1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2017-2023 Oracle.  All Rights Reserved.
4 * Author: Darrick J. Wong <djwong@kernel.org>
5 */
6#include "xfs.h"
7#include "xfs_fs.h"
8#include "xfs_shared.h"
9#include "xfs_format.h"
10#include "xfs_trans_resv.h"
11#include "xfs_mount.h"
12#include "xfs_log_format.h"
13#include "xfs_inode.h"
14#include "xfs_symlink.h"
15#include "xfs_health.h"
16#include "xfs_symlink_remote.h"
17#include "scrub/scrub.h"
18#include "scrub/common.h"
19#include "scrub/health.h"
20
21/* Set us up to scrub a symbolic link. */
22int
23xchk_setup_symlink(
24	struct xfs_scrub	*sc)
25{
26	/* Allocate the buffer without the inode lock held. */
27	sc->buf = kvzalloc(XFS_SYMLINK_MAXLEN + 1, XCHK_GFP_FLAGS);
28	if (!sc->buf)
29		return -ENOMEM;
30
31	return xchk_setup_inode_contents(sc, 0);
32}
33
34/* Symbolic links. */
35
36int
37xchk_symlink(
38	struct xfs_scrub	*sc)
39{
40	struct xfs_inode	*ip = sc->ip;
41	struct xfs_ifork	*ifp;
42	loff_t			len;
43	int			error = 0;
44
45	if (!S_ISLNK(VFS_I(ip)->i_mode))
46		return -ENOENT;
47
48	if (xchk_file_looks_zapped(sc, XFS_SICK_INO_SYMLINK_ZAPPED)) {
49		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
50		return 0;
51	}
52
53	ifp = xfs_ifork_ptr(ip, XFS_DATA_FORK);
54	len = ip->i_disk_size;
55
56	/* Plausible size? */
57	if (len > XFS_SYMLINK_MAXLEN || len <= 0) {
58		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
59		return 0;
60	}
61
62	/* Inline symlink? */
63	if (ifp->if_format == XFS_DINODE_FMT_LOCAL) {
64		if (len > xfs_inode_data_fork_size(ip) ||
65		    len > strnlen(ifp->if_data, xfs_inode_data_fork_size(ip)))
66			xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
67		return 0;
68	}
69
70	/* Remote symlink; must read the contents. */
71	error = xfs_symlink_remote_read(sc->ip, sc->buf);
72	if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error))
73		return error;
74	if (strnlen(sc->buf, XFS_SYMLINK_MAXLEN) < len)
75		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
76
77	/* If a remote symlink is clean, it is clearly not zapped. */
78	xchk_mark_healthy_if_clean(sc, XFS_SICK_INO_SYMLINK_ZAPPED);
79	return 0;
80}
81