diff options
Diffstat (limited to 'arch/sparc/lib')
| -rw-r--r-- | arch/sparc/lib/Makefile | 2 | ||||
| -rw-r--r-- | arch/sparc/lib/ksyms.c | 3 | ||||
| -rw-r--r-- | arch/sparc/lib/strncpy_from_user_32.S | 47 | ||||
| -rw-r--r-- | arch/sparc/lib/strncpy_from_user_64.S | 133 | ||||
| -rw-r--r-- | arch/sparc/lib/usercopy.c | 132 |
5 files changed, 133 insertions, 184 deletions
diff --git a/arch/sparc/lib/Makefile b/arch/sparc/lib/Makefile index 389628f50a15..943d98dc4cdb 100644 --- a/arch/sparc/lib/Makefile +++ b/arch/sparc/lib/Makefile @@ -10,7 +10,7 @@ lib-y += strlen.o lib-y += checksum_$(BITS).o lib-$(CONFIG_SPARC32) += blockops.o lib-y += memscan_$(BITS).o memcmp.o strncmp_$(BITS).o -lib-y += strncpy_from_user_$(BITS).o strlen_user_$(BITS).o +lib-y += strlen_user_$(BITS).o lib-$(CONFIG_SPARC32) += divdi3.o udivdi3.o lib-$(CONFIG_SPARC32) += copy_user.o locks.o lib-$(CONFIG_SPARC64) += atomic_64.o diff --git a/arch/sparc/lib/ksyms.c b/arch/sparc/lib/ksyms.c index 2dc30875c8bc..6b278abdb63d 100644 --- a/arch/sparc/lib/ksyms.c +++ b/arch/sparc/lib/ksyms.c @@ -33,9 +33,6 @@ EXPORT_SYMBOL(memset); EXPORT_SYMBOL(memmove); EXPORT_SYMBOL(__bzero); -/* Moving data to/from/in userspace. */ -EXPORT_SYMBOL(__strncpy_from_user); - /* Networking helper routines. */ EXPORT_SYMBOL(csum_partial); diff --git a/arch/sparc/lib/strncpy_from_user_32.S b/arch/sparc/lib/strncpy_from_user_32.S deleted file mode 100644 index db0ed2964bdb..000000000000 --- a/arch/sparc/lib/strncpy_from_user_32.S +++ /dev/null @@ -1,47 +0,0 @@ -/* strncpy_from_user.S: Sparc strncpy from userspace. - * - * Copyright(C) 1996 David S. Miller - */ - -#include <linux/linkage.h> -#include <asm/ptrace.h> -#include <asm/errno.h> - - .text - - /* Must return: - * - * -EFAULT for an exception - * count if we hit the buffer limit - * bytes copied if we hit a null byte - */ - -ENTRY(__strncpy_from_user) - /* %o0=dest, %o1=src, %o2=count */ - mov %o2, %o3 -1: - subcc %o2, 1, %o2 - bneg 2f - nop -10: - ldub [%o1], %o4 - add %o0, 1, %o0 - cmp %o4, 0 - add %o1, 1, %o1 - bne 1b - stb %o4, [%o0 - 1] -2: - add %o2, 1, %o0 - retl - sub %o3, %o0, %o0 -ENDPROC(__strncpy_from_user) - - .section .fixup,#alloc,#execinstr - .align 4 -4: - retl - mov -EFAULT, %o0 - - .section __ex_table,#alloc - .align 4 - .word 10b, 4b diff --git a/arch/sparc/lib/strncpy_from_user_64.S b/arch/sparc/lib/strncpy_from_user_64.S deleted file mode 100644 index d1246b713077..000000000000 --- a/arch/sparc/lib/strncpy_from_user_64.S +++ /dev/null @@ -1,133 +0,0 @@ -/* - * strncpy_from_user.S: Sparc64 strncpy from userspace. - * - * Copyright (C) 1997, 1999 Jakub Jelinek (jj@ultra.linux.cz) - */ - -#include <linux/linkage.h> -#include <asm/asi.h> -#include <asm/errno.h> - - .data - .align 8 -0: .xword 0x0101010101010101 - - .text - - /* Must return: - * - * -EFAULT for an exception - * count if we hit the buffer limit - * bytes copied if we hit a null byte - * (without the null byte) - * - * This implementation assumes: - * %o1 is 8 aligned => !(%o2 & 7) - * %o0 is 8 aligned (if not, it will be slooooow, but will work) - * - * This is optimized for the common case: - * in my stats, 90% of src are 8 aligned (even on sparc32) - * and average length is 18 or so. - */ - -ENTRY(__strncpy_from_user) - /* %o0=dest, %o1=src, %o2=count */ - andcc %o1, 7, %g0 ! IEU1 Group - bne,pn %icc, 30f ! CTI - add %o0, %o2, %g3 ! IEU0 -60: ldxa [%o1] %asi, %g1 ! Load Group - brlez,pn %o2, 10f ! CTI - mov %o0, %o3 ! IEU0 -50: sethi %hi(0b), %o4 ! IEU0 Group - ldx [%o4 + %lo(0b)], %o4 ! Load - sllx %o4, 7, %o5 ! IEU1 Group -1: sub %g1, %o4, %g2 ! IEU0 Group - stx %g1, [%o0] ! Store - add %o0, 8, %o0 ! IEU1 - andcc %g2, %o5, %g0 ! IEU1 Group - bne,pn %xcc, 5f ! CTI - add %o1, 8, %o1 ! IEU0 - cmp %o0, %g3 ! IEU1 Group - bl,a,pt %xcc, 1b ! CTI -61: ldxa [%o1] %asi, %g1 ! Load -10: retl ! CTI Group - mov %o2, %o0 ! IEU0 -5: srlx %g2, 32, %g7 ! IEU0 Group - sethi %hi(0xff00), %o4 ! IEU1 - andcc %g7, %o5, %g0 ! IEU1 Group - be,pn %icc, 2f ! CTI - or %o4, %lo(0xff00), %o4 ! IEU0 - srlx %g1, 48, %g7 ! IEU0 Group - andcc %g7, %o4, %g0 ! IEU1 Group - be,pn %icc, 50f ! CTI - andcc %g7, 0xff, %g0 ! IEU1 Group - be,pn %icc, 51f ! CTI - srlx %g1, 32, %g7 ! IEU0 - andcc %g7, %o4, %g0 ! IEU1 Group - be,pn %icc, 52f ! CTI - andcc %g7, 0xff, %g0 ! IEU1 Group - be,pn %icc, 53f ! CTI -2: andcc %g2, %o5, %g0 ! IEU1 Group - be,pn %icc, 2f ! CTI - srl %g1, 16, %g7 ! IEU0 - andcc %g7, %o4, %g0 ! IEU1 Group - be,pn %icc, 54f ! CTI - andcc %g7, 0xff, %g0 ! IEU1 Group - be,pn %icc, 55f ! CTI - andcc %g1, %o4, %g0 ! IEU1 Group - be,pn %icc, 56f ! CTI - andcc %g1, 0xff, %g0 ! IEU1 Group - be,a,pn %icc, 57f ! CTI - sub %o0, %o3, %o0 ! IEU0 -2: cmp %o0, %g3 ! IEU1 Group - bl,a,pt %xcc, 50b ! CTI -62: ldxa [%o1] %asi, %g1 ! Load - retl ! CTI Group - mov %o2, %o0 ! IEU0 -50: sub %o0, %o3, %o0 - retl - sub %o0, 8, %o0 -51: sub %o0, %o3, %o0 - retl - sub %o0, 7, %o0 -52: sub %o0, %o3, %o0 - retl - sub %o0, 6, %o0 -53: sub %o0, %o3, %o0 - retl - sub %o0, 5, %o0 -54: sub %o0, %o3, %o0 - retl - sub %o0, 4, %o0 -55: sub %o0, %o3, %o0 - retl - sub %o0, 3, %o0 -56: sub %o0, %o3, %o0 - retl - sub %o0, 2, %o0 -57: retl - sub %o0, 1, %o0 -30: brlez,pn %o2, 3f - sub %g0, %o2, %o3 - add %o0, %o2, %o0 -63: lduba [%o1] %asi, %o4 -1: add %o1, 1, %o1 - brz,pn %o4, 2f - stb %o4, [%o0 + %o3] - addcc %o3, 1, %o3 - bne,pt %xcc, 1b -64: lduba [%o1] %asi, %o4 -3: retl - mov %o2, %o0 -2: retl - add %o2, %o3, %o0 -ENDPROC(__strncpy_from_user) - - .section __ex_table,"a" - .align 4 - .word 60b, __retl_efault - .word 61b, __retl_efault - .word 62b, __retl_efault - .word 63b, __retl_efault - .word 64b, __retl_efault - .previous diff --git a/arch/sparc/lib/usercopy.c b/arch/sparc/lib/usercopy.c index 14b363fec8a2..851cb75ce189 100644 --- a/arch/sparc/lib/usercopy.c +++ b/arch/sparc/lib/usercopy.c @@ -1,4 +1,6 @@ #include <linux/module.h> +#include <linux/uaccess.h> +#include <linux/errno.h> #include <linux/bug.h> void copy_from_user_overflow(void) @@ -6,3 +8,133 @@ void copy_from_user_overflow(void) WARN(1, "Buffer overflow detected!\n"); } EXPORT_SYMBOL(copy_from_user_overflow); + +#define REPEAT_BYTE(x) ((~0ul / 0xff) * (x)) + +/* Return the high bit set in the first byte that is a zero */ +static inline unsigned long has_zero(unsigned long a) +{ + return ((a - REPEAT_BYTE(0x01)) & ~a) & REPEAT_BYTE(0x80); +} + +static inline long find_zero(unsigned long c) +{ +#ifdef CONFIG_64BIT + if (!(c & 0xff00000000000000UL)) + return 0; + if (!(c & 0x00ff000000000000UL)) + return 1; + if (!(c & 0x0000ff0000000000UL)) + return 2; + if (!(c & 0x000000ff00000000UL)) + return 3; +#define __OFF 4 +#else +#define __OFF 0 +#endif + if (!(c & 0xff000000)) + return __OFF + 0; + if (!(c & 0x00ff0000)) + return __OFF + 1; + if (!(c & 0x0000ff00)) + return __OFF + 2; + return __OFF + 3; +#undef __OFF +} + +/* + * Do a strncpy, return length of string without final '\0'. + * 'count' is the user-supplied count (return 'count' if we + * hit it), 'max' is the address space maximum (and we return + * -EFAULT if we hit it). + */ +static inline long do_strncpy_from_user(char *dst, const char __user *src, long count, unsigned long max) +{ + long res = 0; + + /* + * Truncate 'max' to the user-specified limit, so that + * we only have one limit we need to check in the loop + */ + if (max > count) + max = count; + + if (((long) dst | (long) src) & (sizeof(long) - 1)) + goto byte_at_a_time; + + while (max >= sizeof(unsigned long)) { + unsigned long c; + + /* Fall back to byte-at-a-time if we get a page fault */ + if (unlikely(__get_user(c,(unsigned long __user *)(src+res)))) + break; + *(unsigned long *)(dst+res) = c; + if (has_zero(c)) + return res + find_zero(c); + res += sizeof(unsigned long); + max -= sizeof(unsigned long); + } + +byte_at_a_time: + while (max) { + char c; + + if (unlikely(__get_user(c,src+res))) + return -EFAULT; + dst[res] = c; + if (!c) + return res; + res++; + max--; + } + + /* + * Uhhuh. We hit 'max'. But was that the user-specified maximum + * too? If so, that's ok - we got as much as the user asked for. + */ + if (res >= count) + return res; + + /* + * Nope: we hit the address space limit, and we still had more + * characters the caller would have wanted. That's an EFAULT. + */ + return -EFAULT; +} + +/** + * 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. + */ +long strncpy_from_user(char *dst, const char __user *src, long count) +{ + unsigned long max_addr, src_addr; + + if (unlikely(count <= 0)) + return 0; + + max_addr = ~0UL; + if (likely(segment_eq(get_fs(), USER_DS))) + max_addr = STACK_TOP; + src_addr = (unsigned long)src; + if (likely(src_addr < max_addr)) { + unsigned long max = max_addr - src_addr; + return do_strncpy_from_user(dst, src, count, max); + } + return -EFAULT; +} +EXPORT_SYMBOL(strncpy_from_user); |