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// Verify that use of longjmp() in a _FORTIFY_SOURCE'd library (without ASAN)
// is correctly intercepted such that the stack is unpoisoned.
// Note: it is essential that the external library is not built with ASAN,
// otherwise it would be able to unpoison the stack before use.
//
// RUN: %clang -DIS_LIBRARY -D_FORTIFY_SOURCE=2 -O2 %s -c -o %t.o
// RUN: %clang_asan -O2 %s %t.o -o %t
// RUN: %run %t
#ifdef IS_LIBRARY
/* the library */
#include <setjmp.h>
#include <assert.h>
#include <sanitizer/asan_interface.h>
static jmp_buf jenv;
void external_callme(void (*callback)(void)) {
if (setjmp(jenv) == 0) {
callback();
}
}
void external_longjmp(char *msg) {
longjmp(jenv, 1);
}
void external_check_stack(void) {
char buf[256] = "";
for (int i = 0; i < 256; i++) {
assert(!__asan_address_is_poisoned(buf + i));
}
}
#else
/* main program */
extern void external_callme(void (*callback)(void));
extern void external_longjmp(char *msg);
extern void external_check_stack(void);
static void callback(void) {
char msg[16]; /* Note: this triggers addition of a redzone. */
/* Note: msg is passed to prevent compiler optimization from removing it. */
external_longjmp(msg);
}
int main() {
external_callme(callback);
external_check_stack();
return 0;
}
#endif
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