| /* |
| * |
| * Copyright (c) International Business Machines Corp., 2001 |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| * the GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /* |
| * NAME |
| * modify_ldt02.c |
| * |
| * DESCRIPTION |
| * Testcase to check the error conditions for modify_ldt(2) |
| * |
| * ALGORITHM |
| * block1: |
| * Create a segment at entry 0 and a valid base address. |
| * Read the contents of the segment thru' fs register. |
| * Validate the data. |
| * Write an invalid base address into entry 0. |
| * Read the contents of entry 0 in the child process. |
| * Verify that a SIGSEGV is incurred. |
| * |
| * USAGE |
| * modify_ldt02 |
| * |
| * HISTORY |
| * 07/2001 Ported by Wayne Boyer |
| * |
| * RESTRICTIONS |
| * None |
| */ |
| |
| #include "config.h" |
| #include "test.h" |
| |
| TCID_DEFINE(modify_ldt02); |
| int TST_TOTAL = 1; |
| |
| #if defined(__i386__) && defined(HAVE_MODIFY_LDT) |
| |
| #ifdef HAVE_ASM_LDT_H |
| #include <asm/ldt.h> |
| #endif |
| extern int modify_ldt(int, void *, unsigned long); |
| |
| #include <asm/unistd.h> |
| #include <string.h> |
| #include <sys/wait.h> |
| #include <errno.h> |
| |
| /* Newer ldt.h files use user_desc, instead of modify_ldt_ldt_s */ |
| #ifdef HAVE_STRUCT_USER_DESC |
| typedef struct user_desc modify_ldt_s; |
| #elif HAVE_STRUCT_MODIFY_LDT_LDT_S |
| typedef struct modify_ldt_ldt_s modify_ldt_s; |
| #else |
| typedef struct modify_ldt_ldt_t { |
| unsigned int entry_number; |
| unsigned long int base_addr; |
| unsigned int limit; |
| unsigned int seg_32bit:1; |
| unsigned int contents:2; |
| unsigned int read_exec_only:1; |
| unsigned int limit_in_pages:1; |
| unsigned int seg_not_present:1; |
| unsigned int useable:1; |
| unsigned int empty:25; |
| } modify_ldt_s; |
| #endif |
| |
| int create_segment(void *, size_t); |
| int read_segment(unsigned int); |
| void cleanup(void); |
| void setup(void); |
| |
| #define FAILED 1 |
| |
| int main(int ac, char **av) |
| { |
| int lc; |
| const char *msg; |
| |
| int val, pid, status; |
| |
| int flag; |
| int seg[4]; |
| |
| if ((msg = parse_opts(ac, av, NULL, NULL)) != NULL) { |
| tst_brkm(TBROK, NULL, "OPTION PARSING ERROR - %s", msg); |
| } |
| |
| setup(); /* global setup */ |
| |
| /* The following loop checks looping state if -i option given */ |
| for (lc = 0; TEST_LOOPING(lc); lc++) { |
| |
| /* reset tst_count in case we are looping */ |
| tst_count = 0; |
| |
| //block1: |
| tst_resm(TINFO, "Enter block 1"); |
| flag = 0; |
| |
| seg[0] = 12345; |
| if (create_segment(seg, sizeof(seg)) == -1) { |
| tst_brkm(TINFO, cleanup, "Creation of segment failed"); |
| } |
| |
| val = read_segment(0); |
| |
| if (val != seg[0]) { |
| tst_resm(TFAIL, "Invalid value read %d, expected %d", |
| val, seg[0]); |
| flag = FAILED; |
| } |
| |
| if (flag) { |
| tst_resm(TINFO, "block 1 FAILED"); |
| } else { |
| tst_resm(TINFO, "block 1 PASSED"); |
| } |
| |
| tst_resm(TINFO, "Exit block 1"); |
| |
| //block2: |
| tst_resm(TINFO, "Enter block 2"); |
| flag = 0; |
| |
| if (create_segment(0, 10) == -1) { |
| tst_brkm(TINFO, cleanup, "Creation of segment failed"); |
| } |
| |
| tst_flush(); |
| if ((pid = FORK_OR_VFORK()) == 0) { |
| val = read_segment(0); |
| exit(1); |
| } |
| |
| (void)waitpid(pid, &status, 0); |
| |
| if (WEXITSTATUS(status) != 0) { |
| flag = FAILED; |
| tst_resm(TFAIL, "Did not generate SEGV, child returned " |
| "unexpected status"); |
| } |
| |
| if (flag) { |
| tst_resm(TINFO, "block 2 FAILED"); |
| } else { |
| tst_resm(TINFO, "block 2 PASSED"); |
| } |
| } |
| cleanup(); |
| tst_exit(); |
| |
| } |
| |
| int create_segment(void *seg, size_t size) |
| { |
| modify_ldt_s entry; |
| |
| entry.entry_number = 0; |
| entry.base_addr = (unsigned long)seg; |
| entry.limit = size; |
| entry.seg_32bit = 1; |
| entry.contents = 0; |
| entry.read_exec_only = 0; |
| entry.limit_in_pages = 0; |
| entry.seg_not_present = 0; |
| |
| return modify_ldt(1, &entry, sizeof(entry)); |
| } |
| |
| int read_segment(unsigned int index) |
| { |
| int res; |
| __asm__ __volatile__("\n\ |
| push $0x0007;\n\ |
| pop %%fs;\n\ |
| movl %%fs:(%1), %0":"=r"(res) |
| :"r"(index * sizeof(int))); |
| return res; |
| } |
| |
| void sigsegv_handler(int sig) |
| { |
| tst_resm(TINFO, "received signal: %d", sig); |
| exit(0); |
| } |
| |
| /* |
| * setup() - performs all ONE TIME setup for this test |
| */ |
| void setup(void) |
| { |
| struct sigaction act; |
| |
| memset(&act, 0, sizeof(act)); |
| sigemptyset(&act.sa_mask); |
| |
| tst_sig(FORK, DEF_HANDLER, cleanup); |
| |
| act.sa_handler = sigsegv_handler; |
| (void)sigaction(SIGSEGV, &act, NULL); |
| |
| TEST_PAUSE; |
| } |
| |
| /* |
| * cleanup() - performs all the ONE TIME cleanup for this test at completion |
| * or premature exit. |
| */ |
| void cleanup(void) |
| { |
| |
| } |
| #elif HAVE_MODIFY_LDT |
| int main(void) |
| { |
| tst_brkm(TCONF, |
| NULL, |
| "modify_ldt is available but not tested on the platform than __i386__"); |
| } |
| |
| #else /* if defined(__i386__) */ |
| |
| int main(void) |
| { |
| tst_resm(TINFO, "modify_ldt02 test only for ix86"); |
| tst_exit(); |
| } |
| |
| #endif /* if defined(__i386__) */ |