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| author | Nick Bowler <nbowler@draconx.ca> | 2018-12-17 18:35:27 +0100 |
|---|---|---|
| committer | Darrick J. Wong <darrick.wong@oracle.com> | 2018-12-18 19:55:21 +0100 |
| commit | a9d25bde1e9b24161dd798e1d23eb7eb9674012a (patch) | |
| tree | 798d03905e89ad49e0a22c0ff7d2f9344983a2ff | |
| parent | xfs: Fix bulkstat compat ioctls on x32 userspace. (diff) | |
| download | linux-a9d25bde1e9b24161dd798e1d23eb7eb9674012a.tar.xz linux-a9d25bde1e9b24161dd798e1d23eb7eb9674012a.zip | |
xfs: Fix x32 ioctls when cmd numbers differ from ia32.
Several ioctl structs change size between native 32-bit (ia32) and x32
applications, because x32 follows the native 64-bit (amd64) integer
alignment rules and uses 64-bit time_t. In these instances, the ioctl
number changes so userspace simply gets -ENOTTY. This scenario can be
handled by simply adding more cases.
Looking at the different ioctls implemented here:
- All the ones marked 'No size or alignment issue on any arch' should
presumably all be fine.
- All the ones under BROKEN_X86_ALIGNMENT are different under integer
alignment rules. Since x32 matches amd64 here, we just need both
sets of cases handled.
- XFS_IOC_SWAPEXT has both integer alignment differences and time_t
differences. Since x32 matches amd64 here, we need to add a case
which calls the native implementation.
- The remaining ioctls have neither 64-bit integers nor time_t, so
x32 matches ia32 here and no change is required at this level. The
bulkstat ioctl implementations have some pointer chasing which is
handled separately.
Signed-off-by: Nick Bowler <nbowler@draconx.ca>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
| -rw-r--r-- | fs/xfs/xfs_ioctl32.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c index b044f7d36782..5001dca361e9 100644 --- a/fs/xfs/xfs_ioctl32.c +++ b/fs/xfs/xfs_ioctl32.c @@ -579,8 +579,12 @@ xfs_file_compat_ioctl( case FS_IOC_GETFSMAP: case XFS_IOC_SCRUB_METADATA: return xfs_file_ioctl(filp, cmd, p); -#ifndef BROKEN_X86_ALIGNMENT - /* These are handled fine if no alignment issues */ +#if !defined(BROKEN_X86_ALIGNMENT) || defined(CONFIG_X86_X32) + /* + * These are handled fine if no alignment issues. To support x32 + * which uses native 64-bit alignment we must emit these cases in + * addition to the ia-32 compat set below. + */ case XFS_IOC_ALLOCSP: case XFS_IOC_FREESP: case XFS_IOC_RESVSP: @@ -593,8 +597,16 @@ xfs_file_compat_ioctl( case XFS_IOC_FSGROWFSDATA: case XFS_IOC_FSGROWFSRT: case XFS_IOC_ZERO_RANGE: +#ifdef CONFIG_X86_X32 + /* + * x32 special: this gets a different cmd number from the ia-32 compat + * case below; the associated data will match native 64-bit alignment. + */ + case XFS_IOC_SWAPEXT: +#endif return xfs_file_ioctl(filp, cmd, p); -#else +#endif +#if defined(BROKEN_X86_ALIGNMENT) case XFS_IOC_ALLOCSP_32: case XFS_IOC_FREESP_32: case XFS_IOC_ALLOCSP64_32: |