UAPI: fix endianness conditionals in M32R's asm/stat.h
authorDavid Howells <dhowells@redhat.com>
Wed, 13 Mar 2013 21:59:48 +0000 (14:59 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 13 Mar 2013 22:21:49 +0000 (15:21 -0700)
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 struct stat64 in M32R's asm/stat.h is wrong in this way.
 Note that userspace will likely interpret the field order incorrectly as
the big-endian variant on little-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 st_blocks and __pad4 in struct stat64.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/m32r/include/uapi/asm/stat.h

index da4518f82d6d31d71609d7a670924cbe79c88c2a..98470fe483b67861b952f7c35bb946111016c9db 100644 (file)
@@ -63,10 +63,10 @@ struct stat64 {
        long long       st_size;
        unsigned long   st_blksize;
 
-#if defined(__BIG_ENDIAN)
+#if defined(__BYTE_ORDER) ? __BYTE_ORDER == __BIG_ENDIAN : defined(__BIG_ENDIAN)
        unsigned long   __pad4;         /* future possible st_blocks high bits */
        unsigned long   st_blocks;      /* Number 512-byte blocks allocated. */
-#elif defined(__LITTLE_ENDIAN)
+#elif defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : defined(__LITTLE_ENDIAN)
        unsigned long   st_blocks;      /* Number 512-byte blocks allocated. */
        unsigned long   __pad4;         /* future possible st_blocks high bits */
 #else