[021/115] xfs: validate explicit directory block buffer owners

Commit Message

Darrick J. Wong July 30, 2024, 12:29 a.m. UTC

From: Darrick J. Wong <[e-mail]>

Source kernel commit: 29b41ce919b7f0b0c2220e088e450d9b132bec36

Port the existing directory block header checking function to accept an
owner number instead of an xfs_inode, then update the callsites to use
xfs_da_args.owner when possible.

Signed-off-by: Darrick J. Wong <[e-mail]>
Reviewed-by: Christoph Hellwig <[e-mail]>
---
 db/namei.c              |    2 +-
 libxfs/xfs_dir2.h       |    1 +
 libxfs/xfs_dir2_block.c |   20 ++++++++++++--------
 libxfs/xfs_dir2_priv.h  |    4 ++--
 libxfs/xfs_exchmaps.c   |    2 +-
 5 files changed, 17 insertions(+), 12 deletions(-)

Patch

diff --git a/db/namei.c b/db/namei.c
index d2541b78a..303ca3448 100644
--- a/db/namei.c
+++ b/db/namei.c
@@ -337,7 +337,7 @@  list_blockdir(
 	unsigned int		end;
 	int			error;
 
-	error = xfs_dir3_block_read(NULL, dp, &bp);
+	error = xfs_dir3_block_read(NULL, dp, args->owner, &bp);
 	if (error)
 		return error;
 
diff --git a/libxfs/xfs_dir2.h b/libxfs/xfs_dir2.h
index d623bfdcd..eb3a5c350 100644
--- a/libxfs/xfs_dir2.h
+++ b/libxfs/xfs_dir2.h
@@ -103,6 +103,7 @@  extern int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino);
 
 xfs_failaddr_t xfs_dir3_leaf_header_check(struct xfs_buf *bp, xfs_ino_t owner);
 xfs_failaddr_t xfs_dir3_data_header_check(struct xfs_buf *bp, xfs_ino_t owner);
+xfs_failaddr_t xfs_dir3_block_header_check(struct xfs_buf *bp, xfs_ino_t owner);
 
 extern const struct xfs_buf_ops xfs_dir3_block_buf_ops;
 extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops;
diff --git a/libxfs/xfs_dir2_block.c b/libxfs/xfs_dir2_block.c
index 6107e01ca..82da0d327 100644
--- a/libxfs/xfs_dir2_block.c
+++ b/libxfs/xfs_dir2_block.c
@@ -112,17 +112,20 @@  const struct xfs_buf_ops xfs_dir3_block_buf_ops = {
 	.verify_struct = xfs_dir3_block_verify,
 };
 
-static xfs_failaddr_t
+xfs_failaddr_t
 xfs_dir3_block_header_check(
-	struct xfs_inode	*dp,
-	struct xfs_buf		*bp)
+	struct xfs_buf		*bp,
+	xfs_ino_t		owner)
 {
-	struct xfs_mount	*mp = dp->i_mount;
+	struct xfs_mount	*mp = bp->b_mount;
 
 	if (xfs_has_crc(mp)) {
 		struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
 
-		if (be64_to_cpu(hdr3->owner) != dp->i_ino)
+		if (hdr3->magic != cpu_to_be32(XFS_DIR3_BLOCK_MAGIC))
+			return __this_address;
+
+		if (be64_to_cpu(hdr3->owner) != owner)
 			return __this_address;
 	}
 
@@ -133,6 +136,7 @@  int
 xfs_dir3_block_read(
 	struct xfs_trans	*tp,
 	struct xfs_inode	*dp,
+	xfs_ino_t		owner,
 	struct xfs_buf		**bpp)
 {
 	struct xfs_mount	*mp = dp->i_mount;
@@ -145,7 +149,7 @@  xfs_dir3_block_read(
 		return err;
 
 	/* Check things that we can't do in the verifier. */
-	fa = xfs_dir3_block_header_check(dp, *bpp);
+	fa = xfs_dir3_block_header_check(*bpp, owner);
 	if (fa) {
 		__xfs_buf_mark_corrupt(*bpp, fa);
 		xfs_trans_brelse(tp, *bpp);
@@ -380,7 +384,7 @@  xfs_dir2_block_addname(
 	tp = args->trans;
 
 	/* Read the (one and only) directory block into bp. */
-	error = xfs_dir3_block_read(tp, dp, &bp);
+	error = xfs_dir3_block_read(tp, dp, args->owner, &bp);
 	if (error)
 		return error;
 
@@ -695,7 +699,7 @@  xfs_dir2_block_lookup_int(
 	dp = args->dp;
 	tp = args->trans;
 
-	error = xfs_dir3_block_read(tp, dp, &bp);
+	error = xfs_dir3_block_read(tp, dp, args->owner, &bp);
 	if (error)
 		return error;
 
diff --git a/libxfs/xfs_dir2_priv.h b/libxfs/xfs_dir2_priv.h
index 879aa2e9f..adbc544c9 100644
--- a/libxfs/xfs_dir2_priv.h
+++ b/libxfs/xfs_dir2_priv.h
@@ -50,8 +50,8 @@  extern int xfs_dir_cilookup_result(struct xfs_da_args *args,
 
 
 /* xfs_dir2_block.c */
-extern int xfs_dir3_block_read(struct xfs_trans *tp, struct xfs_inode *dp,
-			       struct xfs_buf **bpp);
+int xfs_dir3_block_read(struct xfs_trans *tp, struct xfs_inode *dp,
+		xfs_ino_t owner, struct xfs_buf **bpp);
 extern int xfs_dir2_block_addname(struct xfs_da_args *args);
 extern int xfs_dir2_block_lookup(struct xfs_da_args *args);
 extern int xfs_dir2_block_removename(struct xfs_da_args *args);
diff --git a/libxfs/xfs_exchmaps.c b/libxfs/xfs_exchmaps.c
index 21c501aab..71408d713 100644
--- a/libxfs/xfs_exchmaps.c
+++ b/libxfs/xfs_exchmaps.c
@@ -473,7 +473,7 @@  xfs_exchmaps_dir_to_sf(
 	if (!isblock)
 		return 0;
 
-	error = xfs_dir3_block_read(tp, xmi->xmi_ip2, &bp);
+	error = xfs_dir3_block_read(tp, xmi->xmi_ip2, xmi->xmi_ip2->i_ino, &bp);
 	if (error)
 		return error;