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_trans.h"
14#include "xfs_inode.h"
15#include "xfs_symlink.h"
16#include "xfs_health.h"
17#include "xfs_symlink_remote.h"
18#include "scrub/scrub.h"
19#include "scrub/common.h"
20#include "scrub/health.h"
21#include "scrub/repair.h"
22
23/* Set us up to scrub a symbolic link. */
24int
25xchk_setup_symlink(
26	struct xfs_scrub	*sc)
27{
28	unsigned int		resblks = 0;
29	int			error;
30
31	/* Allocate the buffer without the inode lock held. */
32	sc->buf = kvzalloc(XFS_SYMLINK_MAXLEN + 1, XCHK_GFP_FLAGS);
33	if (!sc->buf)
34		return -ENOMEM;
35
36	if (xchk_could_repair(sc)) {
37		error = xrep_setup_symlink(sc, &resblks);
38		if (error)
39			return error;
40	}
41
42	return xchk_setup_inode_contents(sc, resblks);
43}
44
45/* Symbolic links. */
46
47int
48xchk_symlink(
49	struct xfs_scrub	*sc)
50{
51	struct xfs_inode	*ip = sc->ip;
52	struct xfs_ifork	*ifp;
53	loff_t			len;
54	int			error = 0;
55
56	if (!S_ISLNK(VFS_I(ip)->i_mode))
57		return -ENOENT;
58
59	if (xchk_file_looks_zapped(sc, XFS_SICK_INO_SYMLINK_ZAPPED)) {
60		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
61		return 0;
62	}
63
64	ifp = xfs_ifork_ptr(ip, XFS_DATA_FORK);
65	len = ip->i_disk_size;
66
67	/* Plausible size? */
68	if (len > XFS_SYMLINK_MAXLEN || len <= 0) {
69		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
70		return 0;
71	}
72
73	/* Inline symlink? */
74	if (ifp->if_format == XFS_DINODE_FMT_LOCAL) {
75		if (len > xfs_inode_data_fork_size(ip) ||
76		    len > strnlen(ifp->if_data, xfs_inode_data_fork_size(ip)))
77			xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
78		return 0;
79	}
80
81	/* Remote symlink; must read the contents. */
82	error = xfs_symlink_remote_read(sc->ip, sc->buf);
83	if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error))
84		return error;
85	if (strnlen(sc->buf, XFS_SYMLINK_MAXLEN) < len)
86		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
87
88	/* If a remote symlink is clean, it is clearly not zapped. */
89	xchk_mark_healthy_if_clean(sc, XFS_SICK_INO_SYMLINK_ZAPPED);
90	return 0;
91}
92