[LTP] [PATCH v5 1/3] syscalls/modify_ldt: Add lapi/ldt.h
rbm@suse.com
rbm@suse.com
Mon Mar 31 19:43:47 CEST 2025
From: Ricardo B. Marlière <rbm@suse.com>
Add a wrapper to modify_ldt which is used in a few tests and should be
reused.
Reviewed-by: Andrea Cervesato <andrea.cervesato@suse.com>
Signed-off-by: Ricardo B. Marlière <rbm@suse.com>
---
configure.ac | 1 -
include/lapi/ldt.h | 34 ++++++++++++++++++++++++++++++
testcases/cve/cve-2015-3290.c | 37 +++++++--------------------------
testcases/cve/cve-2017-17053.c | 10 ++++-----
testcases/kernel/syscalls/fork/fork05.c | 5 ++---
5 files changed, 48 insertions(+), 39 deletions(-)
diff --git a/configure.ac b/configure.ac
index 671079f3aa48c72866f69e7c545d3428ba87f931..b22f3eacdb1ccb764eae443ab1fb70afd971a14c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -46,7 +46,6 @@ AC_CHECK_DECLS([PR_CAPBSET_DROP, PR_CAPBSET_READ],,,[#include <sys/prctl.h>])
AC_CHECK_DECLS([SEM_STAT_ANY],,,[#include <sys/sem.h>])
AC_CHECK_HEADERS_ONCE([ \
- asm/ldt.h \
asm/prctl.h \
cpuid.h \
emmintrin.h \
diff --git a/include/lapi/ldt.h b/include/lapi/ldt.h
new file mode 100644
index 0000000000000000000000000000000000000000..bab5404457b959a5b44adbf6f458602c5121dbb8
--- /dev/null
+++ b/include/lapi/ldt.h
@@ -0,0 +1,34 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2025 SUSE LLC Ricardo B. Marlière <rbm@suse.com>
+ */
+
+#ifndef LAPI_LDT_H__
+#define LAPI_LDT_H__
+
+#include "config.h"
+#include "lapi/syscalls.h"
+#include <asm/ldt.h>
+
+static int modify_ldt(int func, void *ptr, unsigned long bytecount)
+{
+ return tst_syscall(__NR_modify_ldt, func, ptr, bytecount);
+}
+
+static int safe_modify_ldt(const char *file, const int lineno, int func,
+ void *ptr, unsigned long bytecount)
+{
+ int rval;
+
+ rval = modify_ldt(func, ptr, bytecount);
+ if (rval == -1)
+ tst_brk_(file, lineno, TBROK | TERRNO,
+ "modify_ldt(%d, %p, %lu)", func, ptr, bytecount);
+
+ return rval;
+}
+
+#define SAFE_MODIFY_LDT(func, ptr, bytecount) \
+ safe_modify_ldt(__FILE__, __LINE__, (func), (ptr), (bytecount))
+
+#endif /* LAPI_LDT_H__ */
diff --git a/testcases/cve/cve-2015-3290.c b/testcases/cve/cve-2015-3290.c
index 63e5d92c91b830cd8066a6a6c329461b72731f32..c1c513c7c652313a6778bbdc84f0140e530650dc 100644
--- a/testcases/cve/cve-2015-3290.c
+++ b/testcases/cve/cve-2015-3290.c
@@ -118,12 +118,10 @@ perhaps unsurprisingly.)
#include "tst_test.h"
#include "tst_timer.h"
-#if defined(__x86_64__) || defined(__i386__)
-
+#if defined(__i386__) || defined(__x86_64__)
#include <stdlib.h>
#include <stdio.h>
#include <inttypes.h>
-#include <asm/ldt.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <setjmp.h>
@@ -132,6 +130,7 @@ perhaps unsurprisingly.)
#include <sys/wait.h>
#include <linux/perf_event.h>
+#include "lapi/ldt.h"
#include "lapi/syscalls.h"
#include "tst_safe_pthread.h"
@@ -187,7 +186,7 @@ static int running = 1;
static void set_ldt(void)
{
/* Boring 16-bit data segment. */
- const struct user_desc data_desc = {
+ struct user_desc data_desc = {
.entry_number = 0,
.base_addr = 0,
.limit = 0xfffff,
@@ -199,27 +198,7 @@ static void set_ldt(void)
.useable = 0
};
- TEST(tst_syscall(__NR_modify_ldt, 1, &data_desc, sizeof(data_desc)));
-
- /*
- * The kernel intentionally casts modify_ldt() return value
- * to unsigned int to prevent sign extension to 64 bits. This may
- * result in syscall() returning the value as is instead of setting
- * errno and returning -1.
- */
- if (TST_RET > 0 && ((int)TST_RET) < 0) {
- tst_res(TINFO,
- "WARNING: Libc mishandled modify_ldt() return value");
- TST_ERR = -(int)TST_RET;
- TST_RET = -1;
- }
-
- if (TST_RET == -1 && TST_ERR == EINVAL) {
- tst_brk(TCONF | TTERRNO,
- "modify_ldt: 16-bit data segments are probably disabled");
- } else if (TST_RET != 0) {
- tst_brk(TBROK | TTERRNO, "modify_ldt");
- }
+ SAFE_MODIFY_LDT(1, &data_desc, sizeof(data_desc));
}
static void try_corrupt_stack(unsigned short *orig_ss)
@@ -528,8 +507,6 @@ static struct tst_test test = {
}
};
-#else /* defined(__x86_64__) || defined(__i386__) */
-
-TST_TEST_TCONF("not (i386 or x86_64)");
-
-#endif
+#else
+TST_TEST_TCONF("Test supported only on x86");
+#endif /* defined(__i386__) || defined(__x86_64__) */
diff --git a/testcases/cve/cve-2017-17053.c b/testcases/cve/cve-2017-17053.c
index fe7b6d694d6ffbbce863abc1672e03ae5f419df1..7ba22fa94cee57fcb0b0b60c2462d036cb4a40c5 100644
--- a/testcases/cve/cve-2017-17053.c
+++ b/testcases/cve/cve-2017-17053.c
@@ -16,8 +16,7 @@
#include "config.h"
#include "tst_test.h"
-#ifdef HAVE_ASM_LDT_H
-#include <asm/ldt.h>
+#if defined(__i386__) || defined(__x86_64__)
#include <pthread.h>
#include <signal.h>
#include <stdlib.h>
@@ -26,6 +25,7 @@
#include <unistd.h>
#include <stdio.h>
+#include "lapi/ldt.h"
#include "lapi/syscalls.h"
#define EXEC_USEC 5000000
@@ -109,7 +109,7 @@ void run_test(void)
struct user_desc desc = { .entry_number = 8191 };
install_sighandler();
- syscall(__NR_modify_ldt, 1, &desc, sizeof(desc));
+ SAFE_MODIFY_LDT(1, &desc, sizeof(desc));
for (;;) {
if (shm->do_exit)
@@ -164,5 +164,5 @@ static struct tst_test test = {
};
#else
-TST_TEST_TCONF("no asm/ldt.h header (only for i386 or x86_64)");
-#endif
+TST_TEST_TCONF("Test supported only on x86");
+#endif /* defined(__i386__) || defined(__x86_64__) */
diff --git a/testcases/kernel/syscalls/fork/fork05.c b/testcases/kernel/syscalls/fork/fork05.c
index 22edefc3686978fbb9453dffabfcbccb7ea6bb12..9aa12e16201dec8f3d2a4c99df83c4e5e25ef857 100644
--- a/testcases/kernel/syscalls/fork/fork05.c
+++ b/testcases/kernel/syscalls/fork/fork05.c
@@ -55,8 +55,7 @@
#if defined(__i386__)
-#include "lapi/syscalls.h"
-#include <asm/ldt.h>
+#include "lapi/ldt.h"
static void run(void)
{
@@ -76,7 +75,7 @@ static void run(void)
ldt0.seg_not_present = 0;
ldt0.useable = 1;
- tst_syscall(__NR_modify_ldt, 1, &ldt0, sizeof(ldt0));
+ SAFE_MODIFY_LDT(1, &ldt0, sizeof(ldt0));
asm volatile ("movw %w0, %%fs"::"q" (7));
asm volatile ("movl %%fs:0, %0":"=r" (lo));
--
2.49.0
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