From: chas williams - CONTRACTOR <chas@cmf.nrl.navy.mil>
To: Chen Gang <gang.chen@asianux.com>
Cc: David.Woodhouse@intel.com, David Miller <davem@davemloft.net>,
krzysiek@podlesie.net, Joe Perches <joe@perches.com>,
edumazet@google.com, netdev <netdev@vger.kernel.org>
Subject: Re: [Suggestion] net/atm : for sprintf, need check the total write length whether larger than a page.
Date: Mon, 3 Dec 2012 10:48:25 -0500 [thread overview]
Message-ID: <20121203104825.78123ecc@thirdoffive.cmf.nrl.navy.mil> (raw)
In-Reply-To: <50BC6958.6080803@asianux.com>
yes this seems like it should be done. maybe this week i will try to
put something together unless you already have a patch somewhere.
On Mon, 03 Dec 2012 16:56:56 +0800
Chen Gang <gang.chen@asianux.com> wrote:
> Hello Maintainers:
>
> was this suggestion replied ? (it seems not).
>
> and please help to check whether this suggestion is valid.
>
> thanks.
>
> gchen.
>
>
> 于 2012年11月21日 12:29, Chen Gang 写道:
> > Hello David Miller:
> >
> > in net/atm/atm_sysfs.c:
> > suggest to check the write length whether larger than a page.
> > the length of parameter buf is one page size (reference: fill_read_buffer at fs/sysfs/file.c)
> > and the count of atm adresses are not limited (reference: atm_dev_ioctl -> atm_add_addr)
> >
> > thanks.
> >
> > gchen.
> >
> > 34 static ssize_t show_atmaddress(struct device *cdev,
> > 35 struct device_attribute *attr, char *buf)
> > 36 {
> > 37 unsigned long flags;
> > 38 char *pos = buf;
> > 39 struct atm_dev *adev = to_atm_dev(cdev);
> > 40 struct atm_dev_addr *aaddr;
> > 41 int bin[] = { 1, 2, 10, 6, 1 }, *fmt = bin;
> > 42 int i, j;
> > 43
> > 44 spin_lock_irqsave(&adev->lock, flags);
> > 45 list_for_each_entry(aaddr, &adev->local, entry) {
> > 46 for (i = 0, j = 0; i < ATM_ESA_LEN; ++i, ++j) {
> > 47 if (j == *fmt) {
> > 48 pos += sprintf(pos, ".");
> > 49 ++fmt;
> > 50 j = 0;
> > 51 }
> > 52 pos += sprintf(pos, "%02x",
> > 53 aaddr->addr.sas_addr.prv[i]);
> > 54 }
> > 55 pos += sprintf(pos, "\n");
> > 56 }
> > 57 spin_unlock_irqrestore(&adev->lock, flags);
> > 58
> > 59 return pos - buf;
> > 60 }
> > 61
> >
> >
> >
> > in net/atm/addr.c
> >
> > 67 int atm_add_addr(struct atm_dev *dev, const struct sockaddr_atmsvc *addr,
> > 68 enum atm_addr_type_t atype)
> > 69 {
> > 70 unsigned long flags;
> > 71 struct atm_dev_addr *this;
> > 72 struct list_head *head;
> > 73 int error;
> > 74
> > 75 error = check_addr(addr);
> > 76 if (error)
> > 77 return error;
> > 78 spin_lock_irqsave(&dev->lock, flags);
> > 79 if (atype == ATM_ADDR_LECS)
> > 80 head = &dev->lecs;
> > 81 else
> > 82 head = &dev->local;
> > 83 list_for_each_entry(this, head, entry) {
> > 84 if (identical(&this->addr, addr)) {
> > 85 spin_unlock_irqrestore(&dev->lock, flags);
> > 86 return -EEXIST;
> > 87 }
> > 88 }
> > 89 this = kmalloc(sizeof(struct atm_dev_addr), GFP_ATOMIC);
> > 90 if (!this) {
> > 91 spin_unlock_irqrestore(&dev->lock, flags);
> > 92 return -ENOMEM;
> > 93 }
> > 94 this->addr = *addr;
> > 95 list_add(&this->entry, head);
> > 96 spin_unlock_irqrestore(&dev->lock, flags);
> > 97 if (head == &dev->local)
> > 98 notify_sigd(dev);
> > 99 return 0;
> > 100 }
> > 101
> >
> >
> > in net/atm/resources.c
> >
> > 195 int atm_dev_ioctl(unsigned int cmd, void __user *arg, int compat)
> > 196 {
> > 197 void __user *buf;
> > 198 int error, len, number, size = 0;
> > 199 struct atm_dev *dev;
> > 200 struct list_head *p;
> > 201 int *tmp_buf, *tmp_p;
> > 202 int __user *sioc_len;
> > 203 int __user *iobuf_len;
> > 204
> > 205 #ifndef CONFIG_COMPAT
> > 206 compat = 0; /* Just so the compiler _knows_ */
> > 207 #endif
> > 208
> > 209 switch (cmd) {
> > 210 case ATM_GETNAMES:
> > 211 if (compat) {
> > 212 #ifdef CONFIG_COMPAT
> > 213 struct compat_atm_iobuf __user *ciobuf = arg;
> > 214 compat_uptr_t cbuf;
> > 215 iobuf_len = &ciobuf->length;
> > 216 if (get_user(cbuf, &ciobuf->buffer))
> > 217 return -EFAULT;
> > 218 buf = compat_ptr(cbuf);
> > 219 #endif
> > 220 } else {
> > 221 struct atm_iobuf __user *iobuf = arg;
> > 222 iobuf_len = &iobuf->length;
> > 223 if (get_user(buf, &iobuf->buffer))
> > 224 return -EFAULT;
> > 225 }
> > 226 if (get_user(len, iobuf_len))
> > 227 return -EFAULT;
> > 228 mutex_lock(&atm_dev_mutex);
> > 229 list_for_each(p, &atm_devs)
> > 230 size += sizeof(int);
> > 231 if (size > len) {
> > 232 mutex_unlock(&atm_dev_mutex);
> > 233 return -E2BIG;
> > 234 }
> > 235 tmp_buf = kmalloc(size, GFP_ATOMIC);
> > 236 if (!tmp_buf) {
> > 237 mutex_unlock(&atm_dev_mutex);
> > 238 return -ENOMEM;
> > 239 }
> > 240 tmp_p = tmp_buf;
> > 241 list_for_each(p, &atm_devs) {
> > 242 dev = list_entry(p, struct atm_dev, dev_list);
> > 243 *tmp_p++ = dev->number;
> > 244 }
> > 245 mutex_unlock(&atm_dev_mutex);
> > 246 error = ((copy_to_user(buf, tmp_buf, size)) ||
> > 247 put_user(size, iobuf_len))
> > 248 ? -EFAULT : 0;
> > 249 kfree(tmp_buf);
> > 250 return error;
> > 251 default:
> > 252 break;
> > 253 }
> > 254
> > 255 if (compat) {
> > 256 #ifdef CONFIG_COMPAT
> > 257 struct compat_atmif_sioc __user *csioc = arg;
> > 258 compat_uptr_t carg;
> > 259
> > 260 sioc_len = &csioc->length;
> > 261 if (get_user(carg, &csioc->arg))
> > 262 return -EFAULT;
> > 263 buf = compat_ptr(carg);
> > 264
> > 265 if (get_user(len, &csioc->length))
> > 266 return -EFAULT;
> > 267 if (get_user(number, &csioc->number))
> > 268 return -EFAULT;
> > 269 #endif
> > 270 } else {
> > 271 struct atmif_sioc __user *sioc = arg;
> > 272
> > 273 sioc_len = &sioc->length;
> > 274 if (get_user(buf, &sioc->arg))
> > 275 return -EFAULT;
> > 276 if (get_user(len, &sioc->length))
> > 277 return -EFAULT;
> > 278 if (get_user(number, &sioc->number))
> > 279 return -EFAULT;
> > 280 }
> > 281
> > 282 dev = try_then_request_module(atm_dev_lookup(number), "atm-device-%d",
> > 283 number);
> > 284 if (!dev)
> > 285 return -ENODEV;
> > 286
> > 287 switch (cmd) {
> > 288 case ATM_GETTYPE:
> > 289 size = strlen(dev->type) + 1;
> > 290 if (copy_to_user(buf, dev->type, size)) {
> > 291 error = -EFAULT;
> > 292 goto done;
> > 293 }
> > 294 break;
> > 295 case ATM_GETESI:
> > 296 size = ESI_LEN;
> > 297 if (copy_to_user(buf, dev->esi, size)) {
> > 298 error = -EFAULT;
> > 299 goto done;
> > 300 }
> > 301 break;
> > 302 case ATM_SETESI:
> > 303 {
> > 304 int i;
> > 305
> > 306 for (i = 0; i < ESI_LEN; i++)
> > 307 if (dev->esi[i]) {
> > 308 error = -EEXIST;
> > 309 goto done;
> > 310 }
> > 311 }
> > 312 /* fall through */
> > 313 case ATM_SETESIF:
> > 314 {
> > 315 unsigned char esi[ESI_LEN];
> > 316
> > 317 if (!capable(CAP_NET_ADMIN)) {
> > 318 error = -EPERM;
> > 319 goto done;
> > 320 }
> > 321 if (copy_from_user(esi, buf, ESI_LEN)) {
> > 322 error = -EFAULT;
> > 323 goto done;
> > 324 }
> > 325 memcpy(dev->esi, esi, ESI_LEN);
> > 326 error = ESI_LEN;
> > 327 goto done;
> > 328 }
> > 329 case ATM_GETSTATZ:
> > 330 if (!capable(CAP_NET_ADMIN)) {
> > 331 error = -EPERM;
> > 332 goto done;
> > 333 }
> > 334 /* fall through */
> > 335 case ATM_GETSTAT:
> > 336 size = sizeof(struct atm_dev_stats);
> > 337 error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
> > 338 if (error)
> > 339 goto done;
> > 340 break;
> > 341 case ATM_GETCIRANGE:
> > 342 size = sizeof(struct atm_cirange);
> > 343 if (copy_to_user(buf, &dev->ci_range, size)) {
> > 344 error = -EFAULT;
> > 345 goto done;
> > 346 }
> > 347 break;
> > 348 case ATM_GETLINKRATE:
> > 349 size = sizeof(int);
> > 350 if (copy_to_user(buf, &dev->link_rate, size)) {
> > 351 error = -EFAULT;
> > 352 goto done;
> > 353 }
> > 354 break;
> > 355 case ATM_RSTADDR:
> > 356 if (!capable(CAP_NET_ADMIN)) {
> > 357 error = -EPERM;
> > 358 goto done;
> > 359 }
> > 360 atm_reset_addr(dev, ATM_ADDR_LOCAL);
> > 361 break;
> > 362 case ATM_ADDADDR:
> > 363 case ATM_DELADDR:
> > 364 case ATM_ADDLECSADDR:
> > 365 case ATM_DELLECSADDR:
> > 366 {
> > 367 struct sockaddr_atmsvc addr;
> > 368
> > 369 if (!capable(CAP_NET_ADMIN)) {
> > 370 error = -EPERM;
> > 371 goto done;
> > 372 }
> > 373
> > 374 if (copy_from_user(&addr, buf, sizeof(addr))) {
> > 375 error = -EFAULT;
> > 376 goto done;
> > 377 }
> > 378 if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
> > 379 error = atm_add_addr(dev, &addr,
> > 380 (cmd == ATM_ADDADDR ?
> > 381 ATM_ADDR_LOCAL : ATM_ADDR_LECS));
> > 382 else
> > 383 error = atm_del_addr(dev, &addr,
> > 384 (cmd == ATM_DELADDR ?
> > 385 ATM_ADDR_LOCAL : ATM_ADDR_LECS));
> > 386 goto done;
> > 387 }
> > ... ...
> > ... ...
> >
> >
> >
>
>
next prev parent reply other threads:[~2012-12-03 15:48 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-21 4:29 [Suggestion] net/atm : for sprintf, need check the total write length whether larger than a page Chen Gang
2012-12-03 8:56 ` Chen Gang
2012-12-03 15:48 ` chas williams - CONTRACTOR [this message]
2012-12-05 1:28 ` Chen Gang
2012-12-04 3:46 ` Chas Williams (CONTRACTOR)
2012-12-05 1:26 ` Chen Gang
2012-12-05 3:57 ` Chas Williams (CONTRACTOR)
2012-12-05 4:56 ` Chen Gang
2012-12-05 5:40 ` Chen Gang
2012-12-05 5:59 ` Chen Gang
2012-12-05 14:55 ` chas williams - CONTRACTOR
2012-12-06 1:15 ` Chen Gang
2012-12-06 9:05 ` Chen Gang
2012-12-06 14:08 ` chas williams - CONTRACTOR
2012-12-07 1:07 ` Chen Gang
2012-12-10 1:39 ` Chen Gang
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