[PATCH 1/6] xfs: cross-reference the rtgroup superblock extent, not block

["Darrick J. Wong" <djwong@kernel.org>]

From: Darrick J. Wong <djwong@kernel.org>

LOLLM noticed that when libxfs creates a realtime superblock, it will
create an rtrmapbt record covering the entire rtextent in which the
superblock lives.  However, the cross-referencing checks only look for
the first block, which means that we can miss a corrupt rtrmap record.
That will get picked up by the rtrmap scrubber, but we should make the
rgsuper scrubber more robust anyway.

Cc: <stable@vger.kernel.org> # v6.13
Fixes: 3f1bdf50ab1b9c ("xfs: scrub the realtime group superblock")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
---
 fs/xfs/scrub/rgsuper.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)


diff --git a/fs/xfs/scrub/rgsuper.c b/fs/xfs/scrub/rgsuper.c
index 2bd2c0351b35f7..6e2abe5dc27cd5 100644
--- a/fs/xfs/scrub/rgsuper.c
+++ b/fs/xfs/scrub/rgsuper.c
@@ -36,8 +36,10 @@ xchk_rgsuperblock_xref(
 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 		return;
 
-	xchk_xref_is_used_rt_space(sc, xfs_rgbno_to_rtb(sc->sr.rtg, 0), 1);
-	xchk_xref_is_only_rt_owned_by(sc, 0, 1, &XFS_RMAP_OINFO_FS);
+	xchk_xref_is_used_rt_space(sc, xfs_rgbno_to_rtb(sc->sr.rtg, 0),
+			sc->mp->m_sb.sb_rextsize);
+	xchk_xref_is_only_rt_owned_by(sc, 0, sc->mp->m_sb.sb_rextsize,
+			&XFS_RMAP_OINFO_FS);
 }
 
 int