From: kbuild test robot <lkp@intel.com>
To: Matthew Garrett <matthewgarrett@google.com>
Cc: kbuild-all@01.org, linux-integrity@vger.kernel.org,
zohar@linux.vnet.ibm.com, dmitry.kasatkin@gmail.com,
miklos@szeredi.hu, linux-fsdevel@vger.kernel.org,
viro@zeniv.linux.org.uk,
Matthew Garrett <matthewgarrett@google.com>,
Matthew Garrett <mjg59@google.com>
Subject: Re: [PATCH V3 5/6] IMA: Add a ima-vfs-sig measurement template
Date: Sat, 18 May 2019 18:04:00 +0800 [thread overview]
Message-ID: <201905181851.ooheCtWW%lkp@intel.com> (raw)
In-Reply-To: <20190517212448.14256-6-matthewgarrett@google.com>
Hi Matthew,
I love your patch! Perhaps something to improve:
[auto build test WARNING on integrity/next-integrity]
[also build test WARNING on v5.1 next-20190517]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Matthew-Garrett/IMA-Support-asking-the-VFS-for-a-file-hash/20190518-150531
base: https://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity.git next-integrity
reproduce:
# apt-get install sparse
make ARCH=x86_64 allmodconfig
make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__'
If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>
sparse warnings: (new ones prefixed by >>)
security/integrity/ima/ima_template_lib.c:110:60: sparse: sparse: restricted __le32 degrades to integer
security/integrity/ima/ima_template_lib.c:193:49: sparse: sparse: cast to restricted __le32
>> security/integrity/ima/ima_template_lib.c:299:66: sparse: sparse: Using plain integer as NULL pointer
vim +299 security/integrity/ima/ima_template_lib.c
3ce1217d6 Roberto Sassu 2013-06-07 100
3ce1217d6 Roberto Sassu 2013-06-07 101 static void ima_show_template_data_binary(struct seq_file *m,
3ce1217d6 Roberto Sassu 2013-06-07 102 enum ima_show_type show,
3ce1217d6 Roberto Sassu 2013-06-07 103 enum data_formats datafmt,
3ce1217d6 Roberto Sassu 2013-06-07 104 struct ima_field_data *field_data)
3ce1217d6 Roberto Sassu 2013-06-07 105 {
c019e307a Roberto Sassu 2014-02-03 106 u32 len = (show == IMA_SHOW_BINARY_OLD_STRING_FMT) ?
c019e307a Roberto Sassu 2014-02-03 107 strlen(field_data->data) : field_data->len;
c019e307a Roberto Sassu 2014-02-03 108
d68a6fe9f Mimi Zohar 2016-12-19 109 if (show != IMA_SHOW_BINARY_NO_FIELD_LEN) {
d68a6fe9f Mimi Zohar 2016-12-19 @110 u32 field_len = !ima_canonical_fmt ? len : cpu_to_le32(len);
d68a6fe9f Mimi Zohar 2016-12-19 111
d68a6fe9f Mimi Zohar 2016-12-19 112 ima_putc(m, &field_len, sizeof(field_len));
d68a6fe9f Mimi Zohar 2016-12-19 113 }
3e8e5503a Roberto Sassu 2013-11-08 114
c019e307a Roberto Sassu 2014-02-03 115 if (!len)
3ce1217d6 Roberto Sassu 2013-06-07 116 return;
3e8e5503a Roberto Sassu 2013-11-08 117
c019e307a Roberto Sassu 2014-02-03 118 ima_putc(m, field_data->data, len);
3ce1217d6 Roberto Sassu 2013-06-07 119 }
3ce1217d6 Roberto Sassu 2013-06-07 120
3ce1217d6 Roberto Sassu 2013-06-07 121 static void ima_show_template_field_data(struct seq_file *m,
3ce1217d6 Roberto Sassu 2013-06-07 122 enum ima_show_type show,
3ce1217d6 Roberto Sassu 2013-06-07 123 enum data_formats datafmt,
3ce1217d6 Roberto Sassu 2013-06-07 124 struct ima_field_data *field_data)
3ce1217d6 Roberto Sassu 2013-06-07 125 {
3ce1217d6 Roberto Sassu 2013-06-07 126 switch (show) {
3ce1217d6 Roberto Sassu 2013-06-07 127 case IMA_SHOW_ASCII:
3ce1217d6 Roberto Sassu 2013-06-07 128 ima_show_template_data_ascii(m, show, datafmt, field_data);
3ce1217d6 Roberto Sassu 2013-06-07 129 break;
3ce1217d6 Roberto Sassu 2013-06-07 130 case IMA_SHOW_BINARY:
3e8e5503a Roberto Sassu 2013-11-08 131 case IMA_SHOW_BINARY_NO_FIELD_LEN:
c019e307a Roberto Sassu 2014-02-03 132 case IMA_SHOW_BINARY_OLD_STRING_FMT:
3ce1217d6 Roberto Sassu 2013-06-07 133 ima_show_template_data_binary(m, show, datafmt, field_data);
3ce1217d6 Roberto Sassu 2013-06-07 134 break;
3ce1217d6 Roberto Sassu 2013-06-07 135 default:
3ce1217d6 Roberto Sassu 2013-06-07 136 break;
3ce1217d6 Roberto Sassu 2013-06-07 137 }
3ce1217d6 Roberto Sassu 2013-06-07 138 }
3ce1217d6 Roberto Sassu 2013-06-07 139
3ce1217d6 Roberto Sassu 2013-06-07 140 void ima_show_template_digest(struct seq_file *m, enum ima_show_type show,
3ce1217d6 Roberto Sassu 2013-06-07 141 struct ima_field_data *field_data)
3ce1217d6 Roberto Sassu 2013-06-07 142 {
3ce1217d6 Roberto Sassu 2013-06-07 143 ima_show_template_field_data(m, show, DATA_FMT_DIGEST, field_data);
3ce1217d6 Roberto Sassu 2013-06-07 144 }
3ce1217d6 Roberto Sassu 2013-06-07 145
4d7aeee73 Roberto Sassu 2013-06-07 146 void ima_show_template_digest_ng(struct seq_file *m, enum ima_show_type show,
4d7aeee73 Roberto Sassu 2013-06-07 147 struct ima_field_data *field_data)
4d7aeee73 Roberto Sassu 2013-06-07 148 {
4d7aeee73 Roberto Sassu 2013-06-07 149 ima_show_template_field_data(m, show, DATA_FMT_DIGEST_WITH_ALGO,
4d7aeee73 Roberto Sassu 2013-06-07 150 field_data);
4d7aeee73 Roberto Sassu 2013-06-07 151 }
4d7aeee73 Roberto Sassu 2013-06-07 152
3ce1217d6 Roberto Sassu 2013-06-07 153 void ima_show_template_string(struct seq_file *m, enum ima_show_type show,
3ce1217d6 Roberto Sassu 2013-06-07 154 struct ima_field_data *field_data)
3ce1217d6 Roberto Sassu 2013-06-07 155 {
3ce1217d6 Roberto Sassu 2013-06-07 156 ima_show_template_field_data(m, show, DATA_FMT_STRING, field_data);
3ce1217d6 Roberto Sassu 2013-06-07 157 }
3ce1217d6 Roberto Sassu 2013-06-07 158
bcbc9b0cf Mimi Zohar 2013-07-23 159 void ima_show_template_sig(struct seq_file *m, enum ima_show_type show,
bcbc9b0cf Mimi Zohar 2013-07-23 160 struct ima_field_data *field_data)
bcbc9b0cf Mimi Zohar 2013-07-23 161 {
bcbc9b0cf Mimi Zohar 2013-07-23 162 ima_show_template_field_data(m, show, DATA_FMT_HEX, field_data);
bcbc9b0cf Mimi Zohar 2013-07-23 163 }
bcbc9b0cf Mimi Zohar 2013-07-23 164
b17fd9ecf Roberto Sassu 2017-05-16 165 /**
b17fd9ecf Roberto Sassu 2017-05-16 166 * ima_parse_buf() - Parses lengths and data from an input buffer
b17fd9ecf Roberto Sassu 2017-05-16 167 * @bufstartp: Buffer start address.
b17fd9ecf Roberto Sassu 2017-05-16 168 * @bufendp: Buffer end address.
b17fd9ecf Roberto Sassu 2017-05-16 169 * @bufcurp: Pointer to remaining (non-parsed) data.
b17fd9ecf Roberto Sassu 2017-05-16 170 * @maxfields: Length of fields array.
b17fd9ecf Roberto Sassu 2017-05-16 171 * @fields: Array containing lengths and pointers of parsed data.
b17fd9ecf Roberto Sassu 2017-05-16 172 * @curfields: Number of array items containing parsed data.
b17fd9ecf Roberto Sassu 2017-05-16 173 * @len_mask: Bitmap (if bit is set, data length should not be parsed).
b17fd9ecf Roberto Sassu 2017-05-16 174 * @enforce_mask: Check if curfields == maxfields and/or bufcurp == bufendp.
b17fd9ecf Roberto Sassu 2017-05-16 175 * @bufname: String identifier of the input buffer.
b17fd9ecf Roberto Sassu 2017-05-16 176 *
b17fd9ecf Roberto Sassu 2017-05-16 177 * Return: 0 on success, -EINVAL on error.
b17fd9ecf Roberto Sassu 2017-05-16 178 */
b17fd9ecf Roberto Sassu 2017-05-16 179 int ima_parse_buf(void *bufstartp, void *bufendp, void **bufcurp,
b17fd9ecf Roberto Sassu 2017-05-16 180 int maxfields, struct ima_field_data *fields, int *curfields,
b17fd9ecf Roberto Sassu 2017-05-16 181 unsigned long *len_mask, int enforce_mask, char *bufname)
b17fd9ecf Roberto Sassu 2017-05-16 182 {
b17fd9ecf Roberto Sassu 2017-05-16 183 void *bufp = bufstartp;
b17fd9ecf Roberto Sassu 2017-05-16 184 int i;
b17fd9ecf Roberto Sassu 2017-05-16 185
b17fd9ecf Roberto Sassu 2017-05-16 186 for (i = 0; i < maxfields; i++) {
b17fd9ecf Roberto Sassu 2017-05-16 187 if (len_mask == NULL || !test_bit(i, len_mask)) {
b17fd9ecf Roberto Sassu 2017-05-16 188 if (bufp > (bufendp - sizeof(u32)))
b17fd9ecf Roberto Sassu 2017-05-16 189 break;
b17fd9ecf Roberto Sassu 2017-05-16 190
b17fd9ecf Roberto Sassu 2017-05-16 191 fields[i].len = *(u32 *)bufp;
b17fd9ecf Roberto Sassu 2017-05-16 192 if (ima_canonical_fmt)
b17fd9ecf Roberto Sassu 2017-05-16 193 fields[i].len = le32_to_cpu(fields[i].len);
b17fd9ecf Roberto Sassu 2017-05-16 194
b17fd9ecf Roberto Sassu 2017-05-16 195 bufp += sizeof(u32);
b17fd9ecf Roberto Sassu 2017-05-16 196 }
b17fd9ecf Roberto Sassu 2017-05-16 197
b17fd9ecf Roberto Sassu 2017-05-16 198 if (bufp > (bufendp - fields[i].len))
b17fd9ecf Roberto Sassu 2017-05-16 199 break;
b17fd9ecf Roberto Sassu 2017-05-16 200
b17fd9ecf Roberto Sassu 2017-05-16 201 fields[i].data = bufp;
b17fd9ecf Roberto Sassu 2017-05-16 202 bufp += fields[i].len;
b17fd9ecf Roberto Sassu 2017-05-16 203 }
b17fd9ecf Roberto Sassu 2017-05-16 204
b17fd9ecf Roberto Sassu 2017-05-16 205 if ((enforce_mask & ENFORCE_FIELDS) && i != maxfields) {
b17fd9ecf Roberto Sassu 2017-05-16 206 pr_err("%s: nr of fields mismatch: expected: %d, current: %d\n",
b17fd9ecf Roberto Sassu 2017-05-16 207 bufname, maxfields, i);
b17fd9ecf Roberto Sassu 2017-05-16 208 return -EINVAL;
b17fd9ecf Roberto Sassu 2017-05-16 209 }
b17fd9ecf Roberto Sassu 2017-05-16 210
b17fd9ecf Roberto Sassu 2017-05-16 211 if ((enforce_mask & ENFORCE_BUFEND) && bufp != bufendp) {
b17fd9ecf Roberto Sassu 2017-05-16 212 pr_err("%s: buf end mismatch: expected: %p, current: %p\n",
b17fd9ecf Roberto Sassu 2017-05-16 213 bufname, bufendp, bufp);
b17fd9ecf Roberto Sassu 2017-05-16 214 return -EINVAL;
b17fd9ecf Roberto Sassu 2017-05-16 215 }
b17fd9ecf Roberto Sassu 2017-05-16 216
b17fd9ecf Roberto Sassu 2017-05-16 217 if (curfields)
b17fd9ecf Roberto Sassu 2017-05-16 218 *curfields = i;
b17fd9ecf Roberto Sassu 2017-05-16 219
b17fd9ecf Roberto Sassu 2017-05-16 220 if (bufcurp)
b17fd9ecf Roberto Sassu 2017-05-16 221 *bufcurp = bufp;
b17fd9ecf Roberto Sassu 2017-05-16 222
b17fd9ecf Roberto Sassu 2017-05-16 223 return 0;
b17fd9ecf Roberto Sassu 2017-05-16 224 }
b17fd9ecf Roberto Sassu 2017-05-16 225
4d7aeee73 Roberto Sassu 2013-06-07 226 static int ima_eventdigest_init_common(u8 *digest, u32 digestsize, u8 hash_algo,
b0b4536f1 Matthew Garrett 2019-05-17 227 struct ima_event_data *event_data,
b0b4536f1 Matthew Garrett 2019-05-17 228 struct ima_field_data *field_data,
b0b4536f1 Matthew Garrett 2019-05-17 229 bool from_vfs)
4d7aeee73 Roberto Sassu 2013-06-07 230 {
3ce1217d6 Roberto Sassu 2013-06-07 231 /*
4d7aeee73 Roberto Sassu 2013-06-07 232 * digest formats:
4d7aeee73 Roberto Sassu 2013-06-07 233 * - DATA_FMT_DIGEST: digest
4d7aeee73 Roberto Sassu 2013-06-07 234 * - DATA_FMT_DIGEST_WITH_ALGO: [<hash algo>] + ':' + '\0' + digest,
4d7aeee73 Roberto Sassu 2013-06-07 235 * where <hash algo> is provided if the hash algoritm is not
4d7aeee73 Roberto Sassu 2013-06-07 236 * SHA1 or MD5
4d7aeee73 Roberto Sassu 2013-06-07 237 */
4d7aeee73 Roberto Sassu 2013-06-07 238 u8 buffer[CRYPTO_MAX_ALG_NAME + 2 + IMA_MAX_DIGEST_SIZE] = { 0 };
4d7aeee73 Roberto Sassu 2013-06-07 239 enum data_formats fmt = DATA_FMT_DIGEST;
4d7aeee73 Roberto Sassu 2013-06-07 240 u32 offset = 0;
4d7aeee73 Roberto Sassu 2013-06-07 241
b0b4536f1 Matthew Garrett 2019-05-17 242 if (from_vfs)
b0b4536f1 Matthew Garrett 2019-05-17 243 offset += snprintf(buffer, 5, "vfs:");
b0b4536f1 Matthew Garrett 2019-05-17 244
dcf4e3928 Roberto Sassu 2013-11-08 245 if (hash_algo < HASH_ALGO__LAST) {
4d7aeee73 Roberto Sassu 2013-06-07 246 fmt = DATA_FMT_DIGEST_WITH_ALGO;
b0b4536f1 Matthew Garrett 2019-05-17 247 offset += snprintf(buffer + offset, CRYPTO_MAX_ALG_NAME + 1,
b0b4536f1 Matthew Garrett 2019-05-17 248 "%s", hash_algo_name[hash_algo]);
4d7aeee73 Roberto Sassu 2013-06-07 249 buffer[offset] = ':';
4d7aeee73 Roberto Sassu 2013-06-07 250 offset += 2;
4d7aeee73 Roberto Sassu 2013-06-07 251 }
4d7aeee73 Roberto Sassu 2013-06-07 252
4d7aeee73 Roberto Sassu 2013-06-07 253 if (digest)
4d7aeee73 Roberto Sassu 2013-06-07 254 memcpy(buffer + offset, digest, digestsize);
4d7aeee73 Roberto Sassu 2013-06-07 255 else
4d7aeee73 Roberto Sassu 2013-06-07 256 /*
4d7aeee73 Roberto Sassu 2013-06-07 257 * If digest is NULL, the event being recorded is a violation.
4d7aeee73 Roberto Sassu 2013-06-07 258 * Make room for the digest by increasing the offset of
4d7aeee73 Roberto Sassu 2013-06-07 259 * IMA_DIGEST_SIZE.
4d7aeee73 Roberto Sassu 2013-06-07 260 */
4d7aeee73 Roberto Sassu 2013-06-07 261 offset += IMA_DIGEST_SIZE;
4d7aeee73 Roberto Sassu 2013-06-07 262
4d7aeee73 Roberto Sassu 2013-06-07 263 return ima_write_template_field_data(buffer, offset + digestsize,
4d7aeee73 Roberto Sassu 2013-06-07 264 fmt, field_data);
4d7aeee73 Roberto Sassu 2013-06-07 265 }
4d7aeee73 Roberto Sassu 2013-06-07 266
4d7aeee73 Roberto Sassu 2013-06-07 267 /*
4d7aeee73 Roberto Sassu 2013-06-07 268 * This function writes the digest of an event (with size limit).
3ce1217d6 Roberto Sassu 2013-06-07 269 */
23b574193 Roberto Sassu 2015-04-11 270 int ima_eventdigest_init(struct ima_event_data *event_data,
3ce1217d6 Roberto Sassu 2013-06-07 271 struct ima_field_data *field_data)
3ce1217d6 Roberto Sassu 2013-06-07 272 {
3ce1217d6 Roberto Sassu 2013-06-07 273 struct {
3ce1217d6 Roberto Sassu 2013-06-07 274 struct ima_digest_data hdr;
3ce1217d6 Roberto Sassu 2013-06-07 275 char digest[IMA_MAX_DIGEST_SIZE];
3ce1217d6 Roberto Sassu 2013-06-07 276 } hash;
4d7aeee73 Roberto Sassu 2013-06-07 277 u8 *cur_digest = NULL;
4d7aeee73 Roberto Sassu 2013-06-07 278 u32 cur_digestsize = 0;
3ce1217d6 Roberto Sassu 2013-06-07 279 struct inode *inode;
3ce1217d6 Roberto Sassu 2013-06-07 280 int result;
3ce1217d6 Roberto Sassu 2013-06-07 281
3ce1217d6 Roberto Sassu 2013-06-07 282 memset(&hash, 0, sizeof(hash));
3ce1217d6 Roberto Sassu 2013-06-07 283
8d94eb9b5 Roberto Sassu 2015-04-11 284 if (event_data->violation) /* recording a violation. */
3ce1217d6 Roberto Sassu 2013-06-07 285 goto out;
3ce1217d6 Roberto Sassu 2013-06-07 286
23b574193 Roberto Sassu 2015-04-11 287 if (ima_template_hash_algo_allowed(event_data->iint->ima_hash->algo)) {
23b574193 Roberto Sassu 2015-04-11 288 cur_digest = event_data->iint->ima_hash->digest;
23b574193 Roberto Sassu 2015-04-11 289 cur_digestsize = event_data->iint->ima_hash->length;
3ce1217d6 Roberto Sassu 2013-06-07 290 goto out;
3ce1217d6 Roberto Sassu 2013-06-07 291 }
3ce1217d6 Roberto Sassu 2013-06-07 292
23b574193 Roberto Sassu 2015-04-11 293 if (!event_data->file) /* missing info to re-calculate the digest */
3ce1217d6 Roberto Sassu 2013-06-07 294 return -EINVAL;
3ce1217d6 Roberto Sassu 2013-06-07 295
23b574193 Roberto Sassu 2015-04-11 296 inode = file_inode(event_data->file);
4d7aeee73 Roberto Sassu 2013-06-07 297 hash.hdr.algo = ima_template_hash_algo_allowed(ima_hash_algo) ?
4d7aeee73 Roberto Sassu 2013-06-07 298 ima_hash_algo : HASH_ALGO_SHA1;
16bcdb6da Matthew Garrett 2019-05-17 @299 result = ima_calc_file_hash(event_data->file, &hash.hdr, false);
3ce1217d6 Roberto Sassu 2013-06-07 300 if (result) {
3ce1217d6 Roberto Sassu 2013-06-07 301 integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode,
23b574193 Roberto Sassu 2015-04-11 302 event_data->filename, "collect_data",
3ce1217d6 Roberto Sassu 2013-06-07 303 "failed", result, 0);
3ce1217d6 Roberto Sassu 2013-06-07 304 return result;
3ce1217d6 Roberto Sassu 2013-06-07 305 }
4d7aeee73 Roberto Sassu 2013-06-07 306 cur_digest = hash.hdr.digest;
4d7aeee73 Roberto Sassu 2013-06-07 307 cur_digestsize = hash.hdr.length;
3ce1217d6 Roberto Sassu 2013-06-07 308 out:
712a49bd7 Roberto Sassu 2013-11-08 309 return ima_eventdigest_init_common(cur_digest, cur_digestsize,
b0b4536f1 Matthew Garrett 2019-05-17 310 HASH_ALGO__LAST, event_data, field_data, false);
3ce1217d6 Roberto Sassu 2013-06-07 311 }
3ce1217d6 Roberto Sassu 2013-06-07 312
:::::: The code at line 299 was first introduced by commit
:::::: 16bcdb6da2aa16a1457c8023e4b2efd9cfba5107 IMA: Optionally make use of filesystem-provided hashes
:::::: TO: Matthew Garrett <mjg59@google.com>
:::::: CC: 0day robot <lkp@intel.com>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
next prev parent reply other threads:[~2019-05-18 10:04 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-17 21:24 [PATCH V3 0/6] IMA: Support asking the VFS for a file hash Matthew Garrett
2019-05-17 21:24 ` [PATCH V3 1/6] VFS: Add a call to obtain a file's hash Matthew Garrett
2019-05-18 11:25 ` kbuild test robot
2019-05-20 7:10 ` Johannes Thumshirn
2019-05-17 21:24 ` [PATCH V3 2/6] FUSE: Allow filesystems to provide gethash methods Matthew Garrett
2019-05-17 21:24 ` [PATCH V3 3/6] IMA: Allow rule matching on filesystem subtype Matthew Garrett
2019-05-17 21:24 ` [PATCH V3 4/6] IMA: Optionally make use of filesystem-provided hashes Matthew Garrett
2019-05-17 21:24 ` [PATCH V3 5/6] IMA: Add a ima-vfs-sig measurement template Matthew Garrett
2019-05-18 10:04 ` kbuild test robot [this message]
2019-05-17 21:24 ` [PATCH V3 6/6] IMA: Allow profiles to define the desired IMA template Matthew Garrett
2019-05-17 23:47 ` Mimi Zohar
2019-05-20 20:59 ` Matthew Garrett
2019-05-20 21:26 ` Mimi Zohar
2019-05-21 0:10 ` prakhar srivastava
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