feat: created initial stack smash protector

CMakeLists.txt

@@ -10,7 +10,7 @@ SET(CMAKE_ASM_COMPILER ${COMPILER_RT}/i686-elf-gcc)
 #SET(CMAKE_VERBOSE_MAKEFILE ON)
 
 # Set compile flags
-SET(CMAKE_C_FLAGS "-g -ffreestanding -Wall -Wextra -fno-exceptions -fno-stack-protector -fno-pie -m32")
+SET(CMAKE_C_FLAGS "-g -ffreestanding -Wall -Wextra -fno-exceptions -fstack-protector -fno-pie -m32")
 SET(CMAKE_ASM_FLAGS "${CFLAGS} -m32 -x assembler-with-cpp")
 SET(CMAKE_EXE_LINKER_FLAGS "-T${CMAKE_CURRENT_LIST_DIR}/linker.ld -lgcc -ffreestanding -nostdlib -no-pie")
 

include/stdlib.h

@@ -15,7 +15,7 @@
 #error "Userspace not implemented"
 #endif
 
-void abort();
+void __attribute__((__noreturn__)) abort();
 
 int atexit(void (*)(void));
 

kernel/command.c

@@ -54,6 +54,8 @@ void explode(const char *args);
 
 void exec_self_test(const char *args);
 
+void smash(const char *args);
+
 #endif
 
 cmd_handler cmd_handlers[] = {
@@ -65,10 +67,16 @@ cmd_handler cmd_handlers[] = {
         {"explode", explode},
 #ifdef ENABLE_SELF_TEST
         {"self-test", exec_self_test},
+        {"smash", smash},
 #endif
         {NULL, NULL},
 };
 
+void smash(const char* args) {
+    char data[16];
+    memset(data, 'A', 32);
+}
+
 void exec_self_test(const char *args) {
     self_test();
 }

kernel/debug/self_test.c

@@ -84,7 +84,7 @@ void test_string() {
     assert_array_all_entries(array_b, 0, 8);
     assert_array_all_entries(array_b + 8, 1, 8);
     memcpy(array_b + 8, array_a, 8);
-    assert_array_all_entries(array_b + 8, 0, 16);
+    assert_array_all_entries(array_b, 0, 16);
 
     // strlen
     assert_int(3, strlen("abc"));

kernel/util/ssp.c

@@ -0,0 +1,29 @@
+//
+// Created by rick on 15-03-21.
+//
+// stack smashing protector
+
+#include <stdint.h>
+#if __STDC_HOSTED__
+#include <stdlib.h>
+#else
+#include <myke/libk/libk.h>
+#endif
+
+#if UINT32_MAX == UINTPTR_MAX
+#define STACK_CHK_GUARD 0xe2dee396
+#else
+#define STACK_CHK_GUARD 0x595e9fbd94fda766
+#endif
+
+// todo this value should be unique every time the kernel starts
+uintptr_t __stack_chk_guard = STACK_CHK_GUARD;
+
+void __attribute__((__noreturn__)) __stack_chk_fail(void) {
+#if __STDC_HOSTED__
+#error "UNKNONONO"
+    abort();
+#else
+    k_panics("Stack Smashed!");
+#endif
+}