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authorStuart Menefy <stuart.menefy@st.com>2007-11-30 18:16:23 +0900
committerPaul Mundt <lethal@linux-sh.org>2008-01-28 13:18:59 +0900
commit0fb19dcb64ec4bd9934eee26ce66417fe028ffd8 (patch)
treea2bb20e3d3f0703959e800cfcab2ad0eb81bf503
parentfc55888f83c1c0ac09abe4680f9a94fc0662677f (diff)
downloadop-kernel-dev-0fb19dcb64ec4bd9934eee26ce66417fe028ffd8.zip
op-kernel-dev-0fb19dcb64ec4bd9934eee26ce66417fe028ffd8.tar.gz
sh: get_user fixes and nommu consolidation.
When a get_user(to, from++) is called the pointer increment is performed after its first usage, in the specific after the __add_ok invokation. This causes a wrong get_user return value, putting a wrong character in the destination variable. This patch solves the problem using a new temporary pointer. Additionally this reworks the use of the register banks, allowing for consolidation between the MMU and nommu implementations. Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com> Signed-off-by: Giuseppe Condorelli <giuseppe.condorelli@st.com> Signed-off-by: Stuart Menefy <stuart.menefy@st.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
-rw-r--r--include/asm-sh/uaccess_32.h253
1 files changed, 98 insertions, 155 deletions
diff --git a/include/asm-sh/uaccess_32.h b/include/asm-sh/uaccess_32.h
index f18a1a5..59a9f20 100644
--- a/include/asm-sh/uaccess_32.h
+++ b/include/asm-sh/uaccess_32.h
@@ -73,37 +73,24 @@ static inline int __access_ok(unsigned long addr, unsigned long size)
/*
* __access_ok: Check if address with size is OK or not.
*
- * We do three checks:
- * (1) is it user space?
- * (2) addr + size --> carry?
- * (3) addr + size >= 0x80000000 (PAGE_OFFSET)
+ * Uhhuh, this needs 33-bit arithmetic. We have a carry..
*
- * (1) (2) (3) | RESULT
- * 0 0 0 | ok
- * 0 0 1 | ok
- * 0 1 0 | bad
- * 0 1 1 | bad
- * 1 0 0 | ok
- * 1 0 1 | bad
- * 1 1 0 | bad
- * 1 1 1 | bad
+ * sum := addr + size; carry? --> flag = true;
+ * if (sum >= addr_limit) flag = true;
*/
static inline int __access_ok(unsigned long addr, unsigned long size)
{
- unsigned long flag, tmp;
-
- __asm__("stc r7_bank, %0\n\t"
- "mov.l @(8,%0), %0\n\t"
- "clrt\n\t"
- "addc %2, %1\n\t"
- "and %1, %0\n\t"
- "rotcl %0\n\t"
- "rotcl %0\n\t"
- "and #3, %0"
- : "=&z" (flag), "=r" (tmp)
- : "r" (addr), "1" (size)
- : "t");
-
+ unsigned long flag, sum;
+
+ __asm__("clrt\n\t"
+ "addc %3, %1\n\t"
+ "movt %0\n\t"
+ "cmp/hi %4, %1\n\t"
+ "rotcl %0"
+ :"=&r" (flag), "=r" (sum)
+ :"1" (addr), "r" (size),
+ "r" (current_thread_info()->addr_limit.seg)
+ :"t");
return flag == 0;
}
#endif /* CONFIG_MMU */
@@ -165,135 +152,47 @@ do { \
#define __get_user_nocheck(x,ptr,size) \
({ \
long __gu_err, __gu_val; \
- __get_user_size(__gu_val, (ptr), (size), __gu_err); \
+ __typeof__(*(ptr)) *__pu_addr = (ptr); \
+ __get_user_size(__gu_val, (__pu_addr), (size), __gu_err); \
(x) = (__typeof__(*(ptr)))__gu_val; \
__gu_err; \
})
-#ifdef CONFIG_MMU
-#define __get_user_check(x,ptr,size) \
-({ \
- long __gu_err, __gu_val; \
- __chk_user_ptr(ptr); \
- switch (size) { \
- case 1: \
- __get_user_1(__gu_val, (ptr), __gu_err); \
- break; \
- case 2: \
- __get_user_2(__gu_val, (ptr), __gu_err); \
- break; \
- case 4: \
- __get_user_4(__gu_val, (ptr), __gu_err); \
- break; \
- default: \
- __get_user_unknown(); \
- break; \
- } \
- \
- (x) = (__typeof__(*(ptr)))__gu_val; \
- __gu_err; \
-})
-
-#define __get_user_1(x,addr,err) ({ \
-__asm__("stc r7_bank, %1\n\t" \
- "mov.l @(8,%1), %1\n\t" \
- "and %2, %1\n\t" \
- "cmp/pz %1\n\t" \
- "bt/s 1f\n\t" \
- " mov #0, %0\n\t" \
- "0:\n" \
- "mov #-14, %0\n\t" \
- "bra 2f\n\t" \
- " mov #0, %1\n" \
- "1:\n\t" \
- "mov.b @%2, %1\n\t" \
- "extu.b %1, %1\n" \
- "2:\n" \
- ".section __ex_table,\"a\"\n\t" \
- ".long 1b, 0b\n\t" \
- ".previous" \
- : "=&r" (err), "=&r" (x) \
- : "r" (addr) \
- : "t"); \
-})
-
-#define __get_user_2(x,addr,err) ({ \
-__asm__("stc r7_bank, %1\n\t" \
- "mov.l @(8,%1), %1\n\t" \
- "and %2, %1\n\t" \
- "cmp/pz %1\n\t" \
- "bt/s 1f\n\t" \
- " mov #0, %0\n\t" \
- "0:\n" \
- "mov #-14, %0\n\t" \
- "bra 2f\n\t" \
- " mov #0, %1\n" \
- "1:\n\t" \
- "mov.w @%2, %1\n\t" \
- "extu.w %1, %1\n" \
- "2:\n" \
- ".section __ex_table,\"a\"\n\t" \
- ".long 1b, 0b\n\t" \
- ".previous" \
- : "=&r" (err), "=&r" (x) \
- : "r" (addr) \
- : "t"); \
-})
-
-#define __get_user_4(x,addr,err) ({ \
-__asm__("stc r7_bank, %1\n\t" \
- "mov.l @(8,%1), %1\n\t" \
- "and %2, %1\n\t" \
- "cmp/pz %1\n\t" \
- "bt/s 1f\n\t" \
- " mov #0, %0\n\t" \
- "0:\n" \
- "mov #-14, %0\n\t" \
- "bra 2f\n\t" \
- " mov #0, %1\n" \
- "1:\n\t" \
- "mov.l @%2, %1\n\t" \
- "2:\n" \
- ".section __ex_table,\"a\"\n\t" \
- ".long 1b, 0b\n\t" \
- ".previous" \
- : "=&r" (err), "=&r" (x) \
- : "r" (addr) \
- : "t"); \
-})
-#else /* CONFIG_MMU */
#define __get_user_check(x,ptr,size) \
({ \
long __gu_err, __gu_val; \
- if (__access_ok((unsigned long)(ptr), (size))) { \
- __get_user_size(__gu_val, (ptr), (size), __gu_err); \
- (x) = (__typeof__(*(ptr)))__gu_val; \
- } else \
+ __typeof__(*(ptr)) *__pu_addr = (ptr); \
+ __chk_user_ptr(__pu_addr); \
+ if (likely(__addr_ok((unsigned long)(__pu_addr)))) { \
+ __get_user_size(__gu_val, (__pu_addr), (size), __gu_err);\
+ } else { \
__gu_err = -EFAULT; \
+ __gu_val = 0; \
+ } \
+ (x) = (__typeof__(*(ptr)))__gu_val; \
__gu_err; \
})
-#endif
#define __get_user_asm(x, addr, err, insn) \
({ \
__asm__ __volatile__( \
"1:\n\t" \
"mov." insn " %2, %1\n\t" \
- "mov #0, %0\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3:\n\t" \
"mov #0, %1\n\t" \
"mov.l 4f, %0\n\t" \
"jmp @%0\n\t" \
- " mov %3, %0\n" \
+ " mov %3, %0\n\t" \
+ ".balign 4\n" \
"4: .long 2b\n\t" \
".previous\n" \
".section __ex_table,\"a\"\n\t" \
".long 1b, 3b\n\t" \
".previous" \
:"=&r" (err), "=&r" (x) \
- :"m" (__m(addr)), "i" (-EFAULT)); })
+ :"m" (__m(addr)), "i" (-EFAULT), "0" (err)); })
extern void __get_user_unknown(void);
@@ -328,11 +227,13 @@ do { \
#define __put_user_check(x,ptr,size) \
({ \
- long __pu_err = -EFAULT; \
+ long __pu_err; \
__typeof__(*(ptr)) __user *__pu_addr = (ptr); \
\
- if (__access_ok((unsigned long)__pu_addr,size)) \
+ if (likely(__addr_ok((unsigned long)__pu_addr))) \
__put_user_size((x),__pu_addr,(size),__pu_err); \
+ else \
+ __pu_err = -EFAULT; \
__pu_err; \
})
@@ -341,45 +242,43 @@ do { \
__asm__ __volatile__( \
"1:\n\t" \
"mov." insn " %1, %2\n\t" \
- "mov #0, %0\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3:\n\t" \
- "nop\n\t" \
"mov.l 4f, %0\n\t" \
"jmp @%0\n\t" \
- "mov %3, %0\n" \
+ " mov %3, %0\n\t" \
+ ".balign 4\n" \
"4: .long 2b\n\t" \
".previous\n" \
".section __ex_table,\"a\"\n\t" \
".long 1b, 3b\n\t" \
".previous" \
:"=&r" (err) \
- :"r" (x), "m" (__m(addr)), "i" (-EFAULT) \
+ :"r" (x), "m" (__m(addr)), "i" (-EFAULT), "0" (err) \
:"memory"); })
-#if defined(__LITTLE_ENDIAN__)
+#if defined(CONFIG_CPU_LITTLE_ENDIAN)
#define __put_user_u64(val,addr,retval) \
({ \
__asm__ __volatile__( \
"1:\n\t" \
"mov.l %R1,%2\n\t" \
"mov.l %S1,%T2\n\t" \
- "mov #0,%0\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3:\n\t" \
- "nop\n\t" \
"mov.l 4f,%0\n\t" \
"jmp @%0\n\t" \
- " mov %3,%0\n" \
+ " mov %3,%0\n\t" \
+ ".balign 4\n" \
"4: .long 2b\n\t" \
".previous\n" \
".section __ex_table,\"a\"\n\t" \
".long 1b, 3b\n\t" \
".previous" \
: "=r" (retval) \
- : "r" (val), "m" (__m(addr)), "i" (-EFAULT) \
+ : "r" (val), "m" (__m(addr)), "i" (-EFAULT), "0" (retval) \
: "memory"); })
#else
#define __put_user_u64(val,addr,retval) \
@@ -388,21 +287,20 @@ __asm__ __volatile__( \
"1:\n\t" \
"mov.l %S1,%2\n\t" \
"mov.l %R1,%T2\n\t" \
- "mov #0,%0\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3:\n\t" \
- "nop\n\t" \
"mov.l 4f,%0\n\t" \
"jmp @%0\n\t" \
- " mov %3,%0\n" \
+ " mov %3,%0\n\t" \
+ ".balign 4\n" \
"4: .long 2b\n\t" \
".previous\n" \
".section __ex_table,\"a\"\n\t" \
".long 1b, 3b\n\t" \
".previous" \
: "=r" (retval) \
- : "r" (val), "m" (__m(addr)), "i" (-EFAULT) \
+ : "r" (val), "m" (__m(addr)), "i" (-EFAULT), "0" (retval) \
: "memory"); })
#endif
@@ -463,7 +361,7 @@ static __inline__ int
__strncpy_from_user(unsigned long __dest, unsigned long __user __src, int __count)
{
__kernel_size_t res;
- unsigned long __dummy, _d, _s;
+ unsigned long __dummy, _d, _s, _c;
__asm__ __volatile__(
"9:\n"
@@ -472,17 +370,17 @@ __strncpy_from_user(unsigned long __dest, unsigned long __user __src, int __coun
"bt/s 2f\n"
"1:\n"
"mov.b %1, @%3\n\t"
- "dt %7\n\t"
+ "dt %4\n\t"
"bf/s 9b\n\t"
" add #1, %3\n\t"
"2:\n\t"
- "sub %7, %0\n"
+ "sub %4, %0\n"
"3:\n"
".section .fixup,\"ax\"\n"
"4:\n\t"
"mov.l 5f, %1\n\t"
"jmp @%1\n\t"
- " mov %8, %0\n\t"
+ " mov %9, %0\n\t"
".balign 4\n"
"5: .long 3b\n"
".previous\n"
@@ -490,14 +388,32 @@ __strncpy_from_user(unsigned long __dest, unsigned long __user __src, int __coun
" .balign 4\n"
" .long 9b,4b\n"
".previous"
- : "=r" (res), "=&z" (__dummy), "=r" (_s), "=r" (_d)
- : "0" (__count), "2" (__src), "3" (__dest), "r" (__count),
+ : "=r" (res), "=&z" (__dummy), "=r" (_s), "=r" (_d), "=r"(_c)
+ : "0" (__count), "2" (__src), "3" (__dest), "4" (__count),
"i" (-EFAULT)
: "memory", "t");
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.
+ */
#define strncpy_from_user(dest,src,count) ({ \
unsigned long __sfu_src = (unsigned long) (src); \
int __sfu_count = (int) (count); \
@@ -507,7 +423,8 @@ __sfu_res = __strncpy_from_user((unsigned long) (dest), __sfu_src, __sfu_count);
} __sfu_res; })
/*
- * Return the size of a string (including the ending 0!)
+ * Return the size of a string (including the ending 0 even when we have
+ * exceeded the maximum string length).
*/
static __inline__ long __strnlen_user(const char __user *__s, long __n)
{
@@ -515,14 +432,13 @@ static __inline__ long __strnlen_user(const char __user *__s, long __n)
unsigned long __dummy;
__asm__ __volatile__(
- "9:\n"
- "cmp/eq %4, %0\n\t"
- "bt 2f\n"
"1:\t"
"mov.b @(%0,%3), %1\n\t"
+ "cmp/eq %4, %0\n\t"
+ "bt/s 2f\n\t"
+ " add #1, %0\n\t"
"tst %1, %1\n\t"
- "bf/s 9b\n\t"
- " add #1, %0\n"
+ "bf 1b\n\t"
"2:\n"
".section .fixup,\"ax\"\n"
"3:\n\t"
@@ -542,6 +458,19 @@ static __inline__ long __strnlen_user(const char __user *__s, long __n)
return res;
}
+/**
+ * strnlen_user: - Get the size of a string in user space.
+ * @s: The string to measure.
+ * @n: The maximum valid length
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * 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)
{
if (!__addr_ok(s))
@@ -550,6 +479,20 @@ static __inline__ long strnlen_user(const char __user *s, long n)
return __strnlen_user(s, n);
}
+/**
+ * strlen_user: - Get the size of a string in user space.
+ * @str: The string to measure.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * 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.
+ */
#define strlen_user(str) strnlen_user(str, ~0UL >> 1)
/*
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