Add lsm_set_self_attr01 test

Verify that lsm_set_self_attr syscall is raising errors when invalid
data is provided.

Signed-off-by: Andrea Cervesato <[email protected]>

runtest/syscalls

@@ -761,6 +761,7 @@ lsm_get_self_attr02 lsm_get_self_attr02
 lsm_get_self_attr03 lsm_get_self_attr03
 lsm_list_modules01 lsm_list_modules01
 lsm_list_modules02 lsm_list_modules02
+lsm_set_self_attr01 lsm_set_self_attr01
 
 lstat01 lstat01
 lstat01_64 lstat01_64

testcases/kernel/syscalls/lsm/.gitignore

@@ -3,3 +3,4 @@ lsm_get_self_attr02
 lsm_get_self_attr03
 lsm_list_modules01
 lsm_list_modules02
+lsm_set_self_attr01

testcases/kernel/syscalls/lsm/lsm_set_self_attr01.c

@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2024 SUSE LLC Andrea Cervesato <[email protected]>
+ */
+
+/*\
+ * [Description]
+ *
+ * Verify that lsm_set_self_attr syscall is raising errors when invalid data is
+ * provided.
+ */
+
+#include "lsm_common.h"
+
+static struct lsm_ctx *ctx;
+static struct lsm_ctx *ctx_orig;
+static struct lsm_ctx *ctx_null;
+static uint32_t ctx_size;
+static uint32_t ctx_size_small;
+static uint32_t ctx_size_big;
+static uint32_t page_size;
+
+static struct tcase {
+	uint32_t attr;
+	struct lsm_ctx **ctx;
+	uint32_t *size;
+	uint32_t flags;
+	int exp_errno;
+	char *msg;
+} tcases[] = {
+	{
+		.attr = LSM_ATTR_CURRENT,
+		.ctx = &ctx_null,
+		.size = &ctx_size,
+		.exp_errno = EFAULT,
+		.msg = "ctx is NULL",
+	},
+	{
+		.attr = LSM_ATTR_CURRENT,
+		.ctx = &ctx,
+		.size = &ctx_size_small,
+		.exp_errno = EINVAL,
+		.msg = "size is too small",
+	},
+	{
+		.attr = LSM_ATTR_CURRENT,
+		.ctx = &ctx,
+		.size = &ctx_size_big,
+		.exp_errno = E2BIG,
+		.msg = "size is too big",
+	},
+	{
+		.attr = LSM_ATTR_CURRENT,
+		.ctx = &ctx,
+		.size = &ctx_size,
+		.flags = 1,
+		.exp_errno = EINVAL,
+		.msg = "flags must be zero",
+	},
+	{
+		.attr = LSM_ATTR_CURRENT | LSM_ATTR_EXEC,
+		.ctx = &ctx,
+		.size = &ctx_size,
+		.exp_errno = EINVAL,
+		.msg = "attr is overset",
+	}
+};
+
+static void run(unsigned int n)
+{
+	struct tcase *tc = &tcases[n];
+
+	/* just in case lsm_set_self_attr() pass , we won't change
+	 * LSM configuration for the following process
+	 */
+	memcpy(ctx, ctx_orig, sizeof(struct lsm_ctx));
+
+	ctx_size = page_size;
+	ctx_size_small = 1;
+	ctx_size_big = ctx_size + 1;
+
+	TST_EXP_FAIL(lsm_set_self_attr(tc->attr, *tc->ctx, *tc->size, tc->flags),
+	      tc->exp_errno,
+	      "%s", tc->msg);
+}
+
+static void setup(void)
+{
+	int ret;
+	uint32_t size;
+	int lsm_count = 0;
+
+	if (verify_enabled_lsm("selinux"))
+		lsm_count++;
+
+	if (verify_enabled_lsm("apparmor"))
+		lsm_count++;
+
+	if (verify_enabled_lsm("smack"))
+		lsm_count++;
+
+	if (!lsm_count)
+		tst_brk(TCONF, "LSM_ATTR_CURRENT is not supported by any LSM");
+
+	page_size = SAFE_SYSCONF(_SC_PAGESIZE);
+	size = page_size;
+
+	ret = lsm_get_self_attr(LSM_ATTR_CURRENT, ctx_orig, &size, 0);
+	if (ret < 0)
+		tst_brk(TBROK, "Can't read LSM current attribute");
+}
+
+static struct tst_test test = {
+	.test = run,
+	.setup = setup,
+	.tcnt = ARRAY_SIZE(tcases),
+	.bufs = (struct tst_buffers[]) {
+		{&ctx, .size = sizeof(struct lsm_ctx)},
+		{&ctx_orig, .size = sizeof(struct lsm_ctx)},
+		{}
+	},
+};