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>
diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c
index b044f7d..5001dca 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: