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| author | David Howells <dhowells@redhat.com> | 2013-03-14 01:59:47 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-03-14 02:21:49 +0400 |
| commit | ca044f9a9ed492f0f7e52df999c10ca6f7cfc5c0 (patch) | |
| tree | 0693ff6fd14f52d164a98d593ee1dcf639cff5fc | |
| parent | 29ba06b9ed51d49dea6c79c3c16b961d661262bd (diff) | |
| download | linux-ca044f9a9ed492f0f7e52df999c10ca6f7cfc5c0.tar.xz | |
UAPI: fix endianness conditionals in linux/raid/md_p.h
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 mdp_superblock_s in linux/raid/md_p.h is wrong in
this way. Note that userspace will likely interpret the ordering of the
fields incorrectly as the big-endian variant on a 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 events_hi, events_lo, cp_events_hi and
cp_events_lo in struct mdp_superblock_s / typedef mdp_super_t.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/uapi/linux/raid/md_p.h | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/include/uapi/linux/raid/md_p.h b/include/uapi/linux/raid/md_p.h index ee753536ab70..fe1a5406d4d9 100644 --- a/include/uapi/linux/raid/md_p.h +++ b/include/uapi/linux/raid/md_p.h @@ -145,16 +145,18 @@ typedef struct mdp_superblock_s { __u32 failed_disks; /* 4 Number of failed disks */ __u32 spare_disks; /* 5 Number of spare disks */ __u32 sb_csum; /* 6 checksum of the whole superblock */ -#ifdef __BIG_ENDIAN +#if defined(__BYTE_ORDER) ? __BYTE_ORDER == __BIG_ENDIAN : defined(__BIG_ENDIAN) __u32 events_hi; /* 7 high-order of superblock update count */ __u32 events_lo; /* 8 low-order of superblock update count */ __u32 cp_events_hi; /* 9 high-order of checkpoint update count */ __u32 cp_events_lo; /* 10 low-order of checkpoint update count */ -#else +#elif defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : defined(__LITTLE_ENDIAN) __u32 events_lo; /* 7 low-order of superblock update count */ __u32 events_hi; /* 8 high-order of superblock update count */ __u32 cp_events_lo; /* 9 low-order of checkpoint update count */ __u32 cp_events_hi; /* 10 high-order of checkpoint update count */ +#else +#error unspecified endianness #endif __u32 recovery_cp; /* 11 recovery checkpoint sector count */ /* There are only valid for minor_version > 90 */ |