xfs: fix getfsmap reporting past the last rt extent

[ Upstream commit d898137d789cac9ebe5eed9957e4cf25122ca524 ]

The realtime section ends at the last rt extent.  If the user configures
the rt geometry with an extent size that is not an integer factor of the
number of rt blocks, it's possible for there to be rt blocks past the
end of the last rt extent.  These tail blocks cannot ever be allocated
and will cause corruption reports if the last extent coincides with the
end of an rt bitmap block, so do not report consider them for the
GETFSMAP output.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Leah Rumancik <leah.rumancik@gmail.com>
Acked-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/xfs/xfs_fsmap.c b/fs/xfs/xfs_fsmap.c
index 5039d330ef98b844be43ff7e82376851bb447660..7b72992c14d948fb26e1a399c8f7c94c937f15ef 100644 (file)
--- a/fs/xfs/xfs_fsmap.c
+++ b/fs/xfs/xfs_fsmap.c
@@ -529,7 +529,7 @@ __xfs_getfsmap_rtdev(
        uint64_t                        eofs;
        int                             error = 0;
 
-       eofs = XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
+       eofs = XFS_FSB_TO_BB(mp, mp->m_sb.sb_rextents * mp->m_sb.sb_rextsize);
        if (keys[0].fmr_physical >= eofs)
                return 0;
        start_rtb = XFS_BB_TO_FSBT(mp,