leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

UAPI: fix endianness conditionals in linux/aio_abi.h

Browse Source 
In the UAPI header files, __BIG_ENDIAN and __LITTLE_ENDIAN must be
compared against __BYTE_ORDER in preprocessor conditionals where these are
exposed to userspace (that is they're not inside __KERNEL__ conditionals).

However, in the main kernel the norm is to check for
"defined(__XXX_ENDIAN)" rather than comparing against __BYTE_ORDER and
this has incorrectly leaked into the userspace headers.

The definition of PADDED() in linux/aio_abi.h is wrong in this way.  Note
that userspace will likely interpret this and thus the order of fields in
struct iocb incorrectly as the little-endian variant on big-endian
machines - depending on header inclusion order.

[!!!] NOTE [!!!]  This patch may adversely change the userspace API.  It might
be better to fix the ordering of aio_key and aio_reserved1 in struct iocb.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Benjamin LaHaise <bcrl@kvack.org>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Howells 2013-03-13 14:59:45 -07:00 committed by Linus Torvalds
parent 97da55fcec
commit 51b154ed52
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
include/uapi/linux/aio_abi.h
View File

@ -62,9 +62,9 @@ struct io_event {
__s64 res2; /* secondary result */
};
#if defined(__LITTLE_ENDIAN)
#if defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : defined(__LITTLE_ENDIAN)
#define PADDED(x,y) x, y
#elif defined(__BIG_ENDIAN)
#elif defined(__BYTE_ORDER) ? __BYTE_ORDER == __BIG_ENDIAN : defined(__BIG_ENDIAN)
#define PADDED(x,y) y, x
#else
#error edit for your odd byteorder.