Re: [PATCH 1/6] syscalls: use uaccess_kernel in addr_limit_user_check

From: Christoph Hellwig
Date: Sat Jul 18 2020 - 05:48:52 EST


On Fri, Jul 17, 2020 at 06:38:50PM -0700, Guenter Roeck wrote:
> Hi,
>
> On Tue, Jul 14, 2020 at 12:55:00PM +0200, Christoph Hellwig wrote:
> > Use the uaccess_kernel helper instead of duplicating it.
> >
> > Signed-off-by: Christoph Hellwig <hch@xxxxxx>
>
> This patch causes a severe hiccup with my mps2-an385 boot test.

I guess that is a nommu config?

Can you try this patch?

diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h
index b19c9bec1f7a63..cc7daf374a6eb6 100644
--- a/arch/arm/include/asm/uaccess.h
+++ b/arch/arm/include/asm/uaccess.h
@@ -263,7 +263,7 @@ extern int __put_user_8(void *, unsigned long long);
*/
#define USER_DS KERNEL_DS

-#define uaccess_kernel() (true)
+#define uaccess_kernel() (false)
#define __addr_ok(addr) ((void)(addr), 1)
#define __range_ok(addr, size) ((void)(addr), 0)
#define get_fs() (KERNEL_DS)