| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | /* Test for vfprintf nargs allocation overflow (BZ #13656). |
| 2 | Copyright (C) 2012-2015 Free Software Foundation, Inc. |
| 3 | This file is part of the GNU C Library. |
| 4 | Contributed by Kees Cook <keescook@chromium.org>, 2012. |
| 5 | |
| 6 | The GNU C Library is free software; you can redistribute it and/or |
| 7 | modify it under the terms of the GNU Lesser General Public |
| 8 | License as published by the Free Software Foundation; either |
| 9 | version 2.1 of the License, or (at your option) any later version. |
| 10 | |
| 11 | The GNU C Library is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | Lesser General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU Lesser General Public |
| 17 | License along with the GNU C Library; if not, see |
| 18 | <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #include <stdio.h> |
| 21 | #include <stdlib.h> |
| 22 | #include <stdint.h> |
| 23 | #include <unistd.h> |
| 24 | #include <inttypes.h> |
| 25 | #include <string.h> |
| 26 | #include <signal.h> |
| 27 | |
| 28 | static int |
| 29 | format_failed (const char *fmt, const char *expected) |
| 30 | { |
| 31 | char output[80]; |
| 32 | |
| 33 | printf ("%s : ", fmt); |
| 34 | |
| 35 | memset (output, 0, sizeof output); |
| 36 | /* Having sprintf itself detect a failure is good. */ |
| 37 | if (sprintf (output, fmt, 1, 2, 3, "test") > 0 |
| 38 | && strcmp (output, expected) != 0) |
| 39 | { |
| 40 | printf ("FAIL (output '%s' != expected '%s')\n", output, expected); |
| 41 | return 1; |
| 42 | } |
| 43 | puts ("ok"); |
| 44 | return 0; |
| 45 | } |
| 46 | |
| 47 | static int |
| 48 | do_test (void) |
| 49 | { |
| 50 | int rc = 0; |
| 51 | char buf[64]; |
| 52 | |
| 53 | /* Regular positionals work. */ |
| 54 | if (format_failed ("%1$d", "1") != 0) |
| 55 | rc = 1; |
| 56 | |
| 57 | /* Regular width positionals work. */ |
| 58 | if (format_failed ("%1$*2$d", " 1") != 0) |
| 59 | rc = 1; |
| 60 | |
| 61 | /* Positional arguments are constructed via read_int, so nargs can only |
| 62 | overflow on 32-bit systems. On 64-bit systems, it will attempt to |
| 63 | allocate a giant amount of memory and possibly crash, which is the |
| 64 | expected situation. Since the 64-bit behavior is arch-specific, only |
| 65 | test this on 32-bit systems. */ |
| 66 | if (sizeof (long int) == 4) |
| 67 | { |
| 68 | sprintf (buf, "%%1$d %%%" PRIdPTR "$d", |
| 69 | (intptr_t) (UINT32_MAX / sizeof (int))); |
| 70 | if (format_failed (buf, "1 %$d") != 0) |
| 71 | rc = 1; |
| 72 | } |
| 73 | |
| 74 | return rc; |
| 75 | } |
| 76 | |
| 77 | #define TEST_FUNCTION do_test () |
| 78 | #include "../test-skeleton.c" |