[PATCH v2 1/5] microblaze: uaccess: Zero out destination on failed get_user()

[Thomas Weißschuh]

On failure get_user() is supposed to zero out the destination variable.
This is documented in the kdoc of the microblaze get_user()
implementation and validated in lib/tests/usercopy_kunit.c.

Currently that zeroing is missing.

Add it.

Fixes: 0d6de9532663 ("microblaze_mmu_v2: uaccess MMU update")
Signed-off-by: Thomas Weißschuh <li...@weissschuh.net>
Reviewed-by: David Gow <da...@davidgow.net>
---
arch/microblaze/include/asm/uaccess.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h
index afa0dd8d013f..77203af255e5 100644
--- a/arch/microblaze/include/asm/uaccess.h
+++ b/arch/microblaze/include/asm/uaccess.h
@@ -95,7 +95,8 @@ extern long __user_bad(void);
#define get_user(x, ptr) ({ \
const typeof(*(ptr)) __user *__gu_ptr = (ptr); \
access_ok(__gu_ptr, sizeof(*__gu_ptr)) ? \
- __get_user(x, __gu_ptr) : -EFAULT; \
+ __get_user(x, __gu_ptr) : \
+ ((x) = 0, -EFAULT); \
})

#define __get_user(x, ptr) \

--
2.55.0