1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
4  * Copyright (C) 2017 Oracle.
5  * All Rights Reserved.
6  */
7 #include "xfs.h"
8 #include "xfs_fs.h"
9 #include "xfs_format.h"
10 #include "xfs_shared.h"
11 #include "xfs_trans_resv.h"
12 #include "xfs_bit.h"
13 #include "xfs_mount.h"
14 #include "xfs_ag.h"
15 
16 /* Find the size of the AG, in blocks. */
17 inline xfs_agblock_t
xfs_ag_block_count(struct xfs_mount * mp,xfs_agnumber_t agno)18 xfs_ag_block_count(
19 	struct xfs_mount	*mp,
20 	xfs_agnumber_t		agno)
21 {
22 	ASSERT(agno < mp->m_sb.sb_agcount);
23 
24 	if (agno < mp->m_sb.sb_agcount - 1)
25 		return mp->m_sb.sb_agblocks;
26 	return mp->m_sb.sb_dblocks - (agno * mp->m_sb.sb_agblocks);
27 }
28 
29 /*
30  * Verify that an AG block number pointer neither points outside the AG
31  * nor points at static metadata.
32  */
33 inline bool
xfs_verify_agbno(struct xfs_mount * mp,xfs_agnumber_t agno,xfs_agblock_t agbno)34 xfs_verify_agbno(
35 	struct xfs_mount	*mp,
36 	xfs_agnumber_t		agno,
37 	xfs_agblock_t		agbno)
38 {
39 	xfs_agblock_t		eoag;
40 
41 	eoag = xfs_ag_block_count(mp, agno);
42 	if (agbno >= eoag)
43 		return false;
44 	if (agbno <= XFS_AGFL_BLOCK(mp))
45 		return false;
46 	return true;
47 }
48 
49 /*
50  * Verify that an FS block number pointer neither points outside the
51  * filesystem nor points at static AG metadata.
52  */
53 inline bool
xfs_verify_fsbno(struct xfs_mount * mp,xfs_fsblock_t fsbno)54 xfs_verify_fsbno(
55 	struct xfs_mount	*mp,
56 	xfs_fsblock_t		fsbno)
57 {
58 	xfs_agnumber_t		agno = XFS_FSB_TO_AGNO(mp, fsbno);
59 
60 	if (agno >= mp->m_sb.sb_agcount)
61 		return false;
62 	return xfs_verify_agbno(mp, agno, XFS_FSB_TO_AGBNO(mp, fsbno));
63 }
64 
65 /*
66  * Verify that a data device extent is fully contained inside the filesystem,
67  * does not cross an AG boundary, and does not point at static metadata.
68  */
69 bool
xfs_verify_fsbext(struct xfs_mount * mp,xfs_fsblock_t fsbno,xfs_fsblock_t len)70 xfs_verify_fsbext(
71 	struct xfs_mount	*mp,
72 	xfs_fsblock_t		fsbno,
73 	xfs_fsblock_t		len)
74 {
75 	if (fsbno + len <= fsbno)
76 		return false;
77 
78 	if (!xfs_verify_fsbno(mp, fsbno))
79 		return false;
80 
81 	if (!xfs_verify_fsbno(mp, fsbno + len - 1))
82 		return false;
83 
84 	return  XFS_FSB_TO_AGNO(mp, fsbno) ==
85 		XFS_FSB_TO_AGNO(mp, fsbno + len - 1);
86 }
87 
88 /* Calculate the first and last possible inode number in an AG. */
89 inline void
xfs_agino_range(struct xfs_mount * mp,xfs_agnumber_t agno,xfs_agino_t * first,xfs_agino_t * last)90 xfs_agino_range(
91 	struct xfs_mount	*mp,
92 	xfs_agnumber_t		agno,
93 	xfs_agino_t		*first,
94 	xfs_agino_t		*last)
95 {
96 	xfs_agblock_t		bno;
97 	xfs_agblock_t		eoag;
98 
99 	eoag = xfs_ag_block_count(mp, agno);
100 
101 	/*
102 	 * Calculate the first inode, which will be in the first
103 	 * cluster-aligned block after the AGFL.
104 	 */
105 	bno = round_up(XFS_AGFL_BLOCK(mp) + 1, M_IGEO(mp)->cluster_align);
106 	*first = XFS_AGB_TO_AGINO(mp, bno);
107 
108 	/*
109 	 * Calculate the last inode, which will be at the end of the
110 	 * last (aligned) cluster that can be allocated in the AG.
111 	 */
112 	bno = round_down(eoag, M_IGEO(mp)->cluster_align);
113 	*last = XFS_AGB_TO_AGINO(mp, bno) - 1;
114 }
115 
116 /*
117  * Verify that an AG inode number pointer neither points outside the AG
118  * nor points at static metadata.
119  */
120 inline bool
xfs_verify_agino(struct xfs_mount * mp,xfs_agnumber_t agno,xfs_agino_t agino)121 xfs_verify_agino(
122 	struct xfs_mount	*mp,
123 	xfs_agnumber_t		agno,
124 	xfs_agino_t		agino)
125 {
126 	xfs_agino_t		first;
127 	xfs_agino_t		last;
128 
129 	xfs_agino_range(mp, agno, &first, &last);
130 	return agino >= first && agino <= last;
131 }
132 
133 /*
134  * Verify that an AG inode number pointer neither points outside the AG
135  * nor points at static metadata, or is NULLAGINO.
136  */
137 bool
xfs_verify_agino_or_null(struct xfs_mount * mp,xfs_agnumber_t agno,xfs_agino_t agino)138 xfs_verify_agino_or_null(
139 	struct xfs_mount	*mp,
140 	xfs_agnumber_t		agno,
141 	xfs_agino_t		agino)
142 {
143 	return agino == NULLAGINO || xfs_verify_agino(mp, agno, agino);
144 }
145 
146 /*
147  * Verify that an FS inode number pointer neither points outside the
148  * filesystem nor points at static AG metadata.
149  */
150 inline bool
xfs_verify_ino(struct xfs_mount * mp,xfs_ino_t ino)151 xfs_verify_ino(
152 	struct xfs_mount	*mp,
153 	xfs_ino_t		ino)
154 {
155 	xfs_agnumber_t		agno = XFS_INO_TO_AGNO(mp, ino);
156 	xfs_agino_t		agino = XFS_INO_TO_AGINO(mp, ino);
157 
158 	if (agno >= mp->m_sb.sb_agcount)
159 		return false;
160 	if (XFS_AGINO_TO_INO(mp, agno, agino) != ino)
161 		return false;
162 	return xfs_verify_agino(mp, agno, agino);
163 }
164 
165 /* Is this an internal inode number? */
166 inline bool
xfs_internal_inum(struct xfs_mount * mp,xfs_ino_t ino)167 xfs_internal_inum(
168 	struct xfs_mount	*mp,
169 	xfs_ino_t		ino)
170 {
171 	return ino == mp->m_sb.sb_rbmino || ino == mp->m_sb.sb_rsumino ||
172 		(xfs_has_quota(mp) &&
173 		 xfs_is_quota_inode(&mp->m_sb, ino));
174 }
175 
176 /*
177  * Verify that a directory entry's inode number doesn't point at an internal
178  * inode, empty space, or static AG metadata.
179  */
180 bool
xfs_verify_dir_ino(struct xfs_mount * mp,xfs_ino_t ino)181 xfs_verify_dir_ino(
182 	struct xfs_mount	*mp,
183 	xfs_ino_t		ino)
184 {
185 	if (xfs_internal_inum(mp, ino))
186 		return false;
187 	return xfs_verify_ino(mp, ino);
188 }
189 
190 /*
191  * Verify that an realtime block number pointer doesn't point off the
192  * end of the realtime device.
193  */
194 inline bool
xfs_verify_rtbno(struct xfs_mount * mp,xfs_rtblock_t rtbno)195 xfs_verify_rtbno(
196 	struct xfs_mount	*mp,
197 	xfs_rtblock_t		rtbno)
198 {
199 	return rtbno < mp->m_sb.sb_rblocks;
200 }
201 
202 /* Verify that a realtime device extent is fully contained inside the volume. */
203 bool
xfs_verify_rtext(struct xfs_mount * mp,xfs_rtblock_t rtbno,xfs_rtblock_t len)204 xfs_verify_rtext(
205 	struct xfs_mount	*mp,
206 	xfs_rtblock_t		rtbno,
207 	xfs_rtblock_t		len)
208 {
209 	if (rtbno + len <= rtbno)
210 		return false;
211 
212 	if (!xfs_verify_rtbno(mp, rtbno))
213 		return false;
214 
215 	return xfs_verify_rtbno(mp, rtbno + len - 1);
216 }
217 
218 /* Calculate the range of valid icount values. */
219 inline void
xfs_icount_range(struct xfs_mount * mp,unsigned long long * min,unsigned long long * max)220 xfs_icount_range(
221 	struct xfs_mount	*mp,
222 	unsigned long long	*min,
223 	unsigned long long	*max)
224 {
225 	unsigned long long	nr_inos = 0;
226 	struct xfs_perag	*pag;
227 	xfs_agnumber_t		agno;
228 
229 	/* root, rtbitmap, rtsum all live in the first chunk */
230 	*min = XFS_INODES_PER_CHUNK;
231 
232 	for_each_perag(mp, agno, pag) {
233 		xfs_agino_t	first, last;
234 
235 		xfs_agino_range(mp, agno, &first, &last);
236 		nr_inos += last - first + 1;
237 	}
238 	*max = nr_inos;
239 }
240 
241 /* Sanity-checking of inode counts. */
242 bool
xfs_verify_icount(struct xfs_mount * mp,unsigned long long icount)243 xfs_verify_icount(
244 	struct xfs_mount	*mp,
245 	unsigned long long	icount)
246 {
247 	unsigned long long	min, max;
248 
249 	xfs_icount_range(mp, &min, &max);
250 	return icount >= min && icount <= max;
251 }
252 
253 /* Sanity-checking of dir/attr block offsets. */
254 bool
xfs_verify_dablk(struct xfs_mount * mp,xfs_fileoff_t dabno)255 xfs_verify_dablk(
256 	struct xfs_mount	*mp,
257 	xfs_fileoff_t		dabno)
258 {
259 	xfs_dablk_t		max_dablk = -1U;
260 
261 	return dabno <= max_dablk;
262 }
263 
264 /* Check that a file block offset does not exceed the maximum. */
265 bool
xfs_verify_fileoff(struct xfs_mount * mp,xfs_fileoff_t off)266 xfs_verify_fileoff(
267 	struct xfs_mount	*mp,
268 	xfs_fileoff_t		off)
269 {
270 	return off <= XFS_MAX_FILEOFF;
271 }
272 
273 /* Check that a range of file block offsets do not exceed the maximum. */
274 bool
xfs_verify_fileext(struct xfs_mount * mp,xfs_fileoff_t off,xfs_fileoff_t len)275 xfs_verify_fileext(
276 	struct xfs_mount	*mp,
277 	xfs_fileoff_t		off,
278 	xfs_fileoff_t		len)
279 {
280 	if (off + len <= off)
281 		return false;
282 
283 	if (!xfs_verify_fileoff(mp, off))
284 		return false;
285 
286 	return xfs_verify_fileoff(mp, off + len - 1);
287 }
288