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-rw-r--r--arch/x86/lib/csum-wrappers_64.c87
1 files changed, 51 insertions, 36 deletions
diff --git a/arch/x86/lib/csum-wrappers_64.c b/arch/x86/lib/csum-wrappers_64.c
index 95e45dcc5a2..459b58a8a15 100644
--- a/arch/x86/lib/csum-wrappers_64.c
+++ b/arch/x86/lib/csum-wrappers_64.c
@@ -1,9 +1,9 @@
-/* Copyright 2002,2003 Andi Kleen, SuSE Labs.
+/*
+ * Copyright 2002, 2003 Andi Kleen, SuSE Labs.
* Subject to the GNU Public License v.2
*
* Wrappers of assembly checksum functions for x86-64.
*/
-
#include <asm/checksum.h>
#include <linux/module.h>
@@ -24,37 +24,47 @@ csum_partial_copy_from_user(const void __user *src, void *dst,
{
might_sleep();
*errp = 0;
- if (likely(access_ok(VERIFY_READ, src, len))) {
- /* Why 6, not 7? To handle odd addresses aligned we
- would need to do considerable complications to fix the
- checksum which is defined as an 16bit accumulator. The
- fix alignment code is primarily for performance
- compatibility with 32bit and that will handle odd
- addresses slowly too. */
- if (unlikely((unsigned long)src & 6)) {
- while (((unsigned long)src & 6) && len >= 2) {
- __u16 val16;
- *errp = __get_user(val16, (const __u16 __user *)src);
- if (*errp)
- return isum;
- *(__u16 *)dst = val16;
- isum = (__force __wsum)add32_with_carry(
- (__force unsigned)isum, val16);
- src += 2;
- dst += 2;
- len -= 2;
- }
+
+ if (!likely(access_ok(VERIFY_READ, src, len)))
+ goto out_err;
+
+ /*
+ * Why 6, not 7? To handle odd addresses aligned we
+ * would need to do considerable complications to fix the
+ * checksum which is defined as an 16bit accumulator. The
+ * fix alignment code is primarily for performance
+ * compatibility with 32bit and that will handle odd
+ * addresses slowly too.
+ */
+ if (unlikely((unsigned long)src & 6)) {
+ while (((unsigned long)src & 6) && len >= 2) {
+ __u16 val16;
+
+ *errp = __get_user(val16, (const __u16 __user *)src);
+ if (*errp)
+ return isum;
+
+ *(__u16 *)dst = val16;
+ isum = (__force __wsum)add32_with_carry(
+ (__force unsigned)isum, val16);
+ src += 2;
+ dst += 2;
+ len -= 2;
}
- isum = csum_partial_copy_generic((__force const void *)src,
- dst, len, isum, errp, NULL);
- if (likely(*errp == 0))
- return isum;
}
+ isum = csum_partial_copy_generic((__force const void *)src,
+ dst, len, isum, errp, NULL);
+ if (unlikely(*errp))
+ goto out_err;
+
+ return isum;
+
+out_err:
*errp = -EFAULT;
memset(dst, 0, len);
+
return isum;
}
-
EXPORT_SYMBOL(csum_partial_copy_from_user);
/**
@@ -73,6 +83,7 @@ csum_partial_copy_to_user(const void *src, void __user *dst,
int len, __wsum isum, int *errp)
{
might_sleep();
+
if (unlikely(!access_ok(VERIFY_WRITE, dst, len))) {
*errp = -EFAULT;
return 0;
@@ -81,6 +92,7 @@ csum_partial_copy_to_user(const void *src, void __user *dst,
if (unlikely((unsigned long)dst & 6)) {
while (((unsigned long)dst & 6) && len >= 2) {
__u16 val16 = *(__u16 *)src;
+
isum = (__force __wsum)add32_with_carry(
(__force unsigned)isum, val16);
*errp = __put_user(val16, (__u16 __user *)dst);
@@ -93,9 +105,9 @@ csum_partial_copy_to_user(const void *src, void __user *dst,
}
*errp = 0;
- return csum_partial_copy_generic(src, (void __force *)dst, len, isum, NULL, errp);
+ return csum_partial_copy_generic(src, (void __force *)dst,
+ len, isum, NULL, errp);
}
-
EXPORT_SYMBOL(csum_partial_copy_to_user);
/**
@@ -122,14 +134,17 @@ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
rest = (__force __u64)htonl(len) + (__force __u64)htons(proto) +
(__force __u64)sum;
- asm(" addq (%[saddr]),%[sum]\n"
- " adcq 8(%[saddr]),%[sum]\n"
- " adcq (%[daddr]),%[sum]\n"
- " adcq 8(%[daddr]),%[sum]\n"
- " adcq $0,%[sum]\n"
+
+ asm(" addq (%[saddr]),%[sum]\n"
+ " adcq 8(%[saddr]),%[sum]\n"
+ " adcq (%[daddr]),%[sum]\n"
+ " adcq 8(%[daddr]),%[sum]\n"
+ " adcq $0,%[sum]\n"
+
: [sum] "=r" (sum64)
: "[sum]" (rest), [saddr] "r" (saddr), [daddr] "r" (daddr));
- return csum_fold((__force __wsum)add32_with_carry(sum64 & 0xffffffff, sum64>>32));
-}
+ return csum_fold(
+ (__force __wsum)add32_with_carry(sum64 & 0xffffffff, sum64>>32));
+}
EXPORT_SYMBOL(csum_ipv6_magic);