Merge branch 'work.uaccess' into for-next

3 files changed, 30 insertions, 4 deletions

diff --git a/lib/Makefile b/lib/Makefile
index 320ac46a8725..b47cf97e1e68 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -41,7 +41,7 @@ obj-y += bcd.o div64.o sort.o parser.o debug_locks.o random32.o \
 	 gcd.o lcm.o list_sort.o uuid.o flex_array.o iov_iter.o clz_ctz.o \
 	 bsearch.o find_bit.o llist.o memweight.o kfifo.o \
 	 percpu-refcount.o percpu_ida.o rhashtable.o reciprocal_div.o \
-	 once.o refcount.o
+	 once.o refcount.o usercopy.o
 obj-y += string_helpers.o
 obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o
 obj-y += hexdump.o
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index e68604ae3ced..672c32f9f960 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -413,7 +413,7 @@ void iov_iter_init(struct iov_iter *i, int direction,
 			size_t count)
 {
 	/* It will get better.  Eventually... */
-	if (segment_eq(get_fs(), KERNEL_DS)) {
+	if (uaccess_kernel()) {
 		direction |= ITER_KVEC;
 		i->type = direction;
 		i->kvec = (struct kvec *)iov;
@@ -604,7 +604,7 @@ size_t copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i)
 		return 0;
 	}
 	iterate_and_advance(i, bytes, v,
-		__copy_from_user_nocache((to += v.iov_len) - v.iov_len,
+		__copy_from_user_inatomic_nocache((to += v.iov_len) - v.iov_len,
 					 v.iov_base, v.iov_len),
 		memcpy_from_page((to += v.bv_len) - v.bv_len, v.bv_page,
 				 v.bv_offset, v.bv_len),
@@ -625,7 +625,7 @@ bool copy_from_iter_full_nocache(void *addr, size_t bytes, struct iov_iter *i)
 	if (unlikely(i->count < bytes))
 		return false;
 	iterate_all_kinds(i, bytes, v, ({
-		if (__copy_from_user_nocache((to += v.iov_len) - v.iov_len,
+		if (__copy_from_user_inatomic_nocache((to += v.iov_len) - v.iov_len,
 					     v.iov_base, v.iov_len))
 			return false;
 		0;}),
diff --git a/lib/usercopy.c b/lib/usercopy.c
new file mode 100644
index 000000000000..1b6010a3beb8
--- /dev/null
+++ b/lib/usercopy.c
@@ -0,0 +1,26 @@
+#include <linux/uaccess.h>
+
+/* out-of-line parts */
+
+#ifndef INLINE_COPY_FROM_USER
+unsigned long _copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+	unsigned long res = n;
+	if (likely(access_ok(VERIFY_READ, from, n)))
+		res = raw_copy_from_user(to, from, n);
+	if (unlikely(res))
+		memset(to + (n - res), 0, res);
+	return res;
+}
+EXPORT_SYMBOL(_copy_from_user);
+#endif
+
+#ifndef INLINE_COPY_TO_USER
+unsigned long _copy_to_user(void *to, const void __user *from, unsigned long n)
+{
+	if (likely(access_ok(VERIFY_WRITE, to, n)))
+		n = raw_copy_to_user(to, from, n);
+	return n;
+}
+EXPORT_SYMBOL(_copy_to_user);
+#endif