Re: [RFC][PATCH 05/14] ia64: csum_partial_copy_nocheck(): don't abuse csum_partial_copy_from_user()

Re: [RFC][PATCH 05/14] ia64: csum_partial_copy_nocheck(): don't abuse csum_partial_copy_from_user()

[Guenter Roeck]

On Wed, Jun 03, 2020 at 08:10:38PM +0100, Al Viro wrote:
> On Wed, Jun 03, 2020 at 08:37:14AM -0700, Guenter Roeck wrote:
> > On Fri, Mar 27, 2020 at 11:31:08PM +0000, Al Viro wrote:
> > > From: Al Viro <viro@zeniv.linux.org.uk>
> > > 
> > > Just inline the call and use memcpy() instead of __copy_from_user() and
> > > note that the tail is precisely ia64 csum_partial().
> > > 
> > > Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
> > 
> > This patch results in:
> > 
> > arch/ia64/lib/csum_partial_copy.c: In function 'csum_partial_copy_nocheck':
> > arch/ia64/lib/csum_partial_copy.c:110:9: error: implicit declaration of function 'csum_partial'
> > 
> > for ia64:{defconfig, allnoconfig, tinyconfig}.
> 
> Argh...
> 
> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Yes, that does the trick.

Tested-by: Guenter Roeck <linux@roeck-us.net>

> ---
> diff --git a/arch/ia64/lib/csum_partial_copy.c b/arch/ia64/lib/csum_partial_copy.c
> index 5d147a33d648..6e82e0be8040 100644
> --- a/arch/ia64/lib/csum_partial_copy.c
> +++ b/arch/ia64/lib/csum_partial_copy.c
> @@ -12,7 +12,7 @@
>  #include <linux/types.h>
>  #include <linux/string.h>
>  
> -#include <linux/uaccess.h>
> +#include <net/checksum.h>
>  
>  /*
>   * XXX Fixme: those 2 inlines are meant for debugging and will go away

Re: [RFC][PATCH 05/14] ia64: csum_partial_copy_nocheck(): don't abuse csum_partial_copy_from_user()

[Al Viro]

On Wed, Jun 03, 2020 at 08:37:14AM -0700, Guenter Roeck wrote:
> On Fri, Mar 27, 2020 at 11:31:08PM +0000, Al Viro wrote:
> > From: Al Viro <viro@zeniv.linux.org.uk>
> > 
> > Just inline the call and use memcpy() instead of __copy_from_user() and
> > note that the tail is precisely ia64 csum_partial().
> > 
> > Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
> 
> This patch results in:
> 
> arch/ia64/lib/csum_partial_copy.c: In function 'csum_partial_copy_nocheck':
> arch/ia64/lib/csum_partial_copy.c:110:9: error: implicit declaration of function 'csum_partial'
> 
> for ia64:{defconfig, allnoconfig, tinyconfig}.

Argh...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
diff --git a/arch/ia64/lib/csum_partial_copy.c b/arch/ia64/lib/csum_partial_copy.c
index 5d147a33d648..6e82e0be8040 100644
--- a/arch/ia64/lib/csum_partial_copy.c
+++ b/arch/ia64/lib/csum_partial_copy.c
@@ -12,7 +12,7 @@
 #include <linux/types.h>
 #include <linux/string.h>
 
-#include <linux/uaccess.h>
+#include <net/checksum.h>
 
 /*
  * XXX Fixme: those 2 inlines are meant for debugging and will go away

Re: [RFC][PATCH 05/14] ia64: csum_partial_copy_nocheck(): don't abuse csum_partial_copy_from_user()

[Guenter Roeck]

On Fri, Mar 27, 2020 at 11:31:08PM +0000, Al Viro wrote:
> From: Al Viro <viro@zeniv.linux.org.uk>
> 
> Just inline the call and use memcpy() instead of __copy_from_user() and
> note that the tail is precisely ia64 csum_partial().
> 
> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

This patch results in:

arch/ia64/lib/csum_partial_copy.c: In function 'csum_partial_copy_nocheck':
arch/ia64/lib/csum_partial_copy.c:110:9: error: implicit declaration of function 'csum_partial'

for ia64:{defconfig, allnoconfig, tinyconfig}.

Guenter

---
# bad: [d6f9469a03d832dcd17041ed67774ffb5f3e73b3] Merge tag 'erofs-for-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs
# good: [b23c4771ff62de8ca9b5e4a2d64491b2fb6f8f69] Merge tag 'docs-5.8' of git://git.lwn.net/linux
git bisect start 'HEAD' 'b23c4771ff62'
# good: [6cf991611bc72c077f0cc64e23987341ad7ef41e] Merge tag 'drm-intel-next-2020-05-15' of git://anongit.freedesktop.org/drm/drm-intel into drm-next
git bisect good 6cf991611bc72c077f0cc64e23987341ad7ef41e
# bad: [faa392181a0bd42c5478175cef601adeecdc91b6] Merge tag 'drm-next-2020-06-02' of git://anongit.freedesktop.org/drm/drm
git bisect bad faa392181a0bd42c5478175cef601adeecdc91b6
# bad: [c5d6c13843880ad0112f0513f3eb041b258be66e] Merge tag 'mmc-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc
git bisect bad c5d6c13843880ad0112f0513f3eb041b258be66e
# bad: [94709049fb8442fb2f7b91fbec3c2897a75e18df] Merge branch 'akpm' (patches from Andrew)
git bisect bad 94709049fb8442fb2f7b91fbec3c2897a75e18df
# good: [a29adb6209cead1f6c34a8d72481fb183bfc2d68] mm: rename vmap_page_range to map_kernel_range
git bisect good a29adb6209cead1f6c34a8d72481fb183bfc2d68
# bad: [56446efab9ce4961fe0fe6bbc5bc66374b08b9f3] Merge branch 'uaccess.__copy_from_user' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
git bisect bad 56446efab9ce4961fe0fe6bbc5bc66374b08b9f3
# good: [87c233b8158a20a9c9ab1da96cb5cb1734d9006e] vmci_host: get rid of pointless access_ok()
git bisect good 87c233b8158a20a9c9ab1da96cb5cb1734d9006e
# bad: [001c1a655f0a4e4ebe5d9beb47466dc5c6ab4871] default csum_and_copy_to_user(): don't bother with access_ok()
git bisect bad 001c1a655f0a4e4ebe5d9beb47466dc5c6ab4871
# bad: [808b49da54e640cba5c5c92dee658018a529226b] alpha: turn csum_partial_copy_from_user() into csum_and_copy_from_user()
git bisect bad 808b49da54e640cba5c5c92dee658018a529226b
# good: [0a5ea224b2fdf9dca9291ef7b5a12fd846a5dc34] x86: switch both 32bit and 64bit to providing csum_and_copy_from_user()
git bisect good 0a5ea224b2fdf9dca9291ef7b5a12fd846a5dc34
# bad: [cc03f19cfd45f44a75f0445c5be0073bbd3dda1c] ia64: csum_partial_copy_nocheck(): don't abuse csum_partial_copy_from_user()
git bisect bad cc03f19cfd45f44a75f0445c5be0073bbd3dda1c
# good: [c281a6c1ac6b0867e4341ea801030fa9a62157f9] x86: switch 32bit csum_and_copy_to_user() to user_access_{begin,end}()
git bisect good c281a6c1ac6b0867e4341ea801030fa9a62157f9
# first bad commit: [cc03f19cfd45f44a75f0445c5be0073bbd3dda1c] ia64: csum_partial_copy_nocheck(): don't abuse csum_partial_copy_from_user()

[RFC][PATCH 05/14] ia64: csum_partial_copy_nocheck(): don't abuse csum_partial_copy_from_user()

[Al Viro]

From: Al Viro <viro@zeniv.linux.org.uk>

Just inline the call and use memcpy() instead of __copy_from_user() and
note that the tail is precisely ia64 csum_partial().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 arch/ia64/lib/csum_partial_copy.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/ia64/lib/csum_partial_copy.c b/arch/ia64/lib/csum_partial_copy.c
index bf9396b1ed32..9ab570d0f756 100644
--- a/arch/ia64/lib/csum_partial_copy.c
+++ b/arch/ia64/lib/csum_partial_copy.c
@@ -134,8 +134,8 @@ EXPORT_SYMBOL(csum_partial_copy_from_user);
 __wsum
 csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
 {
-	return csum_partial_copy_from_user((__force const void __user *)src,
-					   dst, len, sum, NULL);
+	memcpy(dst, src, len);
+	return csum_partial(dst, len, sum);
 }
 
 EXPORT_SYMBOL(csum_partial_copy_nocheck);
-- 
2.11.0