1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2017 Oracle. All Rights Reserved.
4 * Author: Darrick J. Wong <darrick.wong@oracle.com>
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 "scrub/scrub.h"
16 #include "scrub/common.h"
17
18 /* Set us up to scrub a symbolic link. */
19 int
xchk_setup_symlink(struct xfs_scrub * sc,struct xfs_inode * ip)20 xchk_setup_symlink(
21 struct xfs_scrub *sc,
22 struct xfs_inode *ip)
23 {
24 /* Allocate the buffer without the inode lock held. */
25 sc->buf = kvzalloc(XFS_SYMLINK_MAXLEN + 1, GFP_KERNEL);
26 if (!sc->buf)
27 return -ENOMEM;
28
29 return xchk_setup_inode_contents(sc, ip, 0);
30 }
31
32 /* Symbolic links. */
33
34 int
xchk_symlink(struct xfs_scrub * sc)35 xchk_symlink(
36 struct xfs_scrub *sc)
37 {
38 struct xfs_inode *ip = sc->ip;
39 struct xfs_ifork *ifp;
40 loff_t len;
41 int error = 0;
42
43 if (!S_ISLNK(VFS_I(ip)->i_mode))
44 return -ENOENT;
45 ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
46 len = ip->i_d.di_size;
47
48 /* Plausible size? */
49 if (len > XFS_SYMLINK_MAXLEN || len <= 0) {
50 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
51 goto out;
52 }
53
54 /* Inline symlink? */
55 if (ifp->if_flags & XFS_IFINLINE) {
56 if (len > XFS_IFORK_DSIZE(ip) ||
57 len > strnlen(ifp->if_u1.if_data, XFS_IFORK_DSIZE(ip)))
58 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
59 goto out;
60 }
61
62 /* Remote symlink; must read the contents. */
63 error = xfs_readlink_bmap_ilocked(sc->ip, sc->buf);
64 if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error))
65 goto out;
66 if (strnlen(sc->buf, XFS_SYMLINK_MAXLEN) < len)
67 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
68 out:
69 return error;
70 }
71