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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>
hifive-unleashed-5.1
Nick Bowler 2018-12-17 09:35:27 -08:00 committed by Darrick J. Wong
parent 7ca860e3c1
commit a9d25bde1e
1 changed files with 15 additions and 3 deletions
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18
fs/xfs/xfs_ioctl32.c
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@ -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: