[LTP] [PATCH v5 2/3] syscalls/modify_ldt02: Refactor into new API
rbm@suse.com
rbm@suse.com
Mon Mar 31 19:43:48 CEST 2025
From: Ricardo B. Marlière <rbm@suse.com>
Reviewed-by: Andrea Cervesato <andrea.cervesato@suse.com>
Signed-off-by: Ricardo B. Marlière <rbm@suse.com>
---
testcases/kernel/syscalls/modify_ldt/common.h | 30 +++
.../kernel/syscalls/modify_ldt/modify_ldt02.c | 223 +++++----------------
2 files changed, 80 insertions(+), 173 deletions(-)
diff --git a/testcases/kernel/syscalls/modify_ldt/common.h b/testcases/kernel/syscalls/modify_ldt/common.h
new file mode 100644
index 0000000000000000000000000000000000000000..40e33251528dc3352c39c221f26bb91733424162
--- /dev/null
+++ b/testcases/kernel/syscalls/modify_ldt/common.h
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) International Business Machines Corp., 2001
+ * 07/2001 Ported by Wayne Boyer
+ * Copyright (c) 2025 SUSE LLC Ricardo B. Marlière <rbm@suse.com>
+ */
+
+#ifndef COMMON_H
+#define COMMON_H
+
+#include "tst_test.h"
+#include "lapi/ldt.h"
+
+int create_segment(void *seg, size_t size)
+{
+ struct user_desc entry = {
+ .entry_number = 0,
+ .base_addr = (unsigned long)seg,
+ .limit = size,
+ .seg_32bit = 1,
+ .contents = 0,
+ .read_exec_only = 0,
+ .limit_in_pages = 0,
+ .seg_not_present = 0,
+ };
+
+ return SAFE_MODIFY_LDT(1, &entry, sizeof(entry));
+}
+
+#endif
diff --git a/testcases/kernel/syscalls/modify_ldt/modify_ldt02.c b/testcases/kernel/syscalls/modify_ldt/modify_ldt02.c
index 5113b3fb4e29d241e819e98c90c297107aec93cf..f3dc2f6b02d6cf96354b8184cae1b738294640c0 100644
--- a/testcases/kernel/syscalls/modify_ldt/modify_ldt02.c
+++ b/testcases/kernel/syscalls/modify_ldt/modify_ldt02.c
@@ -1,199 +1,76 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
- *
- * 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
+ * Copyright (c) International Business Machines Corp., 2001
* 07/2001 Ported by Wayne Boyer
- *
- * RESTRICTIONS
- * None
+ * Copyright (c) 2025 SUSE LLC Ricardo B. Marlière <rbm@suse.com>
*/
-#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);
-
-int main(int ac, char **av)
-{
- int lc;
-
- int val, pid, status;
-
- int seg[4];
-
- tst_parse_opts(ac, av, NULL, NULL);
-
- setup();
-
- for (lc = 0; TEST_LOOPING(lc); lc++) {
- tst_count = 0;
-
- seg[0] = 12345;
- if (create_segment(seg, sizeof(seg)) == -1) {
- tst_brkm(TBROK, 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]);
- } else
- tst_resm(TPASS, "value read as expected");
-
- if (create_segment(0, 10) == -1) {
- tst_brkm(TBROK, cleanup, "Creation of segment failed");
- }
-
- tst_old_flush();
- if ((pid = tst_fork()) == 0) {
- signal(SIGSEGV, SIG_DFL);
- val = read_segment(0);
- exit(1);
- }
-
- (void)waitpid(pid, &status, 0);
-
- if (WEXITSTATUS(status) != 0) {
- tst_resm(TFAIL, "Did not generate SEGV, child returned "
- "unexpected status");
- } else {
- if (WIFSIGNALED(status) && (WTERMSIG(status) == SIGSEGV))
- tst_resm(TPASS, "generate SEGV as expected");
- else
- tst_resm(TFAIL, "Did not generate SEGV");
- }
- }
- cleanup();
- tst_exit();
+/*\
+ * Verify that after writing an invalid base address into a segment entry,
+ * a subsequent segment entry read will raise SIGSEV.
+ */
-}
+#include "tst_test.h"
-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));
-}
+#ifdef __i386__
+#include "common.h"
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)));
+ movl %%fs:(%1), %0"
+ : "=r"(res)
+ : "r"(index * sizeof(int)));
+
return res;
}
-void setup(void)
+void run_child(void)
{
- tst_sig(FORK, DEF_HANDLER, cleanup);
+ int val;
- TEST_PAUSE;
+ signal(SIGSEGV, SIG_DFL);
+ val = read_segment(0);
+ exit(1);
}
-void cleanup(void)
+void run(void)
{
+ int pid, status, seg[4];
-}
-#elif HAVE_MODIFY_LDT
-int main(void)
-{
- tst_brkm(TCONF,
- NULL,
- "modify_ldt is available but not tested on the platform than __i386__");
-}
+ seg[0] = 12345;
-#else /* if defined(__i386__) */
+ create_segment(seg, sizeof(seg));
-int main(void)
-{
- tst_resm(TINFO, "modify_ldt02 test only for ix86");
- tst_exit();
+ TST_EXP_EQ_LI(read_segment(0), seg[0]);
+
+ create_segment(0, 10);
+
+ pid = SAFE_FORK();
+ if (!pid)
+ run_child();
+
+ SAFE_WAITPID(pid, &status, 0);
+ if (WEXITSTATUS(status) != 0) {
+ tst_res(TFAIL, "Did not generate SEGV, child returned "
+ "unexpected status");
+ } else {
+ if (WIFSIGNALED(status) && (WTERMSIG(status) == SIGSEGV))
+ tst_res(TPASS, "generate SEGV as expected");
+ else
+ tst_res(TFAIL, "Did not generate SEGV");
+ }
}
-#endif /* if defined(__i386__) */
+static struct tst_test test = {
+ .test_all = run,
+ .forks_child = 1,
+};
+
+#else
+TST_TEST_TCONF("Test supported only on i386");
+#endif /* __i386__ */
--
2.49.0
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