xfs: provide a centralized method for verifying inline fork data

Source kernel commit: 9cfb9b47479e237d217dbcfafe034cbf98f45909

Replace the current haphazard dir2 shortform verifier callsites with a
centralized verifier function that can be called either with the default
verifier functions or with a custom set.  This helps us strengthen
integrity checking while providing us with flexibility for repair tools.

xfs_repair wants this to be able to supply its own verifier functions
when trying to fix possibly corrupt metadata.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

5 files changed, 94 insertions, 24 deletions

diff --git a/include/xfs_inode.h b/include/xfs_inode.h
index 11a549e367..92829a2556 100644
--- a/include/xfs_inode.h
+++ b/include/xfs_inode.h
@@ -162,6 +162,7 @@ extern void	libxfs_trans_ichgtime(struct xfs_trans *,
 extern int	libxfs_iflush_int (struct xfs_inode *, struct xfs_buf *);
 
 /* Inode Cache Interfaces */
+extern bool	libxfs_inode_verify_forks(struct xfs_inode *ip);
 extern int	libxfs_iget(struct xfs_mount *, struct xfs_trans *, xfs_ino_t,
 				uint, struct xfs_inode **);
 extern void	libxfs_iput(struct xfs_inode *);
diff --git a/libxfs/rdwr.c b/libxfs/rdwr.c
index 474e5ebc48..14afece464 100644
--- a/libxfs/rdwr.c
+++ b/libxfs/rdwr.c
@@ -1336,6 +1336,34 @@ struct cache_operations libxfs_bcache_operations = {
 extern kmem_zone_t	*xfs_ili_zone;
 extern kmem_zone_t	*xfs_inode_zone;
 
+/*
+ * If there are inline format data / attr forks attached to this inode,
+ * make sure they're not corrupt.
+ */
+bool
+libxfs_inode_verify_forks(
+	struct xfs_inode	*ip)
+{
+	xfs_failaddr_t		fa;
+
+	fa = xfs_ifork_verify_data(ip, &xfs_default_ifork_ops);
+	if (fa) {
+		xfs_alert(ip->i_mount,
+				"%s: bad inode %Lu inline data fork at %pF",
+				__func__, ip->i_ino, fa);
+		return false;
+	}
+
+	fa = xfs_ifork_verify_attr(ip, &xfs_default_ifork_ops);
+	if (fa) {
+		xfs_alert(ip->i_mount,
+				"%s: bad inode %Lu inline attr fork at %pF",
+				__func__, ip->i_ino, fa);
+		return false;
+	}
+	return true;
+}
+
 int
 libxfs_iget(xfs_mount_t *mp, xfs_trans_t *tp, xfs_ino_t ino, uint lock_flags,
 		xfs_inode_t **ipp)
@@ -1356,6 +1384,11 @@ libxfs_iget(xfs_mount_t *mp, xfs_trans_t *tp, xfs_ino_t ino, uint lock_flags,
 		return error;
 	}
 
+	if (!libxfs_inode_verify_forks(ip)) {
+		libxfs_iput(ip);
+		return -EFSCORRUPTED;
+	}
+
 	/*
 	 * set up the inode ops structure that the libxfs code relies on
 	 */
diff --git a/libxfs/util.c b/libxfs/util.c
index 584666c2b7..5e06424ff3 100644
--- a/libxfs/util.c
+++ b/libxfs/util.c
@@ -493,10 +493,8 @@ libxfs_iflush_int(xfs_inode_t *ip, xfs_buf_t *bp)
 	if (ip->i_d.di_version == 3)
 		VFS_I(ip)->i_version++;
 
-	/* Check the inline directory data. */
-	if (S_ISDIR(VFS_I(ip)->i_mode) &&
-	    ip->i_d.di_format == XFS_DINODE_FMT_LOCAL &&
-	    xfs_dir2_sf_verify(ip))
+	/* Check the inline fork data before we write out. */
+	if (!libxfs_inode_verify_forks(ip))
 		return -EFSCORRUPTED;
 
 	/*
diff --git a/libxfs/xfs_inode_fork.c b/libxfs/xfs_inode_fork.c
index ded3f83c0f..750d339e7f 100644
--- a/libxfs/xfs_inode_fork.c
+++ b/libxfs/xfs_inode_fork.c
@@ -31,6 +31,8 @@
 #include "xfs_da_format.h"
 #include "xfs_da_btree.h"
 #include "xfs_dir2_priv.h"
+#include "xfs_attr_leaf.h"
+#include "xfs_shared.h"
 
 
 kmem_zone_t *xfs_ifork_zone;
@@ -94,14 +96,6 @@ xfs_iformat_fork(
 	if (error)
 		return error;
 
-	/* Check inline dir contents. */
-	if (S_ISDIR(inode->i_mode) && dip->di_format == XFS_DINODE_FMT_LOCAL) {
-		if (xfs_dir2_sf_verify(ip)) {
-			xfs_idestroy_fork(ip, XFS_DATA_FORK);
-			return -EFSCORRUPTED;
-		}
-	}
-
 	if (xfs_is_reflink_inode(ip)) {
 		ASSERT(ip->i_cowfp == NULL);
 		xfs_ifork_init_cow(ip);
@@ -118,18 +112,6 @@ xfs_iformat_fork(
 		atp = (xfs_attr_shortform_t *)XFS_DFORK_APTR(dip);
 		size = be16_to_cpu(atp->hdr.totsize);
 
-		if (unlikely(size < sizeof(struct xfs_attr_sf_hdr))) {
-			xfs_warn(ip->i_mount,
-				"corrupt inode %Lu (bad attr fork size %Ld).",
-				(unsigned long long) ip->i_ino,
-				(long long) size);
-			XFS_CORRUPTION_ERROR("xfs_iformat(8)",
-					     XFS_ERRLEVEL_LOW,
-					     ip->i_mount, dip);
-			error = -EFSCORRUPTED;
-			break;
-		}
-
 		error = xfs_iformat_local(ip, dip, XFS_ATTR_FORK, size);
 		break;
 	case XFS_DINODE_FMT_EXTENTS:
@@ -737,3 +719,45 @@ xfs_ifork_init_cow(
 	ip->i_cformat = XFS_DINODE_FMT_EXTENTS;
 	ip->i_cnextents = 0;
 }
+
+/* Default fork content verifiers. */
+struct xfs_ifork_ops xfs_default_ifork_ops = {
+	.verify_attr	= xfs_attr_shortform_verify,
+	.verify_dir	= xfs_dir2_sf_verify,
+	.verify_symlink	= xfs_symlink_shortform_verify,
+};
+
+/* Verify the inline contents of the data fork of an inode. */
+xfs_failaddr_t
+xfs_ifork_verify_data(
+	struct xfs_inode	*ip,
+	struct xfs_ifork_ops	*ops)
+{
+	/* Non-local data fork, we're done. */
+	if (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL)
+		return NULL;
+
+	/* Check the inline data fork if there is one. */
+	switch (VFS_I(ip)->i_mode & S_IFMT) {
+	case S_IFDIR:
+		return ops->verify_dir(ip);
+	case S_IFLNK:
+		return ops->verify_symlink(ip);
+	default:
+		return NULL;
+	}
+}
+
+/* Verify the inline contents of the attr fork of an inode. */
+xfs_failaddr_t
+xfs_ifork_verify_attr(
+	struct xfs_inode	*ip,
+	struct xfs_ifork_ops	*ops)
+{
+	/* There has to be an attr fork allocated if aformat is local. */
+	if (ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)
+		return NULL;
+	if (!XFS_IFORK_PTR(ip, XFS_ATTR_FORK))
+		return __this_address;
+	return ops->verify_attr(ip);
+}
diff --git a/libxfs/xfs_inode_fork.h b/libxfs/xfs_inode_fork.h
index b9f0098e33..dd8aba0dd1 100644
--- a/libxfs/xfs_inode_fork.h
+++ b/libxfs/xfs_inode_fork.h
@@ -186,4 +186,18 @@ extern struct kmem_zone	*xfs_ifork_zone;
 
 extern void xfs_ifork_init_cow(struct xfs_inode *ip);
 
+typedef xfs_failaddr_t (*xfs_ifork_verifier_t)(struct xfs_inode *);
+
+struct xfs_ifork_ops {
+	xfs_ifork_verifier_t	verify_symlink;
+	xfs_ifork_verifier_t	verify_dir;
+	xfs_ifork_verifier_t	verify_attr;
+};
+extern struct xfs_ifork_ops	xfs_default_ifork_ops;
+
+xfs_failaddr_t xfs_ifork_verify_data(struct xfs_inode *ip,
+		struct xfs_ifork_ops *ops);
+xfs_failaddr_t xfs_ifork_verify_attr(struct xfs_inode *ip,
+		struct xfs_ifork_ops *ops);
+
 #endif	/* __XFS_INODE_FORK_H__ */