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  • Committer: Package Import Robot
  • Author(s): John Rigby, John Rigby
  • Date: 2011-09-26 10:44:23 UTC
  • Revision ID: package-import@ubuntu.com-20110926104423-3o58a3c1bj7x00rs
Tags: 3.0.0-1007.9
https://launchpad.net/bugs/826021
[ John Rigby ]

Enable crypto modules and remove crypto-modules from
exclude-module files
LP: #826021

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Lines of Context:
fs/compat.c
1306
1306
        return do_sys_open(dfd, filename, flags, mode);
1307
1307
}
1308
1308
 
1309
 
/*
1310
 
 * compat_count() counts the number of arguments/envelopes. It is basically
1311
 
 * a copy of count() from fs/exec.c, except that it works with 32 bit argv
1312
 
 * and envp pointers.
1313
 
 */
1314
 
static int compat_count(compat_uptr_t __user *argv, int max)
1315
 
{
1316
 
        int i = 0;
1317
 
 
1318
 
        if (argv != NULL) {
1319
 
                for (;;) {
1320
 
                        compat_uptr_t p;
1321
 
 
1322
 
                        if (get_user(p, argv))
1323
 
                                return -EFAULT;
1324
 
                        if (!p)
1325
 
                                break;
1326
 
                        argv++;
1327
 
                        if (i++ >= max)
1328
 
                                return -E2BIG;
1329
 
 
1330
 
                        if (fatal_signal_pending(current))
1331
 
                                return -ERESTARTNOHAND;
1332
 
                        cond_resched();
1333
 
                }
1334
 
        }
1335
 
        return i;
1336
 
}
1337
 
 
1338
 
/*
1339
 
 * compat_copy_strings() is basically a copy of copy_strings() from fs/exec.c
1340
 
 * except that it works with 32 bit argv and envp pointers.
1341
 
 */
1342
 
static int compat_copy_strings(int argc, compat_uptr_t __user *argv,
1343
 
                                struct linux_binprm *bprm)
1344
 
{
1345
 
        struct page *kmapped_page = NULL;
1346
 
        char *kaddr = NULL;
1347
 
        unsigned long kpos = 0;
1348
 
        int ret;
1349
 
 
1350
 
        while (argc-- > 0) {
1351
 
                compat_uptr_t str;
1352
 
                int len;
1353
 
                unsigned long pos;
1354
 
 
1355
 
                if (get_user(str, argv+argc) ||
1356
 
                    !(len = strnlen_user(compat_ptr(str), MAX_ARG_STRLEN))) {
1357
 
                        ret = -EFAULT;
1358
 
                        goto out;
1359
 
                }
1360
 
 
1361
 
                if (len > MAX_ARG_STRLEN) {
1362
 
                        ret = -E2BIG;
1363
 
                        goto out;
1364
 
                }
1365
 
 
1366
 
                /* We're going to work our way backwords. */
1367
 
                pos = bprm->p;
1368
 
                str += len;
1369
 
                bprm->p -= len;
1370
 
 
1371
 
                while (len > 0) {
1372
 
                        int offset, bytes_to_copy;
1373
 
 
1374
 
                        if (fatal_signal_pending(current)) {
1375
 
                                ret = -ERESTARTNOHAND;
1376
 
                                goto out;
1377
 
                        }
1378
 
                        cond_resched();
1379
 
 
1380
 
                        offset = pos % PAGE_SIZE;
1381
 
                        if (offset == 0)
1382
 
                                offset = PAGE_SIZE;
1383
 
 
1384
 
                        bytes_to_copy = offset;
1385
 
                        if (bytes_to_copy > len)
1386
 
                                bytes_to_copy = len;
1387
 
 
1388
 
                        offset -= bytes_to_copy;
1389
 
                        pos -= bytes_to_copy;
1390
 
                        str -= bytes_to_copy;
1391
 
                        len -= bytes_to_copy;
1392
 
 
1393
 
                        if (!kmapped_page || kpos != (pos & PAGE_MASK)) {
1394
 
                                struct page *page;
1395
 
 
1396
 
                                page = get_arg_page(bprm, pos, 1);
1397
 
                                if (!page) {
1398
 
                                        ret = -E2BIG;
1399
 
                                        goto out;
1400
 
                                }
1401
 
 
1402
 
                                if (kmapped_page) {
1403
 
                                        flush_kernel_dcache_page(kmapped_page);
1404
 
                                        kunmap(kmapped_page);
1405
 
                                        put_page(kmapped_page);
1406
 
                                }
1407
 
                                kmapped_page = page;
1408
 
                                kaddr = kmap(kmapped_page);
1409
 
                                kpos = pos & PAGE_MASK;
1410
 
                                flush_cache_page(bprm->vma, kpos,
1411
 
                                                 page_to_pfn(kmapped_page));
1412
 
                        }
1413
 
                        if (copy_from_user(kaddr+offset, compat_ptr(str),
1414
 
                                                bytes_to_copy)) {
1415
 
                                ret = -EFAULT;
1416
 
                                goto out;
1417
 
                        }
1418
 
                }
1419
 
        }
1420
 
        ret = 0;
1421
 
out:
1422
 
        if (kmapped_page) {
1423
 
                flush_kernel_dcache_page(kmapped_page);
1424
 
                kunmap(kmapped_page);
1425
 
                put_page(kmapped_page);
1426
 
        }
1427
 
        return ret;
1428
 
}
1429
 
 
1430
 
/*
1431
 
 * compat_do_execve() is mostly a copy of do_execve(), with the exception
1432
 
 * that it processes 32 bit argv and envp pointers.
1433
 
 */
1434
 
int compat_do_execve(char * filename,
1435
 
        compat_uptr_t __user *argv,
1436
 
        compat_uptr_t __user *envp,
1437
 
        struct pt_regs * regs)
1438
 
{
1439
 
        struct linux_binprm *bprm;
1440
 
        struct file *file;
1441
 
        struct files_struct *displaced;
1442
 
        bool clear_in_exec;
1443
 
        int retval;
1444
 
 
1445
 
        retval = unshare_files(&displaced);
1446
 
        if (retval)
1447
 
                goto out_ret;
1448
 
 
1449
 
        retval = -ENOMEM;
1450
 
        bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
1451
 
        if (!bprm)
1452
 
                goto out_files;
1453
 
 
1454
 
        retval = prepare_bprm_creds(bprm);
1455
 
        if (retval)
1456
 
                goto out_free;
1457
 
 
1458
 
        retval = check_unsafe_exec(bprm);
1459
 
        if (retval < 0)
1460
 
                goto out_free;
1461
 
        clear_in_exec = retval;
1462
 
        current->in_execve = 1;
1463
 
 
1464
 
        file = open_exec(filename);
1465
 
        retval = PTR_ERR(file);
1466
 
        if (IS_ERR(file))
1467
 
                goto out_unmark;
1468
 
 
1469
 
        sched_exec();
1470
 
 
1471
 
        bprm->file = file;
1472
 
        bprm->filename = filename;
1473
 
        bprm->interp = filename;
1474
 
 
1475
 
        retval = bprm_mm_init(bprm);
1476
 
        if (retval)
1477
 
                goto out_file;
1478
 
 
1479
 
        bprm->argc = compat_count(argv, MAX_ARG_STRINGS);
1480
 
        if ((retval = bprm->argc) < 0)
1481
 
                goto out;
1482
 
 
1483
 
        bprm->envc = compat_count(envp, MAX_ARG_STRINGS);
1484
 
        if ((retval = bprm->envc) < 0)
1485
 
                goto out;
1486
 
 
1487
 
        retval = prepare_binprm(bprm);
1488
 
        if (retval < 0)
1489
 
                goto out;
1490
 
 
1491
 
        retval = copy_strings_kernel(1, &bprm->filename, bprm);
1492
 
        if (retval < 0)
1493
 
                goto out;
1494
 
 
1495
 
        bprm->exec = bprm->p;
1496
 
        retval = compat_copy_strings(bprm->envc, envp, bprm);
1497
 
        if (retval < 0)
1498
 
                goto out;
1499
 
 
1500
 
        retval = compat_copy_strings(bprm->argc, argv, bprm);
1501
 
        if (retval < 0)
1502
 
                goto out;
1503
 
 
1504
 
        retval = search_binary_handler(bprm, regs);
1505
 
        if (retval < 0)
1506
 
                goto out;
1507
 
 
1508
 
        /* execve succeeded */
1509
 
        current->fs->in_exec = 0;
1510
 
        current->in_execve = 0;
1511
 
        acct_update_integrals(current);
1512
 
        free_bprm(bprm);
1513
 
        if (displaced)
1514
 
                put_files_struct(displaced);
1515
 
        return retval;
1516
 
 
1517
 
out:
1518
 
        if (bprm->mm) {
1519
 
                acct_arg_size(bprm, 0);
1520
 
                mmput(bprm->mm);
1521
 
        }
1522
 
 
1523
 
out_file:
1524
 
        if (bprm->file) {
1525
 
                allow_write_access(bprm->file);
1526
 
                fput(bprm->file);
1527
 
        }
1528
 
 
1529
 
out_unmark:
1530
 
        if (clear_in_exec)
1531
 
                current->fs->in_exec = 0;
1532
 
        current->in_execve = 0;
1533
 
 
1534
 
out_free:
1535
 
        free_bprm(bprm);
1536
 
 
1537
 
out_files:
1538
 
        if (displaced)
1539
 
                reset_files_struct(displaced);
1540
 
out_ret:
1541
 
        return retval;
1542
 
}
1543
 
 
1544
1309
#define __COMPAT_NFDBITS       (8 * sizeof(compat_ulong_t))
1545
1310
 
1546
1311
static int poll_select_copy_remaining(struct timespec *end_time, void __user *p,