* [PATCH 0/2] fix missing handling of __user in nommu's uaccess()
@ 2020-05-28 20:25 Luc Van Oostenryck
2020-05-28 20:25 ` [PATCH 1/2] m68k,nommu: add missing __user in uaccess' __ptr() macro Luc Van Oostenryck
2020-05-28 20:25 ` [PATCH 2/2] m68k,nommu: fix implicit cast from __user in __{get,put}_user_asm() Luc Van Oostenryck
0 siblings, 2 replies; 4+ messages in thread
From: Luc Van Oostenryck @ 2020-05-28 20:25 UTC (permalink / raw)
To: Geert Uytterhoeven, Greg Ungerer
Cc: linux-m68k, linux-kernel, Luc Van Oostenryck
I received a bug report for an unrelated patch when used with m68k-nommu.
It appears that the origin of the problem is that __get_user() and
__put_user() doesn't handle correctly __user. These 2 patches fix this.
Note: this is only minimaly tested but is quite straightforward and
since this only change __user annotation it will not change the
generated code.
Luc Van Oostenryck (2):
m68k,nommu: add missing __user in uaccess' __ptr() macro
m68k,nommu: fix implicit cast from __user in __{get,put}_user_asm()
arch/m68k/include/asm/uaccess_no.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH 1/2] m68k,nommu: add missing __user in uaccess' __ptr() macro
2020-05-28 20:25 [PATCH 0/2] fix missing handling of __user in nommu's uaccess() Luc Van Oostenryck
@ 2020-05-28 20:25 ` Luc Van Oostenryck
2020-05-28 20:25 ` [PATCH 2/2] m68k,nommu: fix implicit cast from __user in __{get,put}_user_asm() Luc Van Oostenryck
1 sibling, 0 replies; 4+ messages in thread
From: Luc Van Oostenryck @ 2020-05-28 20:25 UTC (permalink / raw)
To: Geert Uytterhoeven, Greg Ungerer
Cc: linux-m68k, linux-kernel, Luc Van Oostenryck, kbuild test robot
The assembly for __get_user() & __put_user() uses a macro, __ptr(),
to cast the pointer to 'unsigned long *' but the pointer is always
a __user one and so this cast creates a lot of warnings when using
Sparse.
So, change to the cast to 'unsigned long __user *'.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
---
arch/m68k/include/asm/uaccess_no.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/m68k/include/asm/uaccess_no.h b/arch/m68k/include/asm/uaccess_no.h
index a24cfe4a0d32..9651766a62af 100644
--- a/arch/m68k/include/asm/uaccess_no.h
+++ b/arch/m68k/include/asm/uaccess_no.h
@@ -60,7 +60,7 @@ extern int __put_user_bad(void);
* aliasing issues.
*/
-#define __ptr(x) ((unsigned long *)(x))
+#define __ptr(x) ((unsigned long __user *)(x))
#define __put_user_asm(err,x,ptr,bwl) \
__asm__ ("move" #bwl " %0,%1" \
--
2.26.2
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH 2/2] m68k,nommu: fix implicit cast from __user in __{get,put}_user_asm()
2020-05-28 20:25 [PATCH 0/2] fix missing handling of __user in nommu's uaccess() Luc Van Oostenryck
2020-05-28 20:25 ` [PATCH 1/2] m68k,nommu: add missing __user in uaccess' __ptr() macro Luc Van Oostenryck
@ 2020-05-28 20:25 ` Luc Van Oostenryck
2020-05-29 13:21 ` Greg Ungerer
1 sibling, 1 reply; 4+ messages in thread
From: Luc Van Oostenryck @ 2020-05-28 20:25 UTC (permalink / raw)
To: Geert Uytterhoeven, Greg Ungerer
Cc: linux-m68k, linux-kernel, Luc Van Oostenryck, kbuild test robot
The assembly for __get_user_asm() & __put_user_asm() uses memcpy()
when the size is 8.
However, the pointer is always a __user one while memcpy() expect
a plan one and so this cast creates a lot of warnings when using
Sparse.
So, fix this by adding a cast to 'void __force *' at memcpy()'s
argument.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
---
arch/m68k/include/asm/uaccess_no.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/m68k/include/asm/uaccess_no.h b/arch/m68k/include/asm/uaccess_no.h
index 9651766a62af..f32f08a64eaa 100644
--- a/arch/m68k/include/asm/uaccess_no.h
+++ b/arch/m68k/include/asm/uaccess_no.h
@@ -42,7 +42,7 @@ static inline int _access_ok(unsigned long addr, unsigned long size)
__put_user_asm(__pu_err, __pu_val, ptr, l); \
break; \
case 8: \
- memcpy(ptr, &__pu_val, sizeof (*(ptr))); \
+ memcpy((void __force*)ptr, &__pu_val, sizeof (*(ptr))); \
break; \
default: \
__pu_err = __put_user_bad(); \
@@ -85,7 +85,7 @@ extern int __put_user_bad(void);
u64 l; \
__typeof__(*(ptr)) t; \
} __gu_val; \
- memcpy(&__gu_val.l, ptr, sizeof(__gu_val.l)); \
+ memcpy(&__gu_val.l, (const void __force*)ptr, sizeof(__gu_val.l)); \
(x) = __gu_val.t; \
break; \
} \
--
2.26.2
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 2/2] m68k,nommu: fix implicit cast from __user in __{get,put}_user_asm()
2020-05-28 20:25 ` [PATCH 2/2] m68k,nommu: fix implicit cast from __user in __{get,put}_user_asm() Luc Van Oostenryck
@ 2020-05-29 13:21 ` Greg Ungerer
0 siblings, 0 replies; 4+ messages in thread
From: Greg Ungerer @ 2020-05-29 13:21 UTC (permalink / raw)
To: Luc Van Oostenryck, Geert Uytterhoeven
Cc: linux-m68k, linux-kernel, kbuild test robot
Hi Luc,
On 29/5/20 6:25 am, Luc Van Oostenryck wrote:
> The assembly for __get_user_asm() & __put_user_asm() uses memcpy()
> when the size is 8.
>
> However, the pointer is always a __user one while memcpy() expect
> a plan one and so this cast creates a lot of warnings when using ^^^^
Did you mean "plain"?
> Sparse.
>
> So, fix this by adding a cast to 'void __force *' at memcpy()'s
> argument.
>
> Reported-by: kbuild test robot <lkp@intel.com>
> Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
> ---
> arch/m68k/include/asm/uaccess_no.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/m68k/include/asm/uaccess_no.h b/arch/m68k/include/asm/uaccess_no.h
> index 9651766a62af..f32f08a64eaa 100644
> --- a/arch/m68k/include/asm/uaccess_no.h
> +++ b/arch/m68k/include/asm/uaccess_no.h
> @@ -42,7 +42,7 @@ static inline int _access_ok(unsigned long addr, unsigned long size)
> __put_user_asm(__pu_err, __pu_val, ptr, l); \
> break; \
> case 8: \
> - memcpy(ptr, &__pu_val, sizeof (*(ptr))); \
> + memcpy((void __force*)ptr, &__pu_val, sizeof (*(ptr))); \
^^^
checkpatch wants a ' ' space in there.
Otherwise I think it looks good.
Regards
Greg
> break; \
> default: \
> __pu_err = __put_user_bad(); \
> @@ -85,7 +85,7 @@ extern int __put_user_bad(void);
> u64 l; \
> __typeof__(*(ptr)) t; \
> } __gu_val; \
> - memcpy(&__gu_val.l, ptr, sizeof(__gu_val.l)); \
> + memcpy(&__gu_val.l, (const void __force*)ptr, sizeof(__gu_val.l)); \
> (x) = __gu_val.t; \
> break; \
> } \
>
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2020-05-29 13:21 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2020-05-28 20:25 [PATCH 0/2] fix missing handling of __user in nommu's uaccess() Luc Van Oostenryck
2020-05-28 20:25 ` [PATCH 1/2] m68k,nommu: add missing __user in uaccess' __ptr() macro Luc Van Oostenryck
2020-05-28 20:25 ` [PATCH 2/2] m68k,nommu: fix implicit cast from __user in __{get,put}_user_asm() Luc Van Oostenryck
2020-05-29 13:21 ` Greg Ungerer
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