From 982d2616a2906113e433fdc0cfcc122f8d1bb60a Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 16 Dec 2025 18:30:08 +0100 Subject: [PATCH] xfs: validate that zoned RT devices are zone aligned Garbage collection assumes all zones contain the full amount of blocks. Mkfs already ensures this happens, but make the kernel check it as well to avoid getting into trouble due to fuzzers or mkfs bugs. Fixes: 2167eaabe2fa ("xfs: define the zoned on-disk format") Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Cc: stable@vger.kernel.org # v6.15 Signed-off-by: Carlos Maiolino --- fs/xfs/libxfs/xfs_sb.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c index cdd16dd805d77..94c272a2ae262 100644 --- a/fs/xfs/libxfs/xfs_sb.c +++ b/fs/xfs/libxfs/xfs_sb.c @@ -301,6 +301,21 @@ xfs_validate_rt_geometry( sbp->sb_rbmblocks != xfs_expected_rbmblocks(sbp)) return false; + if (xfs_sb_is_v5(sbp) && + (sbp->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_ZONED)) { + uint32_t mod; + + /* + * Zoned RT devices must be aligned to the RT group size, + * because garbage collection assumes that all zones have the + * same size to avoid insane complexity if that weren't the + * case. + */ + div_u64_rem(sbp->sb_rextents, sbp->sb_rgextents, &mod); + if (mod) + return false; + } + return true; } -- 2.47.3