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 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 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