1de9e46c21
Problem happens when len in strncpy_from_user is setup and passing string has len-1 chars + \0 terminated character. In this case was returned incorrect length of the string. It should always retunrs the length of the string (not including the trailing NULL). Signed-off-by: Michal Simek <michal.simek@xilinx.com>
267 lines
5.2 KiB
ArmAsm
267 lines
5.2 KiB
ArmAsm
/*
|
|
* Copyright (C) 2009 Michal Simek <monstr@monstr.eu>
|
|
* Copyright (C) 2009 PetaLogix
|
|
* Copyright (C) 2007 LynuxWorks, Inc.
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include <linux/errno.h>
|
|
#include <linux/linkage.h>
|
|
#include <asm/page.h>
|
|
|
|
/*
|
|
* int __strncpy_user(char *to, char *from, int len);
|
|
*
|
|
* Returns:
|
|
* -EFAULT for an exception
|
|
* len if we hit the buffer limit
|
|
* bytes copied
|
|
*/
|
|
|
|
.text
|
|
.globl __strncpy_user;
|
|
.type __strncpy_user, @function
|
|
.align 4;
|
|
__strncpy_user:
|
|
|
|
/*
|
|
* r5 - to
|
|
* r6 - from
|
|
* r7 - len
|
|
* r3 - temp count
|
|
* r4 - temp val
|
|
*/
|
|
beqid r7,3f
|
|
addik r3,r7,0 /* temp_count = len */
|
|
1:
|
|
lbu r4,r6,r0
|
|
beqid r4,2f
|
|
sb r4,r5,r0
|
|
|
|
addik r5,r5,1
|
|
addik r6,r6,1 /* delay slot */
|
|
|
|
addik r3,r3,-1
|
|
bnei r3,1b /* break on len */
|
|
2:
|
|
rsubk r3,r3,r7 /* temp_count = len - temp_count */
|
|
3:
|
|
rtsd r15,8
|
|
nop
|
|
.size __strncpy_user, . - __strncpy_user
|
|
|
|
.section .fixup, "ax"
|
|
.align 2
|
|
4:
|
|
brid 3b
|
|
addik r3,r0, -EFAULT
|
|
|
|
.section __ex_table, "a"
|
|
.word 1b,4b
|
|
|
|
/*
|
|
* int __strnlen_user(char __user *str, int maxlen);
|
|
*
|
|
* Returns:
|
|
* 0 on error
|
|
* maxlen + 1 if no NUL byte found within maxlen bytes
|
|
* size of the string (including NUL byte)
|
|
*/
|
|
|
|
.text
|
|
.globl __strnlen_user;
|
|
.type __strnlen_user, @function
|
|
.align 4;
|
|
__strnlen_user:
|
|
beqid r6,3f
|
|
addik r3,r6,0
|
|
1:
|
|
lbu r4,r5,r0
|
|
beqid r4,2f /* break on NUL */
|
|
addik r3,r3,-1 /* delay slot */
|
|
|
|
bneid r3,1b
|
|
addik r5,r5,1 /* delay slot */
|
|
|
|
addik r3,r3,-1 /* for break on len */
|
|
2:
|
|
rsubk r3,r3,r6
|
|
3:
|
|
rtsd r15,8
|
|
nop
|
|
.size __strnlen_user, . - __strnlen_user
|
|
|
|
.section .fixup,"ax"
|
|
4:
|
|
brid 3b
|
|
addk r3,r0,r0
|
|
|
|
.section __ex_table,"a"
|
|
.word 1b,4b
|
|
|
|
/* Loop unrolling for __copy_tofrom_user */
|
|
#define COPY(offset) \
|
|
1: lwi r4 , r6, 0x0000 + offset; \
|
|
2: lwi r19, r6, 0x0004 + offset; \
|
|
3: lwi r20, r6, 0x0008 + offset; \
|
|
4: lwi r21, r6, 0x000C + offset; \
|
|
5: lwi r22, r6, 0x0010 + offset; \
|
|
6: lwi r23, r6, 0x0014 + offset; \
|
|
7: lwi r24, r6, 0x0018 + offset; \
|
|
8: lwi r25, r6, 0x001C + offset; \
|
|
9: swi r4 , r5, 0x0000 + offset; \
|
|
10: swi r19, r5, 0x0004 + offset; \
|
|
11: swi r20, r5, 0x0008 + offset; \
|
|
12: swi r21, r5, 0x000C + offset; \
|
|
13: swi r22, r5, 0x0010 + offset; \
|
|
14: swi r23, r5, 0x0014 + offset; \
|
|
15: swi r24, r5, 0x0018 + offset; \
|
|
16: swi r25, r5, 0x001C + offset; \
|
|
.section __ex_table,"a"; \
|
|
.word 1b, 33f; \
|
|
.word 2b, 33f; \
|
|
.word 3b, 33f; \
|
|
.word 4b, 33f; \
|
|
.word 5b, 33f; \
|
|
.word 6b, 33f; \
|
|
.word 7b, 33f; \
|
|
.word 8b, 33f; \
|
|
.word 9b, 33f; \
|
|
.word 10b, 33f; \
|
|
.word 11b, 33f; \
|
|
.word 12b, 33f; \
|
|
.word 13b, 33f; \
|
|
.word 14b, 33f; \
|
|
.word 15b, 33f; \
|
|
.word 16b, 33f; \
|
|
.text
|
|
|
|
#define COPY_80(offset) \
|
|
COPY(0x00 + offset);\
|
|
COPY(0x20 + offset);\
|
|
COPY(0x40 + offset);\
|
|
COPY(0x60 + offset);
|
|
|
|
/*
|
|
* int __copy_tofrom_user(char *to, char *from, int len)
|
|
* Return:
|
|
* 0 on success
|
|
* number of not copied bytes on error
|
|
*/
|
|
.text
|
|
.globl __copy_tofrom_user;
|
|
.type __copy_tofrom_user, @function
|
|
.align 4;
|
|
__copy_tofrom_user:
|
|
/*
|
|
* r5 - to
|
|
* r6 - from
|
|
* r7, r3 - count
|
|
* r4 - tempval
|
|
*/
|
|
beqid r7, 0f /* zero size is not likely */
|
|
or r3, r5, r6 /* find if is any to/from unaligned */
|
|
or r3, r3, r7 /* find if count is unaligned */
|
|
andi r3, r3, 0x3 /* mask last 3 bits */
|
|
bneid r3, bu1 /* if r3 is not zero then byte copying */
|
|
or r3, r0, r0
|
|
|
|
rsubi r3, r7, PAGE_SIZE /* detect PAGE_SIZE */
|
|
beqid r3, page;
|
|
or r3, r0, r0
|
|
|
|
w1: lw r4, r6, r3 /* at least one 4 byte copy */
|
|
w2: sw r4, r5, r3
|
|
addik r7, r7, -4
|
|
bneid r7, w1
|
|
addik r3, r3, 4
|
|
addik r3, r7, 0
|
|
rtsd r15, 8
|
|
nop
|
|
|
|
.section __ex_table,"a"
|
|
.word w1, 0f;
|
|
.word w2, 0f;
|
|
.text
|
|
|
|
.align 4 /* Alignment is important to keep icache happy */
|
|
page: /* Create room on stack and save registers for storign values */
|
|
addik r1, r1, -40
|
|
swi r5, r1, 0
|
|
swi r6, r1, 4
|
|
swi r7, r1, 8
|
|
swi r19, r1, 12
|
|
swi r20, r1, 16
|
|
swi r21, r1, 20
|
|
swi r22, r1, 24
|
|
swi r23, r1, 28
|
|
swi r24, r1, 32
|
|
swi r25, r1, 36
|
|
loop: /* r4, r19, r20, r21, r22, r23, r24, r25 are used for storing values */
|
|
/* Loop unrolling to get performance boost */
|
|
COPY_80(0x000);
|
|
COPY_80(0x080);
|
|
COPY_80(0x100);
|
|
COPY_80(0x180);
|
|
/* copy loop */
|
|
addik r6, r6, 0x200
|
|
addik r7, r7, -0x200
|
|
bneid r7, loop
|
|
addik r5, r5, 0x200
|
|
|
|
/* Restore register content */
|
|
lwi r5, r1, 0
|
|
lwi r6, r1, 4
|
|
lwi r7, r1, 8
|
|
lwi r19, r1, 12
|
|
lwi r20, r1, 16
|
|
lwi r21, r1, 20
|
|
lwi r22, r1, 24
|
|
lwi r23, r1, 28
|
|
lwi r24, r1, 32
|
|
lwi r25, r1, 36
|
|
addik r1, r1, 40
|
|
/* return back */
|
|
addik r3, r0, 0
|
|
rtsd r15, 8
|
|
nop
|
|
|
|
/* Fault case - return temp count */
|
|
33:
|
|
addik r3, r7, 0
|
|
/* Restore register content */
|
|
lwi r5, r1, 0
|
|
lwi r6, r1, 4
|
|
lwi r7, r1, 8
|
|
lwi r19, r1, 12
|
|
lwi r20, r1, 16
|
|
lwi r21, r1, 20
|
|
lwi r22, r1, 24
|
|
lwi r23, r1, 28
|
|
lwi r24, r1, 32
|
|
lwi r25, r1, 36
|
|
addik r1, r1, 40
|
|
/* return back */
|
|
rtsd r15, 8
|
|
nop
|
|
|
|
.align 4 /* Alignment is important to keep icache happy */
|
|
bu1: lbu r4,r6,r3
|
|
bu2: sb r4,r5,r3
|
|
addik r7,r7,-1
|
|
bneid r7,bu1
|
|
addik r3,r3,1 /* delay slot */
|
|
0:
|
|
addik r3,r7,0
|
|
rtsd r15,8
|
|
nop
|
|
.size __copy_tofrom_user, . - __copy_tofrom_user
|
|
|
|
.section __ex_table,"a"
|
|
.word bu1, 0b;
|
|
.word bu2, 0b;
|
|
.text
|