@@ -792,6 +792,37 @@ xfs_scrubv_check_barrier(
return 0;
}
+/*
+ * If the caller provided us with a nonzero inode number that isn't the ioctl
+ * file, try to grab a reference to it to eliminate all further untrusted inode
+ * lookups. If we can't get the inode, let each scrub function try again.
+ */
+STATIC struct xfs_inode *
+xchk_scrubv_open_by_handle(
+ struct xfs_mount *mp,
+ const struct xfs_scrub_vec_head *head)
+{
+ struct xfs_trans *tp;
+ struct xfs_inode *ip;
+ int error;
+
+ error = xfs_trans_alloc_empty(mp, &tp);
+ if (error)
+ return NULL;
+
+ error = xfs_iget(mp, tp, head->svh_ino, XCHK_IGET_FLAGS, 0, &ip);
+ xfs_trans_cancel(tp);
+ if (error)
+ return NULL;
+
+ if (VFS_I(ip)->i_generation != head->svh_gen) {
+ xfs_irele(ip);
+ return NULL;
+ }
+
+ return ip;
+}
+
/* Vectored scrub implementation to reduce ioctl calls. */
int
xfs_ioc_scrubv_metadata(
@@ -804,6 +835,7 @@ xfs_ioc_scrubv_metadata(
struct xfs_scrub_vec __user *uvectors;
struct xfs_inode *ip_in = XFS_I(file_inode(file));
struct xfs_mount *mp = ip_in->i_mount;
+ struct xfs_inode *handle_ip = NULL;
struct xfs_scrub_vec *v;
size_t vec_bytes;
unsigned int i;
@@ -848,6 +880,17 @@ xfs_ioc_scrubv_metadata(
trace_xchk_scrubv_item(mp, &head, i, v);
}
+ /*
+ * If the caller wants us to do a scrub-by-handle and the file used to
+ * call the ioctl is not the same file, load the incore inode and pin
+ * it across all the scrubv actions to avoid repeated UNTRUSTED
+ * lookups. The reference is not passed to deeper layers of scrub
+ * because each scrubber gets to decide its own strategy and return
+ * values for getting an inode.
+ */
+ if (head.svh_ino && head.svh_ino != ip_in->i_ino)
+ handle_ip = xchk_scrubv_open_by_handle(mp, &head);
+
/* Run all the scrubbers. */
for (i = 0, v = vectors; i < head.svh_nr; i++, v++) {
struct xfs_scrub_metadata sm = {
@@ -895,6 +938,8 @@ xfs_ioc_scrubv_metadata(
}
out_free:
+ if (handle_ip)
+ xfs_irele(handle_ip);
kfree(vectors);
return error;
}