linux_dsm_epyc7002/arch/mips/include/asm/uaccess.h

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/*
* 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.
[MIPS] R4000/R4400 daddiu erratum workaround This complements the generic R4000/R4400 errata workaround code and adds bits for the daddiu problem. In most places it just modifies handwritten assembly code so that the assembler is allowed to use a temporary register as daddiu may now be treated as a macro that expands to a sequence of li and daddu. It is the AT register or, where AT is unavailable or used explicitly for another purpose, an explicitly-named register is selected, using the .set at=<reg> feature added recently to gas. This feature is only used if CONFIG_CPU_DADDI_WORKAROUNDS has been set, so if the workaround remains disabled, the required version of binutils stays unchanged. Similarly, daddiu instructions put in branch delay slots in noreorder fragments are now taken out of them and the assembler is allowed to reorder them itself as possible (which it does making the whole idea of scheduling them into delay slots manually questionable). Also in the very few places where such a simple conversion was not possible, a handcoded longer sequence is implemented. Other than that there are changes to code responsible for building the TLB fault and page clear/copy handlers to avoid daddiu as appropriate. These are only effective if the erratum is verified to be present at the run time. Finally there is a trivial update to __delay(), because it uses daddiu in a branch delay slot. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-23 18:43:25 +07:00
* 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/errno.h>
#include <linux/thread_info.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 VERIFY_READ 0
#define VERIFY_WRITE 1
#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)
{
tree-wide: replace config_enabled() with IS_ENABLED() The use of config_enabled() against config options is ambiguous. In practical terms, config_enabled() is equivalent to IS_BUILTIN(), but the author might have used it for the meaning of IS_ENABLED(). Using IS_ENABLED(), IS_BUILTIN(), IS_MODULE() etc. makes the intention clearer. This commit replaces config_enabled() with IS_ENABLED() where possible. This commit is only touching bool config options. I noticed two cases where config_enabled() is used against a tristate option: - config_enabled(CONFIG_HWMON) [ drivers/net/wireless/ath/ath10k/thermal.c ] - config_enabled(CONFIG_BACKLIGHT_CLASS_DEVICE) [ drivers/gpu/drm/gma500/opregion.c ] I did not touch them because they should be converted to IS_BUILTIN() in order to keep the logic, but I was not sure it was the authors' intention. Link: http://lkml.kernel.org/r/1465215656-20569-1-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Stas Sergeev <stsp@list.ru> Cc: Matt Redfearn <matt.redfearn@imgtec.com> Cc: Joshua Kinard <kumba@gentoo.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Borislav Petkov <bp@suse.de> Cc: Markos Chandras <markos.chandras@imgtec.com> Cc: "Dmitry V. Levin" <ldv@altlinux.org> Cc: yu-cheng yu <yu-cheng.yu@intel.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Will Drewry <wad@chromium.org> Cc: Nikolay Martynov <mar.kolya@gmail.com> Cc: Huacai Chen <chenhc@lemote.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Cc: Rafal Milecki <zajec5@gmail.com> Cc: James Cowgill <James.Cowgill@imgtec.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Alex Smith <alex.smith@imgtec.com> Cc: Adam Buchbinder <adam.buchbinder@gmail.com> Cc: Qais Yousef <qais.yousef@imgtec.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Mikko Rapeli <mikko.rapeli@iki.fi> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Brian Norris <computersforpeace@gmail.com> Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Cc: "Luis R. Rodriguez" <mcgrof@do-not-panic.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Roland McGrath <roland@hack.frob.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Kalle Valo <kvalo@qca.qualcomm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Tony Wu <tung7970@gmail.com> Cc: Huaitong Han <huaitong.han@intel.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: Jason Cooper <jason@lakedaemon.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andrea Gelmini <andrea.gelmini@gelma.net> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Rabin Vincent <rabin@rab.in> Cc: "Maciej W. Rozycki" <macro@imgtec.com> Cc: David Daney <david.daney@cavium.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 03:45:50 +07:00
if (!IS_ENABLED(CONFIG_EVA))
return false;
return segment_eq(get_fs(), get_ds());
}
/*
* 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.
*/
#define __access_mask get_fs().seg
#define __access_ok(addr, size, mask) \
({ \
unsigned long __addr = (unsigned long) (addr); \
unsigned long __size = size; \
unsigned long __mask = mask; \
unsigned long __ok; \
\
__chk_user_ptr(addr); \
__ok = (signed long)(__mask & (__addr | (__addr + __size) | \
__ua_size(__size))); \
__ok == 0; \
})
#define access_ok(type, addr, size) \
likely(__access_ok((addr), (size), __access_mask))
/*
* 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);
/*
* ul{b,h,w} are macros and there are no equivalent macros for EVA.
* EVA unaligned access is handled in the ADE exception handler.
*/
#ifndef CONFIG_EVA
/*
* put_user_unaligned: - 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_unaligned(x,ptr) \
__put_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
/*
* get_user_unaligned: - 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_unaligned(x,ptr) \
__get_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
/*
* __put_user_unaligned: - 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_unaligned(x,ptr) \
__put_user_unaligned_nocheck((x),(ptr),sizeof(*(ptr)))
/*
* __get_user_unaligned: - 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_unaligned(x,ptr) \
__get_user_unaligned_nocheck((x),(ptr),sizeof(*(ptr)))
/*
* Yuck. We need two variants, one for 64bit operation and one
* for 32 bit mode and old iron.
*/
#ifdef CONFIG_32BIT
#define __GET_USER_UNALIGNED_DW(val, ptr) \
__get_user_unaligned_asm_ll32(val, ptr)
#endif
#ifdef CONFIG_64BIT
#define __GET_USER_UNALIGNED_DW(val, ptr) \
__get_user_unaligned_asm(val, "uld", ptr)
#endif
extern void __get_user_unaligned_unknown(void);
#define __get_user_unaligned_common(val, size, ptr) \
do { \
switch (size) { \
case 1: __get_data_asm(val, "lb", ptr); break; \
case 2: __get_data_unaligned_asm(val, "ulh", ptr); break; \
case 4: __get_data_unaligned_asm(val, "ulw", ptr); break; \
case 8: __GET_USER_UNALIGNED_DW(val, ptr); break; \
default: __get_user_unaligned_unknown(); break; \
} \
} while (0)
#define __get_user_unaligned_nocheck(x,ptr,size) \
({ \
int __gu_err; \
\
__get_user_unaligned_common((x), size, ptr); \
__gu_err; \
})
#define __get_user_unaligned_check(x,ptr,size) \
({ \
int __gu_err = -EFAULT; \
const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
\
if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) \
__get_user_unaligned_common((x), size, __gu_ptr); \
\
__gu_err; \
})
#define __get_data_unaligned_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" \
" "__UA_ADDR "\t1b + 4, 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_user_unaligned_asm_ll32(val, addr) \
{ \
unsigned long long __gu_tmp; \
\
__asm__ __volatile__( \
"1: ulw %1, (%3) \n" \
"2: ulw %D1, 4(%3) \n" \
" move %0, $0 \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 " 1b + 4, 4b \n" \
" " __UA_ADDR " 2b, 4b \n" \
" " __UA_ADDR " 2b + 4, 4b \n" \
" .previous \n" \
: "=r" (__gu_err), "=&r" (__gu_tmp) \
: "0" (0), "r" (addr), "i" (-EFAULT)); \
(val) = (__typeof__(*(addr))) __gu_tmp; \
}
/*
* Yuck. We need two variants, one for 64bit operation and one
* for 32 bit mode and old iron.
*/
#ifdef CONFIG_32BIT
#define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm_ll32(ptr)
#endif
#ifdef CONFIG_64BIT
#define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm("usd", ptr)
#endif
#define __put_user_unaligned_common(ptr, size) \
do { \
switch (size) { \
case 1: __put_data_asm("sb", ptr); break; \
case 2: __put_user_unaligned_asm("ush", ptr); break; \
case 4: __put_user_unaligned_asm("usw", ptr); break; \
case 8: __PUT_USER_UNALIGNED_DW(ptr); break; \
default: __put_user_unaligned_unknown(); break; \
} while (0)
#define __put_user_unaligned_nocheck(x,ptr,size) \
({ \
__typeof__(*(ptr)) __pu_val; \
int __pu_err = 0; \
\
__pu_val = (x); \
__put_user_unaligned_common(ptr, size); \
__pu_err; \
})
#define __put_user_unaligned_check(x,ptr,size) \
({ \
__typeof__(*(ptr)) __user *__pu_addr = (ptr); \
__typeof__(*(ptr)) __pu_val = (x); \
int __pu_err = -EFAULT; \
\
if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) \
__put_user_unaligned_common(__pu_addr, size); \
\
__pu_err; \
})
#define __put_user_unaligned_asm(insn, ptr) \
{ \
__asm__ __volatile__( \
"1: " insn " %z2, %3 # __put_user_unaligned_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_user_unaligned_asm_ll32(ptr) \
{ \
__asm__ __volatile__( \
"1: sw %2, (%3) # __put_user_unaligned_asm_ll32 \n" \
"2: sw %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 " 1b + 4, 4b \n" \
" " __UA_ADDR " 2b, 4b \n" \
" " __UA_ADDR " 2b + 4, 4b \n" \
" .previous" \
: "=r" (__pu_err) \
: "0" (0), "r" (__pu_val), "r" (ptr), \
"i" (-EFAULT)); \
}
extern void __put_user_unaligned_unknown(void);
#endif
/*
* 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))
[MIPS] R4000/R4400 daddiu erratum workaround This complements the generic R4000/R4400 errata workaround code and adds bits for the daddiu problem. In most places it just modifies handwritten assembly code so that the assembler is allowed to use a temporary register as daddiu may now be treated as a macro that expands to a sequence of li and daddu. It is the AT register or, where AT is unavailable or used explicitly for another purpose, an explicitly-named register is selected, using the .set at=<reg> feature added recently to gas. This feature is only used if CONFIG_CPU_DADDI_WORKAROUNDS has been set, so if the workaround remains disabled, the required version of binutils stays unchanged. Similarly, daddiu instructions put in branch delay slots in noreorder fragments are now taken out of them and the assembler is allowed to reorder them itself as possible (which it does making the whole idea of scheduling them into delay slots manually questionable). Also in the very few places where such a simple conversion was not possible, a handcoded longer sequence is implemented. Other than that there are changes to code responsible for building the TLB fault and page clear/copy handlers to avoid daddiu as appropriate. These are only effective if the erratum is verified to be present at the run time. Finally there is a trivial update to __delay(), because it uses daddiu in a branch delay slot. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-23 18:43:25 +07:00
#define DADDI_SCRATCH "$3"
#else
#define DADDI_SCRATCH "$0"
[MIPS] R4000/R4400 daddiu erratum workaround This complements the generic R4000/R4400 errata workaround code and adds bits for the daddiu problem. In most places it just modifies handwritten assembly code so that the assembler is allowed to use a temporary register as daddiu may now be treated as a macro that expands to a sequence of li and daddu. It is the AT register or, where AT is unavailable or used explicitly for another purpose, an explicitly-named register is selected, using the .set at=<reg> feature added recently to gas. This feature is only used if CONFIG_CPU_DADDI_WORKAROUNDS has been set, so if the workaround remains disabled, the required version of binutils stays unchanged. Similarly, daddiu instructions put in branch delay slots in noreorder fragments are now taken out of them and the assembler is allowed to reorder them itself as possible (which it does making the whole idea of scheduling them into delay slots manually questionable). Also in the very few places where such a simple conversion was not possible, a handcoded longer sequence is implemented. Other than that there are changes to code responsible for building the TLB fault and page clear/copy handlers to avoid daddiu as appropriate. These are only effective if the erratum is verified to be present at the run time. Finally there is a trivial update to __delay(), because it uses daddiu in a branch delay slot. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-23 18:43:25 +07:00
#endif
extern size_t __copy_user(void *__to, const void *__from, size_t __n);
#ifndef CONFIG_EVA
#define __invoke_copy_to_user(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(__copy_user) \
: "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
: \
: "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
[MIPS] R4000/R4400 daddiu erratum workaround This complements the generic R4000/R4400 errata workaround code and adds bits for the daddiu problem. In most places it just modifies handwritten assembly code so that the assembler is allowed to use a temporary register as daddiu may now be treated as a macro that expands to a sequence of li and daddu. It is the AT register or, where AT is unavailable or used explicitly for another purpose, an explicitly-named register is selected, using the .set at=<reg> feature added recently to gas. This feature is only used if CONFIG_CPU_DADDI_WORKAROUNDS has been set, so if the workaround remains disabled, the required version of binutils stays unchanged. Similarly, daddiu instructions put in branch delay slots in noreorder fragments are now taken out of them and the assembler is allowed to reorder them itself as possible (which it does making the whole idea of scheduling them into delay slots manually questionable). Also in the very few places where such a simple conversion was not possible, a handcoded longer sequence is implemented. Other than that there are changes to code responsible for building the TLB fault and page clear/copy handlers to avoid daddiu as appropriate. These are only effective if the erratum is verified to be present at the run time. Finally there is a trivial update to __delay(), because it uses daddiu in a branch delay slot. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-23 18:43:25 +07:00
DADDI_SCRATCH, "memory"); \
__cu_len_r; \
})
#define __invoke_copy_to_kernel(to, from, n) \
__invoke_copy_to_user(to, from, n)
#endif
/*
* __copy_to_user: - Copy a block of data into user space, with less checking.
* @to: Destination address, in user space.
* @from: Source address, in kernel space.
* @n: Number of bytes to copy.
*
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Copy data from kernel space to user space. Caller must check
* the specified block with access_ok() before calling this function.
*
* Returns number of bytes that could not be copied.
* On success, this will be zero.
*/
#define __copy_to_user(to, from, n) \
({ \
void __user *__cu_to; \
const void *__cu_from; \
long __cu_len; \
\
__cu_to = (to); \
__cu_from = (from); \
__cu_len = (n); \
\
check_object_size(__cu_from, __cu_len, true); \
might_fault(); \
\
if (eva_kernel_access()) \
__cu_len = __invoke_copy_to_kernel(__cu_to, __cu_from, \
__cu_len); \
else \
__cu_len = __invoke_copy_to_user(__cu_to, __cu_from, \
__cu_len); \
__cu_len; \
})
extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
#define __copy_to_user_inatomic(to, from, n) \
({ \
void __user *__cu_to; \
const void *__cu_from; \
long __cu_len; \
\
__cu_to = (to); \
__cu_from = (from); \
__cu_len = (n); \
\
check_object_size(__cu_from, __cu_len, true); \
\
if (eva_kernel_access()) \
__cu_len = __invoke_copy_to_kernel(__cu_to, __cu_from, \
__cu_len); \
else \
__cu_len = __invoke_copy_to_user(__cu_to, __cu_from, \
__cu_len); \
__cu_len; \
})
#define __copy_from_user_inatomic(to, from, n) \
({ \
void *__cu_to; \
const void __user *__cu_from; \
long __cu_len; \
\
__cu_to = (to); \
__cu_from = (from); \
__cu_len = (n); \
\
check_object_size(__cu_to, __cu_len, false); \
\
if (eva_kernel_access()) \
__cu_len = __invoke_copy_from_kernel_inatomic(__cu_to, \
__cu_from,\
__cu_len);\
else \
__cu_len = __invoke_copy_from_user_inatomic(__cu_to, \
__cu_from, \
__cu_len); \
__cu_len; \
})
/*
* copy_to_user: - Copy a block of data into user space.
* @to: Destination address, in user space.
* @from: Source address, in kernel space.
* @n: Number of bytes to copy.
*
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Copy data from kernel space to user space.
*
* Returns number of bytes that could not be copied.
* On success, this will be zero.
*/
#define copy_to_user(to, from, n) \
({ \
void __user *__cu_to; \
const void *__cu_from; \
long __cu_len; \
\
__cu_to = (to); \
__cu_from = (from); \
__cu_len = (n); \
\
check_object_size(__cu_from, __cu_len, true); \
\
if (eva_kernel_access()) { \
__cu_len = __invoke_copy_to_kernel(__cu_to, \
__cu_from, \
__cu_len); \
} else { \
if (access_ok(VERIFY_WRITE, __cu_to, __cu_len)) { \
might_fault(); \
__cu_len = __invoke_copy_to_user(__cu_to, \
__cu_from, \
__cu_len); \
} \
} \
__cu_len; \
})
#ifndef CONFIG_EVA
#define __invoke_copy_from_user(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(__copy_user) \
".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", \
[MIPS] R4000/R4400 daddiu erratum workaround This complements the generic R4000/R4400 errata workaround code and adds bits for the daddiu problem. In most places it just modifies handwritten assembly code so that the assembler is allowed to use a temporary register as daddiu may now be treated as a macro that expands to a sequence of li and daddu. It is the AT register or, where AT is unavailable or used explicitly for another purpose, an explicitly-named register is selected, using the .set at=<reg> feature added recently to gas. This feature is only used if CONFIG_CPU_DADDI_WORKAROUNDS has been set, so if the workaround remains disabled, the required version of binutils stays unchanged. Similarly, daddiu instructions put in branch delay slots in noreorder fragments are now taken out of them and the assembler is allowed to reorder them itself as possible (which it does making the whole idea of scheduling them into delay slots manually questionable). Also in the very few places where such a simple conversion was not possible, a handcoded longer sequence is implemented. Other than that there are changes to code responsible for building the TLB fault and page clear/copy handlers to avoid daddiu as appropriate. These are only effective if the erratum is verified to be present at the run time. Finally there is a trivial update to __delay(), because it uses daddiu in a branch delay slot. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-23 18:43:25 +07:00
DADDI_SCRATCH, "memory"); \
__cu_len_r; \
})
#define __invoke_copy_from_kernel(to, from, n) \
__invoke_copy_from_user(to, from, n)
/* For userland <-> userland operations */
#define ___invoke_copy_in_user(to, from, n) \
__invoke_copy_from_user(to, from, n)
/* For kernel <-> kernel operations */
#define ___invoke_copy_in_kernel(to, from, n) \
__invoke_copy_from_user(to, from, n)
#define __invoke_copy_from_user_inatomic(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(__copy_user_inatomic) \
".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", \
[MIPS] R4000/R4400 daddiu erratum workaround This complements the generic R4000/R4400 errata workaround code and adds bits for the daddiu problem. In most places it just modifies handwritten assembly code so that the assembler is allowed to use a temporary register as daddiu may now be treated as a macro that expands to a sequence of li and daddu. It is the AT register or, where AT is unavailable or used explicitly for another purpose, an explicitly-named register is selected, using the .set at=<reg> feature added recently to gas. This feature is only used if CONFIG_CPU_DADDI_WORKAROUNDS has been set, so if the workaround remains disabled, the required version of binutils stays unchanged. Similarly, daddiu instructions put in branch delay slots in noreorder fragments are now taken out of them and the assembler is allowed to reorder them itself as possible (which it does making the whole idea of scheduling them into delay slots manually questionable). Also in the very few places where such a simple conversion was not possible, a handcoded longer sequence is implemented. Other than that there are changes to code responsible for building the TLB fault and page clear/copy handlers to avoid daddiu as appropriate. These are only effective if the erratum is verified to be present at the run time. Finally there is a trivial update to __delay(), because it uses daddiu in a branch delay slot. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-23 18:43:25 +07:00
DADDI_SCRATCH, "memory"); \
__cu_len_r; \
})
#define __invoke_copy_from_kernel_inatomic(to, from, n) \
__invoke_copy_from_user_inatomic(to, from, n) \
#else
/* EVA specific functions */
extern size_t __copy_user_inatomic_eva(void *__to, const void *__from,
size_t __n);
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);
#define __invoke_copy_from_user_eva_generic(to, from, n, func_ptr) \
({ \
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_ptr) \
".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_user_eva_generic(to, from, n, func_ptr) \
({ \
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__( \
__MODULE_JAL(func_ptr) \
: "+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; \
})
/*
* 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_user_eva_generic(to, from, n, __copy_from_user_eva)
#define __invoke_copy_from_user_inatomic(to, from, n) \
__invoke_copy_from_user_eva_generic(to, from, n, \
__copy_user_inatomic_eva)
#define __invoke_copy_to_user(to, from, n) \
__invoke_copy_to_user_eva_generic(to, from, n, __copy_to_user_eva)
#define ___invoke_copy_in_user(to, from, n) \
__invoke_copy_from_user_eva_generic(to, from, n, __copy_in_user_eva)
/*
* Source or destination address in the kernel. We are not going through
* the TLB
*/
#define __invoke_copy_from_kernel(to, from, n) \
__invoke_copy_from_user_eva_generic(to, from, n, __copy_user)
#define __invoke_copy_from_kernel_inatomic(to, from, n) \
__invoke_copy_from_user_eva_generic(to, from, n, __copy_user_inatomic)
#define __invoke_copy_to_kernel(to, from, n) \
__invoke_copy_to_user_eva_generic(to, from, n, __copy_user)
#define ___invoke_copy_in_kernel(to, from, n) \
__invoke_copy_from_user_eva_generic(to, from, n, __copy_user)
#endif /* CONFIG_EVA */
/*
* __copy_from_user: - Copy a block of data from user space, with less checking.
* @to: Destination address, in kernel space.
* @from: Source address, in user space.
* @n: Number of bytes to copy.
*
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Copy data from user space to kernel space. Caller must check
* the specified block with access_ok() before calling this function.
*
* Returns number of bytes that could not be copied.
* On success, this will be zero.
*
* If some data could not be copied, this function will pad the copied
* data to the requested size using zero bytes.
*/
#define __copy_from_user(to, from, n) \
({ \
void *__cu_to; \
const void __user *__cu_from; \
long __cu_len; \
\
__cu_to = (to); \
__cu_from = (from); \
__cu_len = (n); \
\
check_object_size(__cu_to, __cu_len, false); \
\
MIPS: uaccess: Take EVA into account in __copy_from_user() When EVA is in use, __copy_from_user() was unconditionally using the EVA instructions to read the user address space, however this can also be used for kernel access. If the address isn't a valid user address it will cause an address error or TLB exception, and if it is then user memory may be read instead of kernel memory. For example in the following stack trace from Linux v3.10 (changes since then will prevent this particular one still happening) kernel_sendmsg() set the user address limit to KERNEL_DS, and tcp_sendmsg() goes on to use __copy_from_user() with a kernel address in KSeg0. [<8002d434>] __copy_fromuser_common+0x10c/0x254 [<805710e0>] tcp_sendmsg+0x5f4/0xf00 [<804e8e3c>] sock_sendmsg+0x78/0xa0 [<804e8f28>] kernel_sendmsg+0x24/0x38 [<804ee0f8>] sock_no_sendpage+0x70/0x7c [<8017c820>] pipe_to_sendpage+0x80/0x98 [<8017c6b0>] splice_from_pipe_feed+0xa8/0x198 [<8017cc54>] __splice_from_pipe+0x4c/0x8c [<8017e844>] splice_from_pipe+0x58/0x78 [<8017e884>] generic_splice_sendpage+0x20/0x2c [<8017d690>] do_splice_from+0xb4/0x110 [<8017d710>] direct_splice_actor+0x24/0x30 [<8017d394>] splice_direct_to_actor+0xd8/0x208 [<8017d51c>] do_splice_direct+0x58/0x7c [<8014eaf4>] do_sendfile+0x1dc/0x39c [<8014f82c>] SyS_sendfile+0x90/0xf8 Add the eva_kernel_access() check in __copy_from_user() like the one in copy_from_user(). Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Markos Chandras <markos.chandras@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/10843/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-08-05 22:41:38 +07:00
if (eva_kernel_access()) { \
__cu_len = __invoke_copy_from_kernel(__cu_to, \
__cu_from, \
__cu_len); \
} else { \
might_fault(); \
__cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \
__cu_len); \
} \
__cu_len; \
})
/*
* copy_from_user: - Copy a block of data from user space.
* @to: Destination address, in kernel space.
* @from: Source address, in user space.
* @n: Number of bytes to copy.
*
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Copy data from user space to kernel space.
*
* Returns number of bytes that could not be copied.
* On success, this will be zero.
*
* If some data could not be copied, this function will pad the copied
* data to the requested size using zero bytes.
*/
#define copy_from_user(to, from, n) \
({ \
void *__cu_to; \
const void __user *__cu_from; \
long __cu_len; \
\
__cu_to = (to); \
__cu_from = (from); \
__cu_len = (n); \
\
check_object_size(__cu_to, __cu_len, false); \
\
if (eva_kernel_access()) { \
__cu_len = __invoke_copy_from_kernel(__cu_to, \
__cu_from, \
__cu_len); \
} else { \
if (access_ok(VERIFY_READ, __cu_from, __cu_len)) { \
might_fault(); \
__cu_len = __invoke_copy_from_user(__cu_to, \
__cu_from, \
__cu_len); \
} else { \
memset(__cu_to, 0, __cu_len); \
} \
} \
__cu_len; \
})
#define __copy_in_user(to, from, n) \
({ \
void __user *__cu_to; \
const void __user *__cu_from; \
long __cu_len; \
\
__cu_to = (to); \
__cu_from = (from); \
__cu_len = (n); \
if (eva_kernel_access()) { \
__cu_len = ___invoke_copy_in_kernel(__cu_to, __cu_from, \
__cu_len); \
} else { \
might_fault(); \
__cu_len = ___invoke_copy_in_user(__cu_to, __cu_from, \
__cu_len); \
} \
__cu_len; \
})
#define copy_in_user(to, from, n) \
({ \
void __user *__cu_to; \
const void __user *__cu_from; \
long __cu_len; \
\
__cu_to = (to); \
__cu_from = (from); \
__cu_len = (n); \
if (eva_kernel_access()) { \
__cu_len = ___invoke_copy_in_kernel(__cu_to,__cu_from, \
__cu_len); \
} else { \
if (likely(access_ok(VERIFY_READ, __cu_from, __cu_len) &&\
access_ok(VERIFY_WRITE, __cu_to, __cu_len))) {\
might_fault(); \
__cu_len = ___invoke_copy_in_user(__cu_to, \
__cu_from, \
__cu_len); \
} \
} \
__cu_len; \
})
/*
* __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;
}
#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; \
})
/*
* __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
* @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.
* Caller must check the specified block with access_ok() before calling
* this function.
*
* 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_nocheck_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_nocheck_asm)
"move\t%0, $2"
: "=r" (res)
: "r" (__to), "r" (__from), "r" (__len)
: "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
}
return res;
}
/*
* 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;
}
/*
* strlen_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 there is a limit on the length of a valid string, you may wish to
* consider using strnlen_user() instead.
*/
static inline long strlen_user(const char __user *s)
{
long res;
if (eva_kernel_access()) {
__asm__ __volatile__(
"move\t$4, %1\n\t"
__MODULE_JAL(__strlen_kernel_asm)
"move\t%0, $2"
: "=r" (res)
: "r" (s)
: "$2", "$4", __UA_t0, "$31");
} else {
might_fault();
__asm__ __volatile__(
"move\t$4, %1\n\t"
__MODULE_JAL(__strlen_user_asm)
"move\t%0, $2"
: "=r" (res)
: "r" (s)
: "$2", "$4", __UA_t0, "$31");
}
return res;
}
/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
static inline long __strnlen_user(const char __user *s, long n)
{
long res;
if (eva_kernel_access()) {
__asm__ __volatile__(
"move\t$4, %1\n\t"
"move\t$5, %2\n\t"
__MODULE_JAL(__strnlen_kernel_nocheck_asm)
"move\t%0, $2"
: "=r" (res)
: "r" (s), "r" (n)
: "$2", "$4", "$5", __UA_t0, "$31");
} else {
might_fault();
__asm__ __volatile__(
"move\t$4, %1\n\t"
"move\t$5, %2\n\t"
__MODULE_JAL(__strnlen_user_nocheck_asm)
"move\t%0, $2"
: "=r" (res)
: "r" (s), "r" (n)
: "$2", "$4", "$5", __UA_t0, "$31");
}
return res;
}
/*
* 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;
}
#endif /* _ASM_UACCESS_H */