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

source code of linux/fs/xfs/scrub/symlink.c