From ba150ce63453ccd74bae1404c1dfedbd01ecfd55 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Mon, 13 Jul 2026 23:06:59 -0700 Subject: [PATCH] xfs: fully check the parent handle when it points to the rootdir LOLLM noticed that the directory tree path checking declares the path to be ok if the inumber in the parent pointer reaches the root directory. Unfortunately, it neglects to check that the generation is correct. Fix that by moving the generation check up. Cc: stable@vger.kernel.org # v6.10 Fixes: 928b721a11789a ("xfs: teach online scrub to find directory tree structure problems") Signed-off-by: "Darrick J. Wong" Assisted-by: LOLLM # finding obvious bugs Reviewed-by: Christoph Hellwig Signed-off-by: Carlos Maiolino --- fs/xfs/scrub/dirtree.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/fs/xfs/scrub/dirtree.c b/fs/xfs/scrub/dirtree.c index c6a210f7508f..b2cf6e5439d9 100644 --- a/fs/xfs/scrub/dirtree.c +++ b/fs/xfs/scrub/dirtree.c @@ -383,6 +383,14 @@ xchk_dirpath_step_up( goto out_scanlock; } + /* The handle encoded in the parent pointer must match. */ + if (VFS_I(dp)->i_generation != be32_to_cpu(dl->pptr_rec.p_gen)) { + trace_xchk_dirpath_badgen(dl->sc, dp, path->path_nr, + path->nr_steps, &dl->xname, &dl->pptr_rec); + error = -EFSCORRUPTED; + goto out_scanlock; + } + /* We've reached the root directory; the path is ok. */ if (parent_ino == dl->root_ino) { xchk_dirpath_set_outcome(dl, path, XCHK_DIRPATH_OK); @@ -411,14 +419,6 @@ xchk_dirpath_step_up( goto out_scanlock; } - /* The handle encoded in the parent pointer must match. */ - if (VFS_I(dp)->i_generation != be32_to_cpu(dl->pptr_rec.p_gen)) { - trace_xchk_dirpath_badgen(dl->sc, dp, path->path_nr, - path->nr_steps, &dl->xname, &dl->pptr_rec); - error = -EFSCORRUPTED; - goto out_scanlock; - } - /* Parent pointer must point up to a directory. */ if (!S_ISDIR(VFS_I(dp)->i_mode)) { trace_xchk_dirpath_nondir_parent(dl->sc, dp, path->path_nr, -- 2.47.3