| 1 | // Verify that use of longjmp() in a _FORTIFY_SOURCE'd library (without ASAN) |
| 2 | // is correctly intercepted such that the stack is unpoisoned. |
| 3 | // Note: it is essential that the external library is not built with ASAN, |
| 4 | // otherwise it would be able to unpoison the stack before use. |
| 5 | // |
| 6 | // RUN: %clang -DIS_LIBRARY -D_FORTIFY_SOURCE=2 -O2 %s -c -o %t.o |
| 7 | // RUN: %clang_asan -O2 %s %t.o -o %t |
| 8 | // RUN: %run %t |
| 9 | |
| 10 | #ifdef IS_LIBRARY |
| 11 | /* the library */ |
| 12 | #include <setjmp.h> |
| 13 | #include <assert.h> |
| 14 | #include <sanitizer/asan_interface.h> |
| 15 | |
| 16 | static jmp_buf jenv; |
| 17 | |
| 18 | void external_callme(void (*callback)(void)) { |
| 19 | if (setjmp(jenv) == 0) { |
| 20 | callback(); |
| 21 | } |
| 22 | } |
| 23 | |
| 24 | void external_longjmp(char *msg) { |
| 25 | longjmp(jenv, 1); |
| 26 | } |
| 27 | |
| 28 | void external_check_stack(void) { |
| 29 | char buf[256] = "" ; |
| 30 | for (int i = 0; i < 256; i++) { |
| 31 | assert(!__asan_address_is_poisoned(buf + i)); |
| 32 | } |
| 33 | } |
| 34 | #else |
| 35 | /* main program */ |
| 36 | extern void external_callme(void (*callback)(void)); |
| 37 | extern void external_longjmp(char *msg); |
| 38 | extern void external_check_stack(void); |
| 39 | |
| 40 | static void callback(void) { |
| 41 | char msg[16]; /* Note: this triggers addition of a redzone. */ |
| 42 | /* Note: msg is passed to prevent compiler optimization from removing it. */ |
| 43 | external_longjmp(msg); |
| 44 | } |
| 45 | |
| 46 | int main() { |
| 47 | external_callme(callback); |
| 48 | external_check_stack(); |
| 49 | return 0; |
| 50 | } |
| 51 | #endif |
| 52 | |