linux-kernel - [PATCH] asm-generic: Force cast get

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Date:   Fri, 17 Feb 2017 08:52:29 -0800
From:   Stephen Boyd <stephen.boyd@...aro.org>
To:     Arnd Bergmann <arnd@...db.de>
Cc:     linux-kernel@...r.kernel.org, linux-arch@...r.kernel.org
Subject: [PATCH] asm-generic: Force cast get_user() setting x to 0

If we call get_user() with an __le* or __be* type sparse will
complain when we assign the result to 0 on the faulting path.
Let's force cast here so that sparse doesn't complain. This
mirrors what we do in __get_user() as well.

Signed-off-by: Stephen Boyd <stephen.boyd@...aro.org>
---

I made a similar fix to arm64 headers, and it looks like asm-generic
would need the same fix.

 include/asm-generic/uaccess.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/asm-generic/uaccess.h b/include/asm-generic/uaccess.h
index cc6bb319e464..6352d61df7eb 100644
--- a/include/asm-generic/uaccess.h
+++ b/include/asm-generic/uaccess.h
@@ -227,7 +227,7 @@ extern int __put_user_bad(void) __attribute__((noreturn));
 	might_fault();						\
 	access_ok(VERIFY_READ, __p, sizeof(*ptr)) ?		\
 		__get_user((x), (__typeof__(*(ptr)) *)__p) :	\
-		((x) = (__typeof__(*(ptr)))0,-EFAULT);		\
+		((x) = (__force __typeof__(*(ptr)))0, -EFAULT);	\
 })
 
 #ifndef __get_user_fn
-- 
2.10.0.297.gf6727b0