Re: [PATCH] RISC-V: Fix raw_copy_{to,from}_user()

From: Palmer Dabbelt
Date: Thu Nov 15 2018 - 09:59:09 EST


On Wed, 14 Nov 2018 16:27:55 PST (-0800), Olof Johansson wrote:
Sparse highlighted it, and appears to be a pure bug (from vs to).

./arch/riscv/include/asm/uaccess.h:403:35: warning: incorrect type in argument 1 (different address spaces)
./arch/riscv/include/asm/uaccess.h:403:39: warning: incorrect type in argument 2 (different address spaces)
./arch/riscv/include/asm/uaccess.h:409:37: warning: incorrect type in argument 1 (different address spaces)
./arch/riscv/include/asm/uaccess.h:409:41: warning: incorrect type in argument 2 (different address spaces)

Signed-off-by: Olof Johansson <olof@xxxxxxxxx>
---
arch/riscv/include/asm/uaccess.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/include/asm/uaccess.h b/arch/riscv/include/asm/uaccess.h
index 473cfc84e412f..8c3e3e3c8be12 100644
--- a/arch/riscv/include/asm/uaccess.h
+++ b/arch/riscv/include/asm/uaccess.h
@@ -400,13 +400,13 @@ extern unsigned long __must_check __asm_copy_from_user(void *to,
static inline unsigned long
raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
- return __asm_copy_to_user(to, from, n);
+ return __asm_copy_from_user(to, from, n);
}

static inline unsigned long
raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
- return __asm_copy_from_user(to, from, n);
+ return __asm_copy_to_user(to, from, n);
}

extern long strncpy_from_user(char *dest, const char __user *src, long count);

Oh, no idea how I missed that one. This looks like it's been in for a long time, so I'm surprised anything works at all!

I'm going to add a stable CC and PR this to Linus this week, assuming I get some time to at least give it a minimal test.

Thanks for catching this!