From: Yoshinori Sato <ysato@users.sourceforge.jp>
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: lkml <linux-kernel@vger.kernel.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
Andrew Morton <akpm@osdl.org>
Subject: Re: [RFC] breakage in 4223cc34365e4 (h8300: uaccess.h update)
Date: Mon, 10 Mar 2008 16:57:14 -0400 [thread overview]
Message-ID: <87fxuyz49h.wl%ysato@users.sourceforge.jp> (raw)
In-Reply-To: <20080302232314.GW27894@ZenIV.linux.org.uk>
At Sun, 2 Mar 2008 23:23:14 +0000,
Al Viro wrote:
>
> After that commit in asm-h8300/uaccess.h we have
>
> #define get_user(x, ptr) \
> ({ \
> int __gu_err = 0; \
> uint32_t __gu_val = 0; \
> ^^^^^^^^^^^^^^^^^
> switch (sizeof(*(ptr))) { \
> case 1: \
> case 2: \
> case 4: \
> __gu_val = *(ptr); \
> break; \
> case 8: \
> memcpy(&__gu_val, ptr, sizeof (*(ptr))); \
> ^^^^^^^^^^^^^^^^
>
> which, of course, is FUBAR whenever we actually hit that case - memcpy of
> 8 bytes into uint32_t is obviously wrong. Why don't we simply do
Oops.
>
> #define get_user(x, ptr) \
> ({ \
> int __gu_err = 0; \
> typeof(*(ptr)) __gu_val = *ptr; \
> switch (sizeof(*(ptr))) { \
> case 1: \
> case 2: \
> case 4: \
> case 8: \
> break; \
> default: \
> __gu_err = __get_user_bad(); \
> break; \
> } \
> (x) = __gu_val; \
> __gu_err; \
> })
>
> and be done with that, anyway?
Good! no problem.
Thank you.
Signed-off-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
include/asm-h8300/uaccess.h | 11 ++++-------
1 files changed, 4 insertions(+), 7 deletions(-)
diff --git a/include/asm-h8300/uaccess.h b/include/asm-h8300/uaccess.h
index a22350e..356068c 100644
--- a/include/asm-h8300/uaccess.h
+++ b/include/asm-h8300/uaccess.h
@@ -91,22 +91,19 @@ extern int __put_user_bad(void);
#define get_user(x, ptr) \
({ \
int __gu_err = 0; \
- uint32_t __gu_val = 0; \
+ typeof(*(ptr)) __gu_val = *ptr; \
switch (sizeof(*(ptr))) { \
case 1: \
case 2: \
case 4: \
- __gu_val = *(ptr); \
- break; \
- case 8: \
- memcpy(&__gu_val, ptr, sizeof (*(ptr))); \
+ case 8: \
break; \
default: \
- __gu_val = 0; \
__gu_err = __get_user_bad(); \
+ __gu_val = 0; \
break; \
} \
- (x) = (typeof(*(ptr)))__gu_val; \
+ (x) = __gu_val; \
__gu_err; \
})
#define __get_user(x, ptr) get_user(x, ptr)
--
1.5.4.3
--
Yoshinori Sato
<ysato@users.sourceforge.jp>
prev parent reply other threads:[~2008-03-10 20:57 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-03-02 23:23 [RFC] breakage in 4223cc34365e4 (h8300: uaccess.h update) Al Viro
2008-03-10 20:57 ` Yoshinori Sato [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87fxuyz49h.wl%ysato@users.sourceforge.jp \
--to=ysato@users.sourceforge.jp \
--cc=akpm@osdl.org \
--cc=linux-kernel@vger.kernel.org \
--cc=torvalds@linux-foundation.org \
--cc=viro@ZenIV.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.