Add an x86 implementation of unsafe_copy_from_user() similar to the
existing unsafe_copy_to_user().
Signed-off-by: Josh Poimboeuf <jpoim...@kernel.org>
---
arch/x86/include/asm/uaccess.h | 39 +++++++++++++++++++++++++---------
1 file changed, 29 insertions(+), 10 deletions(-)
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index 3a7755c1a441..a3148865bc57 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -599,23 +599,42 @@ _label:
\
* We want the unsafe accessors to always be inlined and use
* the error labels - thus the macro games.
*/
-#define unsafe_copy_loop(dst, src, len, type, label)
\
+#define unsafe_copy_to_user_loop(dst, src, len, type, label)
\
while (len >= sizeof(type)) {
\
- unsafe_put_user(*(type *)(src),(type __user *)(dst),label);
\
+ unsafe_put_user(*(type *)(src), (type __user *)(dst), label);
\
dst += sizeof(type);
\
src += sizeof(type);
\
len -= sizeof(type);
\
}
-#define unsafe_copy_to_user(_dst,_src,_len,label) \
+#define unsafe_copy_to_user(_dst, _src, _len, label) \
do { \
- char __user *__ucu_dst = (_dst); \
- const char *__ucu_src = (_src); \
- size_t __ucu_len = (_len); \
- unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u64, label); \
- unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u32, label); \
- unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u16, label); \
- unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u8, label); \
+ void __user *__dst = (_dst); \
+ const void *__src = (_src); \
+ size_t __len = (_len); \
+ unsafe_copy_to_user_loop(__dst, __src, __len, u64, label); \
+ unsafe_copy_to_user_loop(__dst, __src, __len, u32, label); \
+ unsafe_copy_to_user_loop(__dst, __src, __len, u16, label); \
+ unsafe_copy_to_user_loop(__dst, __src, __len, u8, label); \
+} while (0)
+
+#define unsafe_copy_from_user_loop(dst, src, len, type, label)
\
+ while (len >= sizeof(type)) {
\
+ unsafe_get_user(*(type *)(dst),(type __user *)(src),label);
\
+ dst += sizeof(type);
\
+ src += sizeof(type);
\
+ len -= sizeof(type);
\
+ }
+
+#define unsafe_copy_from_user(_dst, _src, _len, label) \
+do { \
+ void *__dst = (_dst); \
+ void __user *__src = (_src); \
+ size_t __len = (_len); \
+ unsafe_copy_from_user_loop(__dst, __src, __len, u64, label); \
+ unsafe_copy_from_user_loop(__dst, __src, __len, u32, label); \
+ unsafe_copy_from_user_loop(__dst, __src, __len, u16, label); \
+ unsafe_copy_from_user_loop(__dst, __src, __len, u8, label); \
} while (0)
#ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
--
2.48.1
