From 6e41c585e38ff696de3a11509a0ad0a11150b0c3 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Wed, 22 Jul 2020 22:14:36 -0400
Subject: unify generic instances of csum_partial_copy_nocheck()

quite a few architectures have the same csum_partial_copy_nocheck() -
simply memcpy() the data and then return the csum of the copy.

hexagon, parisc, ia64, s390, um: explicitly spelled out that way.

arc, arm64, csky, h8300, m68k/nommu, microblaze, mips/GENERIC_CSUM, nds32,
nios2, openrisc, riscv, unicore32: end up picking the same thing spelled
out in lib/checksum.h (with varying amounts of perversions along the way).

everybody else (alpha, arm, c6x, m68k/mmu, mips/!GENERIC_CSUM, powerpc,
sh, sparc, x86, xtensa) have non-generic variants.  For all except c6x
the declaration is in their asm/checksum.h.  c6x uses the wrapper
from asm-generic/checksum.h that would normally lead to the lib/checksum.h
instance, but in case of c6x we end up using an asm function from arch/c6x
instead.

Screw that mess - have architectures with private instances define
_HAVE_ARCH_CSUM_AND_COPY in their asm/checksum.h and have the default
one right in net/checksum.h conditional on _HAVE_ARCH_CSUM_AND_COPY
*not* defined.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 arch/alpha/include/asm/checksum.h | 1 +
 1 file changed, 1 insertion(+)

(limited to 'arch/alpha')

diff --git a/arch/alpha/include/asm/checksum.h b/arch/alpha/include/asm/checksum.h
index 0eac81624d01..7e8e4fa4362d 100644
--- a/arch/alpha/include/asm/checksum.h
+++ b/arch/alpha/include/asm/checksum.h
@@ -42,6 +42,7 @@ extern __wsum csum_partial(const void *buff, int len, __wsum sum);
  * better 64-bit) boundary
  */
 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
+#define _HAVE_ARCH_CSUM_AND_COPY
 __wsum csum_and_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *errp);
 
 __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
-- 
cgit v1.2.3-59-g8ed1b


From cc44c17baf7f3f833d36b2f2a1edb1cc0b6f2cc4 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Sat, 11 Jul 2020 00:12:07 -0400
Subject: csum_partial_copy_nocheck(): drop the last argument

It's always 0.  Note that we theoretically could use ~0U as well -
result will be the same modulo 0xffff, _if_ the damn thing did the
right thing for any value of initial sum; later we'll make use of
that when convenient.

However, unlike csum_and_copy_..._user(), there are instances that
did not work for arbitrary initial sums; c6x is one such.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 arch/alpha/include/asm/checksum.h    | 2 +-
 arch/alpha/lib/csum_partial_copy.c   | 4 ++--
 arch/arm/include/asm/checksum.h      | 2 +-
 arch/arm/lib/csumpartialcopy.S       | 5 +++--
 arch/c6x/include/asm/checksum.h      | 2 +-
 arch/c6x/lib/csum_64plus.S           | 4 +---
 arch/m68k/include/asm/checksum.h     | 3 +--
 arch/m68k/lib/checksum.c             | 3 ++-
 arch/mips/include/asm/checksum.h     | 7 +++++--
 arch/mips/lib/csum_partial.S         | 4 ++--
 arch/powerpc/include/asm/checksum.h  | 4 ++--
 arch/sh/include/asm/checksum_32.h    | 5 ++---
 arch/sparc/include/asm/checksum_32.h | 4 ++--
 arch/sparc/include/asm/checksum_64.h | 8 ++++++--
 arch/sparc/lib/csum_copy.S           | 2 +-
 arch/x86/include/asm/checksum_32.h   | 5 ++---
 arch/x86/include/asm/checksum_64.h   | 3 +--
 arch/x86/lib/csum-wrappers_64.c      | 4 ++--
 arch/xtensa/include/asm/checksum.h   | 5 ++---
 drivers/net/ethernet/3com/typhoon.c  | 3 +--
 include/net/checksum.h               | 4 ++--
 lib/iov_iter.c                       | 2 +-
 net/core/skbuff.c                    | 4 ++--
 net/ipv4/icmp.c                      | 2 +-
 net/ipv4/ip_output.c                 | 2 +-
 net/ipv4/raw.c                       | 2 +-
 net/ipv6/raw.c                       | 2 +-
 27 files changed, 49 insertions(+), 48 deletions(-)

(limited to 'arch/alpha')

diff --git a/arch/alpha/include/asm/checksum.h b/arch/alpha/include/asm/checksum.h
index 7e8e4fa4362d..84f9faea864a 100644
--- a/arch/alpha/include/asm/checksum.h
+++ b/arch/alpha/include/asm/checksum.h
@@ -45,7 +45,7 @@ extern __wsum csum_partial(const void *buff, int len, __wsum sum);
 #define _HAVE_ARCH_CSUM_AND_COPY
 __wsum csum_and_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *errp);
 
-__wsum csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
+__wsum csum_partial_copy_nocheck(const void *src, void *dst, int len);
 
 
 /*
diff --git a/arch/alpha/lib/csum_partial_copy.c b/arch/alpha/lib/csum_partial_copy.c
index af1dad74e933..f363dc89fcbe 100644
--- a/arch/alpha/lib/csum_partial_copy.c
+++ b/arch/alpha/lib/csum_partial_copy.c
@@ -372,13 +372,13 @@ csum_and_copy_from_user(const void __user *src, void *dst, int len,
 EXPORT_SYMBOL(csum_and_copy_from_user);
 
 __wsum
-csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
+csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
 	__wsum checksum;
 	mm_segment_t oldfs = get_fs();
 	set_fs(KERNEL_DS);
 	checksum = csum_and_copy_from_user((__force const void __user *)src,
-						dst, len, sum, NULL);
+						dst, len, 0, NULL);
 	set_fs(oldfs);
 	return checksum;
 }
diff --git a/arch/arm/include/asm/checksum.h b/arch/arm/include/asm/checksum.h
index 53f769508540..7612b2bd4e9b 100644
--- a/arch/arm/include/asm/checksum.h
+++ b/arch/arm/include/asm/checksum.h
@@ -35,7 +35,7 @@ __wsum csum_partial(const void *buff, int len, __wsum sum);
  */
 
 __wsum
-csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
+csum_partial_copy_nocheck(const void *src, void *dst, int len);
 
 __wsum
 csum_partial_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *err_ptr);
diff --git a/arch/arm/lib/csumpartialcopy.S b/arch/arm/lib/csumpartialcopy.S
index 184d97254a7a..aab914fbc86b 100644
--- a/arch/arm/lib/csumpartialcopy.S
+++ b/arch/arm/lib/csumpartialcopy.S
@@ -9,13 +9,14 @@
 
 		.text
 
-/* Function: __u32 csum_partial_copy_nocheck(const char *src, char *dst, int len, __u32 sum)
- * Params  : r0 = src, r1 = dst, r2 = len, r3 = checksum
+/* Function: __u32 csum_partial_copy_nocheck(const char *src, char *dst, int len)
+ * Params  : r0 = src, r1 = dst, r2 = len
  * Returns : r0 = new checksum
  */
 
 		.macro	save_regs
 		stmfd	sp!, {r1, r4 - r8, lr}
+		mov	r3, #0
 		.endm
 
 		.macro	load_regs
diff --git a/arch/c6x/include/asm/checksum.h b/arch/c6x/include/asm/checksum.h
index fa31bdc186b2..934918def632 100644
--- a/arch/c6x/include/asm/checksum.h
+++ b/arch/c6x/include/asm/checksum.h
@@ -27,7 +27,7 @@ csum_tcpudp_nofold(__be32 saddr, __be32 daddr, __u32 len,
 #define csum_tcpudp_nofold csum_tcpudp_nofold
 
 #define _HAVE_ARCH_CSUM_AND_COPY
-extern __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
+extern __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len);
 
 #include <asm-generic/checksum.h>
 
diff --git a/arch/c6x/lib/csum_64plus.S b/arch/c6x/lib/csum_64plus.S
index 9c07127485d1..57148866d8d3 100644
--- a/arch/c6x/lib/csum_64plus.S
+++ b/arch/c6x/lib/csum_64plus.S
@@ -24,7 +24,6 @@
 ENTRY(csum_partial_copy_nocheck)
 	MVC	.S2	ILC,B30
 
-	MV	.D1X	B6,A31		; given csum
 	ZERO	.D1	A9		; csum (a side)
 ||	ZERO	.D2	B9		; csum (b side)
 ||	SHRU	.S2X	A6,2,B5		; len / 4
@@ -144,8 +143,7 @@ L91:	SHRU	.S2X	A9,16,B4
 	SHRU	.S1	A9,16,A0
    [A0]	BNOP	.S1	L91,5
 
-L10:	ADD	.D1	A31,A9,A9
-	MV	.D1	A9,A4
+L10:	MV	.D1	A9,A4
 
 	BNOP	.S2	B3,4
 	MVC	.S2	B30,ILC
diff --git a/arch/m68k/include/asm/checksum.h b/arch/m68k/include/asm/checksum.h
index ab16881d84cb..d5e74c64b6cd 100644
--- a/arch/m68k/include/asm/checksum.h
+++ b/arch/m68k/include/asm/checksum.h
@@ -38,8 +38,7 @@ extern __wsum csum_and_copy_from_user(const void __user *src,
 						int *csum_err);
 
 extern __wsum csum_partial_copy_nocheck(const void *src,
-					      void *dst, int len,
-					      __wsum sum);
+					      void *dst, int len);
 
 /*
  *	This is a version of ip_fast_csum() optimized for IP headers,
diff --git a/arch/m68k/lib/checksum.c b/arch/m68k/lib/checksum.c
index 31797be9a3dc..86ddd2ee187d 100644
--- a/arch/m68k/lib/checksum.c
+++ b/arch/m68k/lib/checksum.c
@@ -324,9 +324,10 @@ EXPORT_SYMBOL(csum_and_copy_from_user);
  */
 
 __wsum
-csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
+csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
 	unsigned long tmp1, tmp2;
+	__wsum sum = 0;
 	__asm__("movel %2,%4\n\t"
 		"btst #1,%4\n\t"	/* Check alignment */
 		"jeq 2f\n\t"
diff --git a/arch/mips/include/asm/checksum.h b/arch/mips/include/asm/checksum.h
index abdf1086873d..ec3159dbc1b3 100644
--- a/arch/mips/include/asm/checksum.h
+++ b/arch/mips/include/asm/checksum.h
@@ -102,8 +102,11 @@ __wsum csum_and_copy_to_user(const void *src, void __user *dst, int len,
  * we have just one address space, so this is identical to the above)
  */
 #define _HAVE_ARCH_CSUM_AND_COPY
-__wsum csum_partial_copy_nocheck(const void *src, void *dst,
-				       int len, __wsum sum);
+__wsum __csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
+static inline __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
+{
+	return __csum_partial_copy_nocheck(src, dst, len, 0);
+}
 
 /*
  *	Fold a partial checksum without adding pseudo headers
diff --git a/arch/mips/lib/csum_partial.S b/arch/mips/lib/csum_partial.S
index 87fda0713b84..8d70855b0914 100644
--- a/arch/mips/lib/csum_partial.S
+++ b/arch/mips/lib/csum_partial.S
@@ -462,8 +462,8 @@ EXPORT_SYMBOL(csum_partial)
 	lw	errptr, 16(sp)
 #endif
 	.if \__nocheck == 1
-	FEXPORT(csum_partial_copy_nocheck)
-	EXPORT_SYMBOL(csum_partial_copy_nocheck)
+	FEXPORT(__csum_partial_copy_nocheck)
+	EXPORT_SYMBOL(__csum_partial_copy_nocheck)
 	.endif
 	move	sum, zero
 	move	odd, zero
diff --git a/arch/powerpc/include/asm/checksum.h b/arch/powerpc/include/asm/checksum.h
index d75fc5bf8f37..64299785f639 100644
--- a/arch/powerpc/include/asm/checksum.h
+++ b/arch/powerpc/include/asm/checksum.h
@@ -30,8 +30,8 @@ extern __wsum csum_and_copy_to_user(const void *src, void __user *dst,
 				    int len, __wsum sum, int *err_ptr);
 
 #define _HAVE_ARCH_CSUM_AND_COPY
-#define csum_partial_copy_nocheck(src, dst, len, sum)   \
-        csum_partial_copy_generic((src), (dst), (len), (sum), NULL, NULL)
+#define csum_partial_copy_nocheck(src, dst, len)   \
+        csum_partial_copy_generic((src), (dst), (len), 0, NULL, NULL)
 
 
 /*
diff --git a/arch/sh/include/asm/checksum_32.h b/arch/sh/include/asm/checksum_32.h
index 87269642d78d..e8bf84d3b843 100644
--- a/arch/sh/include/asm/checksum_32.h
+++ b/arch/sh/include/asm/checksum_32.h
@@ -43,10 +43,9 @@ asmlinkage __wsum csum_partial_copy_generic(const void *src, void *dst,
  *	access_ok().
  */
 static inline
-__wsum csum_partial_copy_nocheck(const void *src, void *dst,
-				 int len, __wsum sum)
+__wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
-	return csum_partial_copy_generic(src, dst, len, sum, NULL, NULL);
+	return csum_partial_copy_generic(src, dst, len, 0, NULL, NULL);
 }
 
 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
diff --git a/arch/sparc/include/asm/checksum_32.h b/arch/sparc/include/asm/checksum_32.h
index 479a0b812af5..d21d114436ba 100644
--- a/arch/sparc/include/asm/checksum_32.h
+++ b/arch/sparc/include/asm/checksum_32.h
@@ -42,7 +42,7 @@ __wsum csum_partial(const void *buff, int len, __wsum sum);
 unsigned int __csum_partial_copy_sparc_generic (const unsigned char *, unsigned char *);
 
 static inline __wsum
-csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
+csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
 	register unsigned int ret asm("o0") = (unsigned int)src;
 	register char *d asm("o1") = dst;
@@ -52,7 +52,7 @@ csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
 		"call __csum_partial_copy_sparc_generic\n\t"
 		" mov %6, %%g7\n"
 	: "=&r" (ret), "=&r" (d), "=&r" (l)
-	: "0" (ret), "1" (d), "2" (l), "r" (sum)
+	: "0" (ret), "1" (d), "2" (l), "r" (0)
 	: "o2", "o3", "o4", "o5", "o7",
 	  "g2", "g3", "g4", "g5", "g7",
 	  "memory", "cc");
diff --git a/arch/sparc/include/asm/checksum_64.h b/arch/sparc/include/asm/checksum_64.h
index 0fa4433f5662..7aebdbe3ac96 100644
--- a/arch/sparc/include/asm/checksum_64.h
+++ b/arch/sparc/include/asm/checksum_64.h
@@ -38,8 +38,12 @@ __wsum csum_partial(const void * buff, int len, __wsum sum);
  * here even more important to align src and dst on a 32-bit (or even
  * better 64-bit) boundary
  */
-__wsum csum_partial_copy_nocheck(const void *src, void *dst,
-				 int len, __wsum sum);
+__wsum __csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
+
+static inline __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
+{
+	return __csum_partial_copy_nocheck(src, dst, len, 0);
+}
 
 long __csum_partial_copy_from_user(const void __user *src,
 				   void *dst, int len,
diff --git a/arch/sparc/lib/csum_copy.S b/arch/sparc/lib/csum_copy.S
index 26c644ba3ecb..72c900d21b12 100644
--- a/arch/sparc/lib/csum_copy.S
+++ b/arch/sparc/lib/csum_copy.S
@@ -33,7 +33,7 @@
 #endif
 
 #ifndef FUNC_NAME
-#define FUNC_NAME	csum_partial_copy_nocheck
+#define FUNC_NAME	__csum_partial_copy_nocheck
 #endif
 
 	.register	%g2, #scratch
diff --git a/arch/x86/include/asm/checksum_32.h b/arch/x86/include/asm/checksum_32.h
index 11624c8a9d8d..137a3033edcc 100644
--- a/arch/x86/include/asm/checksum_32.h
+++ b/arch/x86/include/asm/checksum_32.h
@@ -38,10 +38,9 @@ asmlinkage __wsum csum_partial_copy_generic(const void *src, void *dst,
  *	If you use these functions directly please don't forget the
  *	access_ok().
  */
-static inline __wsum csum_partial_copy_nocheck(const void *src, void *dst,
-					       int len, __wsum sum)
+static inline __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
-	return csum_partial_copy_generic(src, dst, len, sum, NULL, NULL);
+	return csum_partial_copy_generic(src, dst, len, 0, NULL, NULL);
 }
 
 static inline __wsum csum_and_copy_from_user(const void __user *src,
diff --git a/arch/x86/include/asm/checksum_64.h b/arch/x86/include/asm/checksum_64.h
index 0a289b87e872..5339f5dfc776 100644
--- a/arch/x86/include/asm/checksum_64.h
+++ b/arch/x86/include/asm/checksum_64.h
@@ -139,8 +139,7 @@ extern __wsum csum_and_copy_from_user(const void __user *src, void *dst,
 					  int len, __wsum isum, int *errp);
 extern __wsum csum_and_copy_to_user(const void *src, void __user *dst,
 					int len, __wsum isum, int *errp);
-extern __wsum csum_partial_copy_nocheck(const void *src, void *dst,
-					int len, __wsum sum);
+extern __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len);
 
 /**
  * ip_compute_csum - Compute an 16bit IP checksum.
diff --git a/arch/x86/lib/csum-wrappers_64.c b/arch/x86/lib/csum-wrappers_64.c
index ee63d7576fd2..245f929a1c2c 100644
--- a/arch/x86/lib/csum-wrappers_64.c
+++ b/arch/x86/lib/csum-wrappers_64.c
@@ -129,9 +129,9 @@ EXPORT_SYMBOL(csum_and_copy_to_user);
  * Returns an 32bit unfolded checksum of the buffer.
  */
 __wsum
-csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
+csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
-	return csum_partial_copy_generic(src, dst, len, sum, NULL, NULL);
+	return csum_partial_copy_generic(src, dst, len, 0, NULL, NULL);
 }
 EXPORT_SYMBOL(csum_partial_copy_nocheck);
 
diff --git a/arch/xtensa/include/asm/checksum.h b/arch/xtensa/include/asm/checksum.h
index 0c879099977f..dc09448935bf 100644
--- a/arch/xtensa/include/asm/checksum.h
+++ b/arch/xtensa/include/asm/checksum.h
@@ -47,10 +47,9 @@ asmlinkage __wsum csum_partial_copy_generic(const void *src, void *dst,
  *	passed in an incorrect kernel address to one of these functions.
  */
 static inline
-__wsum csum_partial_copy_nocheck(const void *src, void *dst,
-					int len, __wsum sum)
+__wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
-	return csum_partial_copy_generic(src, dst, len, sum, NULL, NULL);
+	return csum_partial_copy_generic(src, dst, len, 0, NULL, NULL);
 }
 
 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
diff --git a/drivers/net/ethernet/3com/typhoon.c b/drivers/net/ethernet/3com/typhoon.c
index d3b30bacc94e..049cc0158a64 100644
--- a/drivers/net/ethernet/3com/typhoon.c
+++ b/drivers/net/ethernet/3com/typhoon.c
@@ -1419,8 +1419,7 @@ typhoon_download_firmware(struct typhoon *tp)
 			 * the checksum, we can do this once, at the end.
 			 */
 			csum = csum_fold(csum_partial_copy_nocheck(image_data,
-								   dpage, len,
-								   0));
+								   dpage, len));
 
 			iowrite32(len, ioaddr + TYPHOON_REG_BOOT_LENGTH);
 			iowrite32(le16_to_cpu((__force __le16)csum),
diff --git a/include/net/checksum.h b/include/net/checksum.h
index db9d02b5f88a..1029191986e3 100644
--- a/include/net/checksum.h
+++ b/include/net/checksum.h
@@ -49,10 +49,10 @@ static __inline__ __wsum csum_and_copy_to_user
 
 #ifndef _HAVE_ARCH_CSUM_AND_COPY
 static inline __wsum
-csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
+csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
 	memcpy(dst, src, len);
-	return csum_partial(dst, len, sum);
+	return csum_partial(dst, len, 0);
 }
 #endif
 
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 5e40786c8f12..84f3a9156684 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -581,7 +581,7 @@ static size_t copy_pipe_to_iter(const void *addr, size_t bytes,
 static __wsum csum_and_memcpy(void *to, const void *from, size_t len,
 			      __wsum sum, size_t off)
 {
-	__wsum next = csum_partial_copy_nocheck(from, to, len, 0);
+	__wsum next = csum_partial_copy_nocheck(from, to, len);
 	return csum_block_add(sum, next, off);
 }
 
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 6e806da2913e..48dd4757b898 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -2736,7 +2736,7 @@ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset,
 		if (copy > len)
 			copy = len;
 		csum = csum_partial_copy_nocheck(skb->data + offset, to,
-						 copy, 0);
+						 copy);
 		if ((len -= copy) == 0)
 			return csum;
 		offset += copy;
@@ -2766,7 +2766,7 @@ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset,
 				vaddr = kmap_atomic(p);
 				csum2 = csum_partial_copy_nocheck(vaddr + p_off,
 								  to + copied,
-								  p_len, 0);
+								  p_len);
 				kunmap_atomic(vaddr);
 				csum = csum_block_add(csum, csum2, pos);
 				pos += p_len;
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index e23dd5fc2e73..bdaaee52c41b 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -381,7 +381,7 @@ static void icmp_push_reply(struct icmp_bxm *icmp_param,
 
 		csum = csum_partial_copy_nocheck((void *)&icmp_param->data,
 						 (char *)icmph,
-						 icmp_param->head_len, 0);
+						 icmp_param->head_len);
 		skb_queue_walk(&sk->sk_write_queue, skb1) {
 			csum = csum_add(csum, skb1->csum);
 		}
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 5bd059853376..bd79ea3e8c44 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -1648,7 +1648,7 @@ static int ip_reply_glue_bits(void *dptr, char *to, int offset,
 {
 	__wsum csum;
 
-	csum = csum_partial_copy_nocheck(dptr+offset, to, len, 0);
+	csum = csum_partial_copy_nocheck(dptr+offset, to, len);
 	skb->csum = csum_block_add(skb->csum, csum, odd);
 	return 0;
 }
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 6fd4330287c2..79392154c30a 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -478,7 +478,7 @@ static int raw_getfrag(void *from, char *to, int offset, int len, int odd,
 			skb->csum = csum_block_add(
 				skb->csum,
 				csum_partial_copy_nocheck(rfv->hdr.c + offset,
-							  to, copy, 0),
+							  to, copy),
 				odd);
 
 		odd = 0;
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 874f01cd7aec..6e4ab80a3b94 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -746,7 +746,7 @@ static int raw6_getfrag(void *from, char *to, int offset, int len, int odd,
 			skb->csum = csum_block_add(
 				skb->csum,
 				csum_partial_copy_nocheck(rfv->c + offset,
-							  to, copy, 0),
+							  to, copy),
 				odd);
 
 		odd = 0;
-- 
cgit v1.2.3-59-g8ed1b


From c693cc4676a055c4126e487b30b0a96ea7ec9936 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Sat, 11 Jul 2020 00:27:49 -0400
Subject: saner calling conventions for csum_and_copy_..._user()

All callers of these primitives will
	* discard anything we might've copied in case of error
	* ignore the csum value in case of error
	* always pass 0xffffffff as the initial sum, so the
resulting csum value (in case of success, that is) will never be 0.

That suggest the following calling conventions:
	* don't pass err_ptr - just return 0 on error.
	* don't bother with zeroing destination, etc. in case of error
	* don't pass the initial sum - just use 0xffffffff.

This commit does the minimal conversion in the instances of csum_and_copy_...();
the changes of actual asm code behind them are done later in the series.
Note that this asm code is often shared with csum_partial_copy_nocheck();
the difference is that csum_partial_copy_nocheck() passes 0 for initial
sum while csum_and_copy_..._user() pass 0xffffffff.  Fortunately, we are
free to pass 0xffffffff in all cases and subsequent patches will use that
freedom without any special comments.

A part that could be split off: parisc and uml/i386 claimed to have
csum_and_copy_to_user() instances of their own, but those were identical
to the generic one, so we simply drop them.  Not sure if it's worth
a separate commit...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 arch/alpha/include/asm/checksum.h    |  2 +-
 arch/alpha/lib/csum_partial_copy.c   | 25 ++++++-------
 arch/arm/include/asm/checksum.h      | 13 ++++---
 arch/m68k/include/asm/checksum.h     |  3 +-
 arch/m68k/lib/checksum.c             |  8 ++---
 arch/mips/include/asm/checksum.h     | 46 ++++++++++++------------
 arch/parisc/include/asm/checksum.h   | 20 -----------
 arch/powerpc/include/asm/checksum.h  |  4 +--
 arch/powerpc/lib/checksum_wrappers.c | 68 +++++++++++-------------------------
 arch/sh/include/asm/checksum_32.h    | 36 +++++++++----------
 arch/sparc/include/asm/checksum_32.h | 65 ++++++++++++++++------------------
 arch/sparc/include/asm/checksum_64.h | 14 ++++----
 arch/x86/include/asm/checksum_32.h   | 35 ++++++++-----------
 arch/x86/include/asm/checksum_64.h   |  6 ++--
 arch/x86/lib/csum-wrappers_64.c      | 38 +++++++++-----------
 arch/x86/um/asm/checksum_32.h        | 23 ------------
 arch/xtensa/include/asm/checksum.h   | 30 ++++++++--------
 include/net/checksum.h               | 15 ++++----
 lib/iov_iter.c                       | 19 +++++-----
 19 files changed, 183 insertions(+), 287 deletions(-)

(limited to 'arch/alpha')

diff --git a/arch/alpha/include/asm/checksum.h b/arch/alpha/include/asm/checksum.h
index 84f9faea864a..99d631e146b2 100644
--- a/arch/alpha/include/asm/checksum.h
+++ b/arch/alpha/include/asm/checksum.h
@@ -43,7 +43,7 @@ extern __wsum csum_partial(const void *buff, int len, __wsum sum);
  */
 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
 #define _HAVE_ARCH_CSUM_AND_COPY
-__wsum csum_and_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *errp);
+__wsum csum_and_copy_from_user(const void __user *src, void *dst, int len);
 
 __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len);
 
diff --git a/arch/alpha/lib/csum_partial_copy.c b/arch/alpha/lib/csum_partial_copy.c
index f363dc89fcbe..3c0e89c39ddb 100644
--- a/arch/alpha/lib/csum_partial_copy.c
+++ b/arch/alpha/lib/csum_partial_copy.c
@@ -325,30 +325,27 @@ csum_partial_cfu_unaligned(const unsigned long __user * src,
 }
 
 __wsum
-csum_and_copy_from_user(const void __user *src, void *dst, int len,
-			       __wsum sum, int *errp)
+csum_and_copy_from_user(const void __user *src, void *dst, int len)
 {
-	unsigned long checksum = (__force u32) sum;
+	unsigned long checksum = ~0U;
 	unsigned long soff = 7 & (unsigned long) src;
 	unsigned long doff = 7 & (unsigned long) dst;
+	int err = 0;
 
 	if (len) {
-		if (!access_ok(src, len)) {
-			if (errp) *errp = -EFAULT;
-			memset(dst, 0, len);
-			return sum;
-		}
+		if (!access_ok(src, len))
+			return 0;
 		if (!doff) {
 			if (!soff)
 				checksum = csum_partial_cfu_aligned(
 					(const unsigned long __user *) src,
 					(unsigned long *) dst,
-					len-8, checksum, errp);
+					len-8, checksum, &err);
 			else
 				checksum = csum_partial_cfu_dest_aligned(
 					(const unsigned long __user *) src,
 					(unsigned long *) dst,
-					soff, len-8, checksum, errp);
+					soff, len-8, checksum, &err);
 		} else {
 			unsigned long partial_dest;
 			ldq_u(partial_dest, dst);
@@ -357,15 +354,15 @@ csum_and_copy_from_user(const void __user *src, void *dst, int len,
 					(const unsigned long __user *) src,
 					(unsigned long *) dst,
 					doff, len-8, checksum,
-					partial_dest, errp);
+					partial_dest, &err);
 			else
 				checksum = csum_partial_cfu_unaligned(
 					(const unsigned long __user *) src,
 					(unsigned long *) dst,
 					soff, doff, len-8, checksum,
-					partial_dest, errp);
+					partial_dest, &err);
 		}
-		checksum = from64to16 (checksum);
+		checksum = err ? 0 : from64to16 (checksum);
 	}
 	return (__force __wsum)checksum;
 }
@@ -378,7 +375,7 @@ csum_partial_copy_nocheck(const void *src, void *dst, int len)
 	mm_segment_t oldfs = get_fs();
 	set_fs(KERNEL_DS);
 	checksum = csum_and_copy_from_user((__force const void __user *)src,
-						dst, len, 0, NULL);
+						dst, len);
 	set_fs(oldfs);
 	return checksum;
 }
diff --git a/arch/arm/include/asm/checksum.h b/arch/arm/include/asm/checksum.h
index 7612b2bd4e9b..1601c132b064 100644
--- a/arch/arm/include/asm/checksum.h
+++ b/arch/arm/include/asm/checksum.h
@@ -43,16 +43,15 @@ csum_partial_copy_from_user(const void __user *src, void *dst, int len, __wsum s
 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
 #define _HAVE_ARCH_CSUM_AND_COPY
 static inline
-__wsum csum_and_copy_from_user (const void __user *src, void *dst,
-				      int len, __wsum sum, int *err_ptr)
+__wsum csum_and_copy_from_user(const void __user *src, void *dst, int len)
 {
-	if (access_ok(src, len))
-		return csum_partial_copy_from_user(src, dst, len, sum, err_ptr);
+	int err = 0;
 
-	if (len)
-		*err_ptr = -EFAULT;
+	if (!access_ok(src, len))
+		return 0;
 
-	return sum;
+	sum = csum_partial_copy_from_user(src, dst, len, ~0U, &err);
+	return err ? 0 : sum;
 }
 
 /*
diff --git a/arch/m68k/include/asm/checksum.h b/arch/m68k/include/asm/checksum.h
index d5e74c64b6cd..692e7b6cc042 100644
--- a/arch/m68k/include/asm/checksum.h
+++ b/arch/m68k/include/asm/checksum.h
@@ -34,8 +34,7 @@ __wsum csum_partial(const void *buff, int len, __wsum sum);
 #define _HAVE_ARCH_CSUM_AND_COPY
 extern __wsum csum_and_copy_from_user(const void __user *src,
 						void *dst,
-						int len, __wsum sum,
-						int *csum_err);
+						int len);
 
 extern __wsum csum_partial_copy_nocheck(const void *src,
 					      void *dst, int len);
diff --git a/arch/m68k/lib/checksum.c b/arch/m68k/lib/checksum.c
index 86ddd2ee187d..3aeca261f622 100644
--- a/arch/m68k/lib/checksum.c
+++ b/arch/m68k/lib/checksum.c
@@ -129,8 +129,7 @@ EXPORT_SYMBOL(csum_partial);
  */
 
 __wsum
-csum_and_copy_from_user(const void __user *src, void *dst,
-			    int len, __wsum sum, int *csum_err)
+csum_and_copy_from_user(const void __user *src, void *dst, int len)
 {
 	/*
 	 * GCC doesn't like more than 10 operands for the asm
@@ -138,6 +137,7 @@ csum_and_copy_from_user(const void __user *src, void *dst,
 	 * code.
 	 */
 	unsigned long tmp1, tmp2;
+	__wsum sum = ~0U;
 
 	__asm__("movel %2,%4\n\t"
 		"btst #1,%4\n\t"	/* Check alignment */
@@ -311,9 +311,7 @@ csum_and_copy_from_user(const void __user *src, void *dst,
 		: "0" (sum), "1" (len), "2" (src), "3" (dst)
 	    );
 
-	*csum_err = tmp2;
-
-	return(sum);
+	return tmp2 ? 0 : sum;
 }
 
 EXPORT_SYMBOL(csum_and_copy_from_user);
diff --git a/arch/mips/include/asm/checksum.h b/arch/mips/include/asm/checksum.h
index ec3159dbc1b3..9dfce3522760 100644
--- a/arch/mips/include/asm/checksum.h
+++ b/arch/mips/include/asm/checksum.h
@@ -60,16 +60,15 @@ __wsum csum_partial_copy_from_user(const void __user *src, void *dst, int len,
 
 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
 static inline
-__wsum csum_and_copy_from_user(const void __user *src, void *dst,
-			       int len, __wsum sum, int *err_ptr)
+__wsum csum_and_copy_from_user(const void __user *src, void *dst, int len)
 {
-	if (access_ok(src, len))
-		return csum_partial_copy_from_user(src, dst, len, sum,
-						   err_ptr);
-	if (len)
-		*err_ptr = -EFAULT;
+	__wsum sum = ~0U;
+	int err = 0;
 
-	return sum;
+	if (!access_ok(src, len))
+		return 0;
+	sum = csum_partial_copy_from_user(src, dst, len, sum, &err);
+	return err ? 0 : sum;
 }
 
 /*
@@ -77,24 +76,23 @@ __wsum csum_and_copy_from_user(const void __user *src, void *dst,
  */
 #define HAVE_CSUM_COPY_USER
 static inline
-__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len,
-			     __wsum sum, int *err_ptr)
+__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len)
 {
+	int err = 0;
+	__wsum sum = ~0U;
+
 	might_fault();
-	if (access_ok(dst, len)) {
-		if (uaccess_kernel())
-			return __csum_partial_copy_kernel(src,
-							  (__force void *)dst,
-							  len, sum, err_ptr);
-		else
-			return __csum_partial_copy_to_user(src,
-							   (__force void *)dst,
-							   len, sum, err_ptr);
-	}
-	if (len)
-		*err_ptr = -EFAULT;
-
-	return (__force __wsum)-1; /* invalid checksum */
+	if (!access_ok(dst, len))
+		return 0;
+	if (uaccess_kernel())
+		sum = __csum_partial_copy_kernel(src,
+						  (__force void *)dst,
+						  len, sum, &err);
+	else
+		sum = __csum_partial_copy_to_user(src,
+						   (__force void *)dst,
+						   len, sum, &err);
+	return err ? 0 : sum;
 }
 
 /*
diff --git a/arch/parisc/include/asm/checksum.h b/arch/parisc/include/asm/checksum.h
index 522cd574c068..3c43baca7b39 100644
--- a/arch/parisc/include/asm/checksum.h
+++ b/arch/parisc/include/asm/checksum.h
@@ -173,25 +173,5 @@ static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
 	return csum_fold(sum);
 }
 
-/* 
- *	Copy and checksum to user
- */
-#define HAVE_CSUM_COPY_USER
-static __inline__ __wsum csum_and_copy_to_user(const void *src,
-						      void __user *dst,
-						      int len, __wsum sum,
-						      int *err_ptr)
-{
-	/* code stolen from include/asm-mips64 */
-	sum = csum_partial(src, len, sum);
-	 
-	if (copy_to_user(dst, src, len)) {
-		*err_ptr = -EFAULT;
-		return (__force __wsum)-1;
-	}
-
-	return sum;
-}
-
 #endif
 
diff --git a/arch/powerpc/include/asm/checksum.h b/arch/powerpc/include/asm/checksum.h
index 64299785f639..dba685d984c0 100644
--- a/arch/powerpc/include/asm/checksum.h
+++ b/arch/powerpc/include/asm/checksum.h
@@ -24,10 +24,10 @@ extern __wsum csum_partial_copy_generic(const void *src, void *dst,
 
 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
 extern __wsum csum_and_copy_from_user(const void __user *src, void *dst,
-				      int len, __wsum sum, int *err_ptr);
+				      int len);
 #define HAVE_CSUM_COPY_USER
 extern __wsum csum_and_copy_to_user(const void *src, void __user *dst,
-				    int len, __wsum sum, int *err_ptr);
+				    int len);
 
 #define _HAVE_ARCH_CSUM_AND_COPY
 #define csum_partial_copy_nocheck(src, dst, len)   \
diff --git a/arch/powerpc/lib/checksum_wrappers.c b/arch/powerpc/lib/checksum_wrappers.c
index fabe4db28726..b1faa82dd8af 100644
--- a/arch/powerpc/lib/checksum_wrappers.c
+++ b/arch/powerpc/lib/checksum_wrappers.c
@@ -12,82 +12,56 @@
 #include <linux/uaccess.h>
 
 __wsum csum_and_copy_from_user(const void __user *src, void *dst,
-			       int len, __wsum sum, int *err_ptr)
+			       int len)
 {
 	unsigned int csum;
+	int err = 0;
 
 	might_sleep();
-	allow_read_from_user(src, len);
-
-	*err_ptr = 0;
 
-	if (!len) {
-		csum = 0;
-		goto out;
-	}
+	if (unlikely(!access_ok(src, len)))
+		return 0;
 
-	if (unlikely((len < 0) || !access_ok(src, len))) {
-		*err_ptr = -EFAULT;
-		csum = (__force unsigned int)sum;
-		goto out;
-	}
+	allow_read_from_user(src, len);
 
 	csum = csum_partial_copy_generic((void __force *)src, dst,
-					 len, sum, err_ptr, NULL);
+					 len, ~0U, &err, NULL);
 
-	if (unlikely(*err_ptr)) {
+	if (unlikely(err)) {
 		int missing = __copy_from_user(dst, src, len);
 
-		if (missing) {
-			memset(dst + len - missing, 0, missing);
-			*err_ptr = -EFAULT;
-		} else {
-			*err_ptr = 0;
-		}
-
-		csum = csum_partial(dst, len, sum);
+		if (missing)
+			csum = 0;
+		else
+			csum = csum_partial(dst, len, ~0U);
 	}
 
-out:
 	prevent_read_from_user(src, len);
 	return (__force __wsum)csum;
 }
 EXPORT_SYMBOL(csum_and_copy_from_user);
 
-__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len,
-			     __wsum sum, int *err_ptr)
+__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len)
 {
 	unsigned int csum;
+	int err = 0;
 
 	might_sleep();
-	allow_write_to_user(dst, len);
-
-	*err_ptr = 0;
-
-	if (!len) {
-		csum = 0;
-		goto out;
-	}
+	if (unlikely(!access_ok(dst, len)))
+		return 0;
 
-	if (unlikely((len < 0) || !access_ok(dst, len))) {
-		*err_ptr = -EFAULT;
-		csum = -1; /* invalid checksum */
-		goto out;
-	}
+	allow_write_to_user(dst, len);
 
 	csum = csum_partial_copy_generic(src, (void __force *)dst,
-					 len, sum, NULL, err_ptr);
+					 len, ~0U, NULL, &err);
 
-	if (unlikely(*err_ptr)) {
-		csum = csum_partial(src, len, sum);
+	if (unlikely(err)) {
+		csum = csum_partial(src, len, ~0U);
 
-		if (copy_to_user(dst, src, len)) {
-			*err_ptr = -EFAULT;
-			csum = -1; /* invalid checksum */
-		}
+		if (copy_to_user(dst, src, len))
+			csum = 0;
 	}
 
-out:
 	prevent_write_to_user(dst, len);
 	return (__force __wsum)csum;
 }
diff --git a/arch/sh/include/asm/checksum_32.h b/arch/sh/include/asm/checksum_32.h
index e8bf84d3b843..a08e8eb924ed 100644
--- a/arch/sh/include/asm/checksum_32.h
+++ b/arch/sh/include/asm/checksum_32.h
@@ -50,15 +50,16 @@ __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
 
 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
 static inline
-__wsum csum_and_copy_from_user(const void __user *src, void *dst,
-				   int len, __wsum sum, int *err_ptr)
+__wsum csum_and_copy_from_user(const void __user *src, void *dst, int len)
 {
-	if (access_ok(src, len))
-		return csum_partial_copy_generic((__force const void *)src, dst,
-					len, sum, err_ptr, NULL);
-	if (len)
-		*err_ptr = -EFAULT;
-	return sum;
+	int err = 0;
+	__wsum sum = ~0U;
+
+	if (!access_ok(src, len))
+		return 0;
+	sum = csum_partial_copy_generic((__force const void *)src, dst,
+					len, sum, &err, NULL);
+	return err ? 0 : sum;
 }
 
 /*
@@ -199,16 +200,15 @@ static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
 #define HAVE_CSUM_COPY_USER
 static inline __wsum csum_and_copy_to_user(const void *src,
 					   void __user *dst,
-					   int len, __wsum sum,
-					   int *err_ptr)
+					   int len)
 {
-	if (access_ok(dst, len))
-		return csum_partial_copy_generic((__force const void *)src,
-						dst, len, sum, NULL, err_ptr);
-
-	if (len)
-		*err_ptr = -EFAULT;
-
-	return (__force __wsum)-1; /* invalid checksum */
+	int err = 0;
+	__wsum sum = ~0U;
+
+	if (!access_ok(dst, len))
+		return 0;
+	sum = csum_partial_copy_generic((__force const void *)src,
+						dst, len, sum, NULL, &err);
+	return err ? 0 : sum;
 }
 #endif /* __ASM_SH_CHECKSUM_H */
diff --git a/arch/sparc/include/asm/checksum_32.h b/arch/sparc/include/asm/checksum_32.h
index d21d114436ba..b5873b7b7bf0 100644
--- a/arch/sparc/include/asm/checksum_32.h
+++ b/arch/sparc/include/asm/checksum_32.h
@@ -60,19 +60,16 @@ csum_partial_copy_nocheck(const void *src, void *dst, int len)
 }
 
 static inline __wsum
-csum_and_copy_from_user(const void __user *src, void *dst, int len,
-			    __wsum sum, int *err)
+csum_and_copy_from_user(const void __user *src, void *dst, int len)
   {
 	register unsigned long ret asm("o0") = (unsigned long)src;
 	register char *d asm("o1") = dst;
 	register int l asm("g1") = len;
-	register __wsum s asm("g7") = sum;
+	register __wsum s asm("g7") = ~0U;
+	int err = 0;
 
-	if (unlikely(!access_ok(src, len))) {
-		if (len)
-			*err = -EFAULT;
-		return sum;
-	}
+	if (unlikely(!access_ok(src, len)))
+		return 0;
 
 	__asm__ __volatile__ (
 	".section __ex_table,#alloc\n\t"
@@ -83,42 +80,40 @@ csum_and_copy_from_user(const void __user *src, void *dst, int len,
 	"call __csum_partial_copy_sparc_generic\n\t"
 	" st %8, [%%sp + 64]\n"
 	: "=&r" (ret), "=&r" (d), "=&r" (l), "=&r" (s)
-	: "0" (ret), "1" (d), "2" (l), "3" (s), "r" (err)
+	: "0" (ret), "1" (d), "2" (l), "3" (s), "r" (&err)
 	: "o2", "o3", "o4", "o5", "o7", "g2", "g3", "g4", "g5",
 	  "cc", "memory");
-	return (__force __wsum)ret;
+	return err ? 0 : (__force __wsum)ret;
 }
 
 #define HAVE_CSUM_COPY_USER
 
 static inline __wsum
-csum_and_copy_to_user(const void *src, void __user *dst, int len,
-			  __wsum sum, int *err)
+csum_and_copy_to_user(const void *src, void __user *dst, int len)
 {
-	if (!access_ok(dst, len)) {
-		*err = -EFAULT;
-		return sum;
-	} else {
-		register unsigned long ret asm("o0") = (unsigned long)src;
-		register char __user *d asm("o1") = dst;
-		register int l asm("g1") = len;
-		register __wsum s asm("g7") = sum;
+	register unsigned long ret asm("o0") = (unsigned long)src;
+	register char __user *d asm("o1") = dst;
+	register int l asm("g1") = len;
+	register __wsum s asm("g7") = ~0U;
+	int err = 0;
 
-		__asm__ __volatile__ (
-		".section __ex_table,#alloc\n\t"
-		".align 4\n\t"
-		".word 1f,1\n\t"
-		".previous\n"
-		"1:\n\t"
-		"call __csum_partial_copy_sparc_generic\n\t"
-		" st %8, [%%sp + 64]\n"
-		: "=&r" (ret), "=&r" (d), "=&r" (l), "=&r" (s)
-		: "0" (ret), "1" (d), "2" (l), "3" (s), "r" (err)
-		: "o2", "o3", "o4", "o5", "o7",
-		  "g2", "g3", "g4", "g5",
-		  "cc", "memory");
-		return (__force __wsum)ret;
-	}
+	if (!access_ok(dst, len))
+		return 0;
+
+	__asm__ __volatile__ (
+	".section __ex_table,#alloc\n\t"
+	".align 4\n\t"
+	".word 1f,1\n\t"
+	".previous\n"
+	"1:\n\t"
+	"call __csum_partial_copy_sparc_generic\n\t"
+	" st %8, [%%sp + 64]\n"
+	: "=&r" (ret), "=&r" (d), "=&r" (l), "=&r" (s)
+	: "0" (ret), "1" (d), "2" (l), "3" (s), "r" (&err)
+	: "o2", "o3", "o4", "o5", "o7",
+	  "g2", "g3", "g4", "g5",
+	  "cc", "memory");
+	return err ? 0 : (__force __wsum)ret;
 }
 
 /* ihl is always 5 or greater, almost always is 5, and iph is word aligned
diff --git a/arch/sparc/include/asm/checksum_64.h b/arch/sparc/include/asm/checksum_64.h
index 7aebdbe3ac96..4d0bbff43e62 100644
--- a/arch/sparc/include/asm/checksum_64.h
+++ b/arch/sparc/include/asm/checksum_64.h
@@ -51,12 +51,11 @@ long __csum_partial_copy_from_user(const void __user *src,
 
 static inline __wsum
 csum_and_copy_from_user(const void __user *src,
-			    void *dst, int len,
-			    __wsum sum, int *err)
+			    void *dst, int len)
 {
-	long ret = __csum_partial_copy_from_user(src, dst, len, sum);
+	long ret = __csum_partial_copy_from_user(src, dst, len, ~0U);
 	if (ret < 0)
-		*err = -EFAULT;
+		return 0;
 	return (__force __wsum) ret;
 }
 
@@ -70,12 +69,11 @@ long __csum_partial_copy_to_user(const void *src,
 
 static inline __wsum
 csum_and_copy_to_user(const void *src,
-		      void __user *dst, int len,
-		      __wsum sum, int *err)
+		      void __user *dst, int len)
 {
-	long ret = __csum_partial_copy_to_user(src, dst, len, sum);
+	long ret = __csum_partial_copy_to_user(src, dst, len, ~0U);
 	if (ret < 0)
-		*err = -EFAULT;
+		return 0;
 	return (__force __wsum) ret;
 }
 
diff --git a/arch/x86/include/asm/checksum_32.h b/arch/x86/include/asm/checksum_32.h
index 137a3033edcc..5948cde9e4ad 100644
--- a/arch/x86/include/asm/checksum_32.h
+++ b/arch/x86/include/asm/checksum_32.h
@@ -44,22 +44,19 @@ static inline __wsum csum_partial_copy_nocheck(const void *src, void *dst, int l
 }
 
 static inline __wsum csum_and_copy_from_user(const void __user *src,
-					     void *dst, int len,
-					     __wsum sum, int *err_ptr)
+					     void *dst, int len)
 {
 	__wsum ret;
+	int err = 0;
 
 	might_sleep();
-	if (!user_access_begin(src, len)) {
-		if (len)
-			*err_ptr = -EFAULT;
-		return sum;
-	}
+	if (!user_access_begin(src, len))
+		return 0;
 	ret = csum_partial_copy_generic((__force void *)src, dst,
-					len, sum, err_ptr, NULL);
+					len, ~0U, &err, NULL);
 	user_access_end();
 
-	return ret;
+	return err ? 0 : ret;
 }
 
 /*
@@ -177,23 +174,19 @@ static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
  */
 static inline __wsum csum_and_copy_to_user(const void *src,
 					   void __user *dst,
-					   int len, __wsum sum,
-					   int *err_ptr)
+					   int len)
 {
 	__wsum ret;
+	int err = 0;
 
 	might_sleep();
-	if (user_access_begin(dst, len)) {
-		ret = csum_partial_copy_generic(src, (__force void *)dst,
-						len, sum, NULL, err_ptr);
-		user_access_end();
-		return ret;
-	}
+	if (!user_access_begin(dst, len))
+		return 0;
 
-	if (len)
-		*err_ptr = -EFAULT;
-
-	return (__force __wsum)-1; /* invalid checksum */
+	ret = csum_partial_copy_generic(src, (__force void *)dst,
+					len, ~0U, NULL, &err);
+	user_access_end();
+	return err ? 0 : ret;
 }
 
 #endif /* _ASM_X86_CHECKSUM_32_H */
diff --git a/arch/x86/include/asm/checksum_64.h b/arch/x86/include/asm/checksum_64.h
index 5339f5dfc776..9af3aed54c6b 100644
--- a/arch/x86/include/asm/checksum_64.h
+++ b/arch/x86/include/asm/checksum_64.h
@@ -135,10 +135,8 @@ extern __visible __wsum csum_partial_copy_generic(const void *src, const void *d
 					int *src_err_ptr, int *dst_err_ptr);
 
 
-extern __wsum csum_and_copy_from_user(const void __user *src, void *dst,
-					  int len, __wsum isum, int *errp);
-extern __wsum csum_and_copy_to_user(const void *src, void __user *dst,
-					int len, __wsum isum, int *errp);
+extern __wsum csum_and_copy_from_user(const void __user *src, void *dst, int len);
+extern __wsum csum_and_copy_to_user(const void *src, void __user *dst, int len);
 extern __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len);
 
 /**
diff --git a/arch/x86/lib/csum-wrappers_64.c b/arch/x86/lib/csum-wrappers_64.c
index 245f929a1c2c..ae2fb87e2274 100644
--- a/arch/x86/lib/csum-wrappers_64.c
+++ b/arch/x86/lib/csum-wrappers_64.c
@@ -22,13 +22,15 @@
  */
 __wsum
 csum_and_copy_from_user(const void __user *src, void *dst,
-			    int len, __wsum isum, int *errp)
+			    int len)
 {
+	int err = 0;
+	__wsum isum = ~0U;
+
 	might_sleep();
-	*errp = 0;
 
 	if (!user_access_begin(src, len))
-		goto out_err;
+		return 0;
 
 	/*
 	 * Why 6, not 7? To handle odd addresses aligned we
@@ -53,20 +55,15 @@ csum_and_copy_from_user(const void __user *src, void *dst,
 		}
 	}
 	isum = csum_partial_copy_generic((__force const void *)src,
-				dst, len, isum, errp, NULL);
+				dst, len, isum, &err, NULL);
 	user_access_end();
-	if (unlikely(*errp))
-		goto out_err;
-
+	if (unlikely(err))
+		isum = 0;
 	return isum;
 
 out:
 	user_access_end();
-out_err:
-	*errp = -EFAULT;
-	memset(dst, 0, len);
-
-	return isum;
+	return 0;
 }
 EXPORT_SYMBOL(csum_and_copy_from_user);
 
@@ -83,16 +80,15 @@ EXPORT_SYMBOL(csum_and_copy_from_user);
  */
 __wsum
 csum_and_copy_to_user(const void *src, void __user *dst,
-			  int len, __wsum isum, int *errp)
+			  int len)
 {
-	__wsum ret;
+	__wsum ret, isum = ~0U;
+	int err = 0;
 
 	might_sleep();
 
-	if (!user_access_begin(dst, len)) {
-		*errp = -EFAULT;
+	if (!user_access_begin(dst, len))
 		return 0;
-	}
 
 	if (unlikely((unsigned long)dst & 6)) {
 		while (((unsigned long)dst & 6) && len >= 2) {
@@ -107,15 +103,13 @@ csum_and_copy_to_user(const void *src, void __user *dst,
 		}
 	}
 
-	*errp = 0;
 	ret = csum_partial_copy_generic(src, (void __force *)dst,
-					len, isum, NULL, errp);
+					len, isum, NULL, &err);
 	user_access_end();
-	return ret;
+	return err ? 0 : ret;
 out:
 	user_access_end();
-	*errp = -EFAULT;
-	return isum;
+	return 0;
 }
 EXPORT_SYMBOL(csum_and_copy_to_user);
 
diff --git a/arch/x86/um/asm/checksum_32.h b/arch/x86/um/asm/checksum_32.h
index b9ac7c9eb72c..0b13c2947ad1 100644
--- a/arch/x86/um/asm/checksum_32.h
+++ b/arch/x86/um/asm/checksum_32.h
@@ -35,27 +35,4 @@ static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
 	return csum_fold(sum);
 }
 
-/*
- *	Copy and checksum to user
- */
-#define HAVE_CSUM_COPY_USER
-static __inline__ __wsum csum_and_copy_to_user(const void *src,
-						     void __user *dst,
-						     int len, __wsum sum, int *err_ptr)
-{
-	if (access_ok(dst, len)) {
-		if (copy_to_user(dst, src, len)) {
-			*err_ptr = -EFAULT;
-			return (__force __wsum)-1;
-		}
-
-		return csum_partial(src, len, sum);
-	}
-
-	if (len)
-		*err_ptr = -EFAULT;
-
-	return (__force __wsum)-1; /* invalid checksum */
-}
-
 #endif
diff --git a/arch/xtensa/include/asm/checksum.h b/arch/xtensa/include/asm/checksum.h
index dc09448935bf..fe78fba7bd64 100644
--- a/arch/xtensa/include/asm/checksum.h
+++ b/arch/xtensa/include/asm/checksum.h
@@ -55,14 +55,16 @@ __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
 static inline
 __wsum csum_and_copy_from_user(const void __user *src, void *dst,
-				   int len, __wsum sum, int *err_ptr)
+				   int len)
 {
-	if (access_ok(src, len))
-		return csum_partial_copy_generic((__force const void *)src, dst,
-					len, sum, err_ptr, NULL);
-	if (len)
-		*err_ptr = -EFAULT;
-	return sum;
+	int err = 0;
+
+	if (!access_ok(src, len))
+		return 0;
+
+	sum = csum_partial_copy_generic((__force const void *)src, dst,
+					len, ~0U, &err, NULL);
+	return err ? 0 : sum;
 }
 
 /*
@@ -243,15 +245,15 @@ static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
  */
 #define HAVE_CSUM_COPY_USER
 static __inline__ __wsum csum_and_copy_to_user(const void *src,
-					       void __user *dst, int len,
-					       __wsum sum, int *err_ptr)
+					       void __user *dst, int len)
 {
-	if (access_ok(dst, len))
-		return csum_partial_copy_generic(src,dst,len,sum,NULL,err_ptr);
+	int err = 0;
+	__wsum sum = ~0U;
 
-	if (len)
-		*err_ptr = -EFAULT;
+	if (!access_ok(dst, len))
+		return 0;
 
-	return (__force __wsum)-1; /* invalid checksum */
+	sum = csum_partial_copy_generic(src,dst,len,sum,NULL,&err);
+	return err ? 0 : sum;
 }
 #endif
diff --git a/include/net/checksum.h b/include/net/checksum.h
index 1029191986e3..0d05b9e8690b 100644
--- a/include/net/checksum.h
+++ b/include/net/checksum.h
@@ -24,26 +24,23 @@
 #ifndef _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
 static inline
 __wsum csum_and_copy_from_user (const void __user *src, void *dst,
-				      int len, __wsum sum, int *err_ptr)
+				      int len)
 {
 	if (copy_from_user(dst, src, len))
-		*err_ptr = -EFAULT;
-	return csum_partial(dst, len, sum);
+		return 0;
+	return csum_partial(dst, len, ~0U);
 }
 #endif
 
 #ifndef HAVE_CSUM_COPY_USER
 static __inline__ __wsum csum_and_copy_to_user
-(const void *src, void __user *dst, int len, __wsum sum, int *err_ptr)
+(const void *src, void __user *dst, int len)
 {
-	sum = csum_partial(src, len, sum);
+	__wsum sum = csum_partial(src, len, ~0U);
 
 	if (copy_to_user(dst, src, len) == 0)
 		return sum;
-	if (len)
-		*err_ptr = -EFAULT;
-
-	return (__force __wsum)-1; /* invalid checksum */
+	return 0;
 }
 #endif
 
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 437fbc14c972..ccb247faf79b 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -1449,15 +1449,14 @@ size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum,
 		return 0;
 	}
 	iterate_and_advance(i, bytes, v, ({
-		int err = 0;
 		next = csum_and_copy_from_user(v.iov_base,
 					       (to += v.iov_len) - v.iov_len,
-					       v.iov_len, ~0U, &err);
-		if (!err) {
+					       v.iov_len);
+		if (next) {
 			sum = csum_block_add(sum, next, off);
 			off += v.iov_len;
 		}
-		err ? v.iov_len : 0;
+		next ? 0 : v.iov_len;
 	}), ({
 		char *p = kmap_atomic(v.bv_page);
 		sum = csum_and_memcpy((to += v.bv_len) - v.bv_len,
@@ -1491,11 +1490,10 @@ bool csum_and_copy_from_iter_full(void *addr, size_t bytes, __wsum *csum,
 	if (unlikely(i->count < bytes))
 		return false;
 	iterate_all_kinds(i, bytes, v, ({
-		int err = 0;
 		next = csum_and_copy_from_user(v.iov_base,
 					       (to += v.iov_len) - v.iov_len,
-					       v.iov_len, ~0U, &err);
-		if (err)
+					       v.iov_len);
+		if (!next)
 			return false;
 		sum = csum_block_add(sum, next, off);
 		off += v.iov_len;
@@ -1537,15 +1535,14 @@ size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *csump,
 		return 0;
 	}
 	iterate_and_advance(i, bytes, v, ({
-		int err = 0;
 		next = csum_and_copy_to_user((from += v.iov_len) - v.iov_len,
 					     v.iov_base,
-					     v.iov_len, ~0U, &err);
-		if (!err) {
+					     v.iov_len);
+		if (next) {
 			sum = csum_block_add(sum, next, off);
 			off += v.iov_len;
 		}
-		err ? v.iov_len : 0;
+		next ? 0 : v.iov_len;
 	}), ({
 		char *p = kmap_atomic(v.bv_page);
 		sum = csum_and_memcpy(p + v.bv_offset,
-- 
cgit v1.2.3-59-g8ed1b


From b712139543af98a91300c4e923b85d311cc77c44 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Sun, 12 Jul 2020 22:55:27 -0400
Subject: alpha: propagate the calling convention changes down to
 csum_partial_copy.c helpers

get rid of set_fs() in csum_partial_copy_nocheck(), while we are at it -
just take the part of csum_and_copy_from_user() sans the access_ok() check
into a helper function and have csum_partial_copy_nocheck() call that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 arch/alpha/lib/csum_partial_copy.c | 157 ++++++++++++++++---------------------
 1 file changed, 69 insertions(+), 88 deletions(-)

(limited to 'arch/alpha')

diff --git a/arch/alpha/lib/csum_partial_copy.c b/arch/alpha/lib/csum_partial_copy.c
index 3c0e89c39ddb..dc68efbe9367 100644
--- a/arch/alpha/lib/csum_partial_copy.c
+++ b/arch/alpha/lib/csum_partial_copy.c
@@ -39,12 +39,11 @@ __asm__ __volatile__("insql %1,%2,%0":"=r" (z):"r" (x),"r" (y))
 #define insqh(x,y,z) \
 __asm__ __volatile__("insqh %1,%2,%0":"=r" (z):"r" (x),"r" (y))
 
-
-#define __get_user_u(x,ptr)				\
+#define __get_word(insn,x,ptr)				\
 ({							\
 	long __guu_err;					\
 	__asm__ __volatile__(				\
-	"1:	ldq_u %0,%2\n"				\
+	"1:	"#insn" %0,%2\n"			\
 	"2:\n"						\
 	EXC(1b,2b,%0,%1)				\
 		: "=r"(x), "=r"(__guu_err)		\
@@ -52,19 +51,6 @@ __asm__ __volatile__("insqh %1,%2,%0":"=r" (z):"r" (x),"r" (y))
 	__guu_err;					\
 })
 
-#define __put_user_u(x,ptr)				\
-({							\
-	long __puu_err;					\
-	__asm__ __volatile__(				\
-	"1:	stq_u %2,%1\n"				\
-	"2:\n"						\
-	EXC(1b,2b,$31,%0)				\
-		: "=r"(__puu_err)			\
-		: "m"(__m(addr)), "rJ"(x), "0"(0));	\
-	__puu_err;					\
-})
-
-
 static inline unsigned short from64to16(unsigned long x)
 {
 	/* Using extract instructions is a bit more efficient
@@ -95,15 +81,15 @@ static inline unsigned short from64to16(unsigned long x)
  */
 static inline unsigned long
 csum_partial_cfu_aligned(const unsigned long __user *src, unsigned long *dst,
-			 long len, unsigned long checksum,
-			 int *errp)
+			 long len)
 {
+	unsigned long checksum = ~0U;
 	unsigned long carry = 0;
-	int err = 0;
 
 	while (len >= 0) {
 		unsigned long word;
-		err |= __get_user(word, src);
+		if (__get_word(ldq, word, src))
+			return 0;
 		checksum += carry;
 		src++;
 		checksum += word;
@@ -116,7 +102,8 @@ csum_partial_cfu_aligned(const unsigned long __user *src, unsigned long *dst,
 	checksum += carry;
 	if (len) {
 		unsigned long word, tmp;
-		err |= __get_user(word, src);
+		if (__get_word(ldq, word, src))
+			return 0;
 		tmp = *dst;
 		mskql(word, len, word);
 		checksum += word;
@@ -125,7 +112,6 @@ csum_partial_cfu_aligned(const unsigned long __user *src, unsigned long *dst,
 		*dst = word | tmp;
 		checksum += carry;
 	}
-	if (err && errp) *errp = err;
 	return checksum;
 }
 
@@ -137,20 +123,21 @@ static inline unsigned long
 csum_partial_cfu_dest_aligned(const unsigned long __user *src,
 			      unsigned long *dst,
 			      unsigned long soff,
-			      long len, unsigned long checksum,
-			      int *errp)
+			      long len)
 {
 	unsigned long first;
 	unsigned long word, carry;
 	unsigned long lastsrc = 7+len+(unsigned long)src;
-	int err = 0;
+	unsigned long checksum = ~0U;
 
-	err |= __get_user_u(first,src);
+	if (__get_word(ldq_u, first,src))
+		return 0;
 	carry = 0;
 	while (len >= 0) {
 		unsigned long second;
 
-		err |= __get_user_u(second, src+1);
+		if (__get_word(ldq_u, second, src+1))
+			return 0;
 		extql(first, soff, word);
 		len -= 8;
 		src++;
@@ -168,7 +155,8 @@ csum_partial_cfu_dest_aligned(const unsigned long __user *src,
 	if (len) {
 		unsigned long tmp;
 		unsigned long second;
-		err |= __get_user_u(second, lastsrc);
+		if (__get_word(ldq_u, second, lastsrc))
+			return 0;
 		tmp = *dst;
 		extql(first, soff, word);
 		extqh(second, soff, first);
@@ -180,7 +168,6 @@ csum_partial_cfu_dest_aligned(const unsigned long __user *src,
 		*dst = word | tmp;
 		checksum += carry;
 	}
-	if (err && errp) *errp = err;
 	return checksum;
 }
 
@@ -191,18 +178,18 @@ static inline unsigned long
 csum_partial_cfu_src_aligned(const unsigned long __user *src,
 			     unsigned long *dst,
 			     unsigned long doff,
-			     long len, unsigned long checksum,
-			     unsigned long partial_dest,
-			     int *errp)
+			     long len,
+			     unsigned long partial_dest)
 {
 	unsigned long carry = 0;
 	unsigned long word;
 	unsigned long second_dest;
-	int err = 0;
+	unsigned long checksum = ~0U;
 
 	mskql(partial_dest, doff, partial_dest);
 	while (len >= 0) {
-		err |= __get_user(word, src);
+		if (__get_word(ldq, word, src))
+			return 0;
 		len -= 8;
 		insql(word, doff, second_dest);
 		checksum += carry;
@@ -216,7 +203,8 @@ csum_partial_cfu_src_aligned(const unsigned long __user *src,
 	len += 8;
 	if (len) {
 		checksum += carry;
-		err |= __get_user(word, src);
+		if (__get_word(ldq, word, src))
+			return 0;
 		mskql(word, len, word);
 		len -= 8;
 		checksum += word;
@@ -237,7 +225,6 @@ csum_partial_cfu_src_aligned(const unsigned long __user *src,
 	stq_u(partial_dest | second_dest, dst);
 out:
 	checksum += carry;
-	if (err && errp) *errp = err;
 	return checksum;
 }
 
@@ -249,23 +236,23 @@ static inline unsigned long
 csum_partial_cfu_unaligned(const unsigned long __user * src,
 			   unsigned long * dst,
 			   unsigned long soff, unsigned long doff,
-			   long len, unsigned long checksum,
-			   unsigned long partial_dest,
-			   int *errp)
+			   long len, unsigned long partial_dest)
 {
 	unsigned long carry = 0;
 	unsigned long first;
 	unsigned long lastsrc;
-	int err = 0;
+	unsigned long checksum = ~0U;
 
-	err |= __get_user_u(first, src);
+	if (__get_word(ldq_u, first, src))
+		return 0;
 	lastsrc = 7+len+(unsigned long)src;
 	mskql(partial_dest, doff, partial_dest);
 	while (len >= 0) {
 		unsigned long second, word;
 		unsigned long second_dest;
 
-		err |= __get_user_u(second, src+1);
+		if (__get_word(ldq_u, second, src+1))
+			return 0;
 		extql(first, soff, word);
 		checksum += carry;
 		len -= 8;
@@ -286,7 +273,8 @@ csum_partial_cfu_unaligned(const unsigned long __user * src,
 		unsigned long second, word;
 		unsigned long second_dest;
 
-		err |= __get_user_u(second, lastsrc);
+		if (__get_word(ldq_u, second, lastsrc))
+			return 0;
 		extql(first, soff, word);
 		extqh(second, soff, first);
 		word |= first;
@@ -307,7 +295,8 @@ csum_partial_cfu_unaligned(const unsigned long __user * src,
 		unsigned long second, word;
 		unsigned long second_dest;
 
-		err |= __get_user_u(second, lastsrc);
+		if (__get_word(ldq_u, second, lastsrc))
+			return 0;
 		extql(first, soff, word);
 		extqh(second, soff, first);
 		word |= first;
@@ -320,63 +309,55 @@ csum_partial_cfu_unaligned(const unsigned long __user * src,
 		stq_u(partial_dest | word | second_dest, dst);
 		checksum += carry;
 	}
-	if (err && errp) *errp = err;
 	return checksum;
 }
 
-__wsum
-csum_and_copy_from_user(const void __user *src, void *dst, int len)
+static __wsum __csum_and_copy(const void __user *src, void *dst, int len)
 {
-	unsigned long checksum = ~0U;
 	unsigned long soff = 7 & (unsigned long) src;
 	unsigned long doff = 7 & (unsigned long) dst;
-	int err = 0;
-
-	if (len) {
-		if (!access_ok(src, len))
-			return 0;
-		if (!doff) {
-			if (!soff)
-				checksum = csum_partial_cfu_aligned(
-					(const unsigned long __user *) src,
-					(unsigned long *) dst,
-					len-8, checksum, &err);
-			else
-				checksum = csum_partial_cfu_dest_aligned(
-					(const unsigned long __user *) src,
-					(unsigned long *) dst,
-					soff, len-8, checksum, &err);
-		} else {
-			unsigned long partial_dest;
-			ldq_u(partial_dest, dst);
-			if (!soff)
-				checksum = csum_partial_cfu_src_aligned(
-					(const unsigned long __user *) src,
-					(unsigned long *) dst,
-					doff, len-8, checksum,
-					partial_dest, &err);
-			else
-				checksum = csum_partial_cfu_unaligned(
-					(const unsigned long __user *) src,
-					(unsigned long *) dst,
-					soff, doff, len-8, checksum,
-					partial_dest, &err);
-		}
-		checksum = err ? 0 : from64to16 (checksum);
+	unsigned long checksum;
+
+	if (!doff) {
+		if (!soff)
+			checksum = csum_partial_cfu_aligned(
+				(const unsigned long __user *) src,
+				(unsigned long *) dst, len-8);
+		else
+			checksum = csum_partial_cfu_dest_aligned(
+				(const unsigned long __user *) src,
+				(unsigned long *) dst,
+				soff, len-8);
+	} else {
+		unsigned long partial_dest;
+		ldq_u(partial_dest, dst);
+		if (!soff)
+			checksum = csum_partial_cfu_src_aligned(
+				(const unsigned long __user *) src,
+				(unsigned long *) dst,
+				doff, len-8, partial_dest);
+		else
+			checksum = csum_partial_cfu_unaligned(
+				(const unsigned long __user *) src,
+				(unsigned long *) dst,
+				soff, doff, len-8, partial_dest);
 	}
-	return (__force __wsum)checksum;
+	return (__force __wsum)from64to16 (checksum);
+}
+
+__wsum
+csum_and_copy_from_user(const void __user *src, void *dst, int len)
+{
+	if (!access_ok(src, len))
+		return 0;
+	return __csum_and_copy(src, dst, len);
 }
 EXPORT_SYMBOL(csum_and_copy_from_user);
 
 __wsum
 csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
-	__wsum checksum;
-	mm_segment_t oldfs = get_fs();
-	set_fs(KERNEL_DS);
-	checksum = csum_and_copy_from_user((__force const void __user *)src,
+	return __csum_and_copy((__force const void __user *)src,
 						dst, len);
-	set_fs(oldfs);
-	return checksum;
 }
 EXPORT_SYMBOL(csum_partial_copy_nocheck);
-- 
cgit v1.2.3-59-g8ed1b