Yamada10.08%12.22%
Adam Buchbinder10.08%12.22%
Wu Zhangjin10.08%12.22%
Total1326100.00%45100.00%
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