1 files changed, 143 insertions, 0 deletions
diff --git a/src/kernel/tests/lib/tst_buffers.c b/src/kernel/tests/lib/tst_buffers.c
new file mode 100644
index 0000000..b8b597a
--- /dev/null
+++ b/src/kernel/tests/lib/tst_buffers.c
@@ -0,0 +1,143 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2019 Cyril Hrubis <chrubis@suse.cz>
+ */
+
+#include <sys/mman.h>
+#include <stdlib.h>
+#define TST_NO_DEFAULT_MAIN
+#include "tst_test.h"
+
+struct map {
+	void *addr;
+	size_t size;
+	size_t buf_shift;
+	struct map *next;
+};
+
+static struct map *maps;
+
+static void setup_canary(struct map *map)
+{
+	size_t i;
+	char *buf = map->addr;
+
+	for (i = 0; i < map->buf_shift/2; i++) {
+		char c = random();
+		buf[map->buf_shift - i - 1] = c;
+		buf[i] = c;
+	}
+}
+
+static void check_canary(struct map *map)
+{
+	size_t i;
+	char *buf = map->addr;
+
+	for (i = 0; i < map->buf_shift/2; i++) {
+		if (buf[map->buf_shift - i - 1] != buf[i]) {
+			tst_res(TWARN,
+				"pid %i: buffer modified address %p[%zi]",
+				getpid(), (char*)map->addr + map->buf_shift, -i-1);
+		}
+	}
+}
+
+void *tst_alloc(size_t size)
+{
+	size_t page_size = getpagesize();
+	unsigned int pages = (size / page_size) + !!(size % page_size) + 1;
+	void *ret;
+	struct map *map = SAFE_MALLOC(sizeof(struct map));
+	static int print_msg = 1;
+
+	if (print_msg) {
+		tst_res(TINFO, "Test is using guarded buffers");
+		print_msg = 0;
+	}
+
+	ret = SAFE_MMAP(NULL, page_size * pages, PROT_READ | PROT_WRITE,
+	                MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+
+	mprotect(ret + (pages-1) * page_size, page_size, PROT_NONE);
+
+	map->addr = ret;
+	map->size = pages * page_size;
+	map->next = maps;
+	maps = map;
+
+	if (size % page_size)
+		map->buf_shift = page_size - (size % page_size);
+	else
+		map->buf_shift = 0;
+
+	setup_canary(map);
+
+	return ret + map->buf_shift;
+}
+
+static int count_iovec(int *sizes)
+{
+	int ret = 0;
+
+	while (sizes[ret++] != -1);
+
+	return ret - 1;
+}
+
+struct iovec *tst_iovec_alloc(int sizes[])
+{
+	int i, cnt = count_iovec(sizes);
+	struct iovec *iovec;
+
+	if (cnt <= 0)
+		return NULL;
+
+	iovec = tst_alloc(sizeof(struct iovec) * cnt);
+
+	for (i = 0; i < cnt; i++) {
+		if (sizes[i]) {
+			iovec[i].iov_base = tst_alloc(sizes[i]);
+			iovec[i].iov_len = sizes[i];
+		} else {
+			iovec[i].iov_base = NULL;
+			iovec[i].iov_base = 0;
+		}
+	}
+
+	return iovec;
+}
+
+void tst_buffers_alloc(struct tst_buffers bufs[])
+{
+	unsigned int i;
+
+	for (i = 0; bufs[i].ptr; i++) {
+		if (bufs[i].size)
+			*((void**)bufs[i].ptr) = tst_alloc(bufs[i].size);
+		else
+			*((void**)bufs[i].ptr) = tst_iovec_alloc(bufs[i].iov_sizes);
+	}
+}
+
+char *tst_strdup(const char *str)
+{
+	size_t len = strlen(str);
+	char *ret = tst_alloc(len + 1);
+	return strcpy(ret, str);
+}
+
+void tst_free_all(void)
+{
+	struct map *i = maps;
+
+	while (i) {
+		struct map *j = i;
+		check_canary(i);
+		SAFE_MUNMAP(i->addr, i->size);
+		i = i->next;
+		free(j);
+	}
+
+	maps = NULL;
+}