1 /* Verify that backtrace does not deadlock on itself on memory corruption. 2 Copyright (C) 2015-2022 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <https://www.gnu.org/licenses/>. */ 18 19 #include <signal.h> 20 #include <stdlib.h> 21 22 #include <support/support.h> 23 #include <libc-diag.h> 24 25 #define SIZE 4096 26 27 /* Wrap free with a function to prevent gcc from optimizing it out. */ 28 static void 29 __attribute__((noinline)) call_free(void * ptr)30call_free (void *ptr) 31 { 32 free (ptr); 33 #if __GNUC_PREREQ (12, 0) 34 /* Ignore a valid warning about using a pointer made indeterminate 35 by a prior call to free(). */ 36 DIAG_IGNORE_NEEDS_COMMENT (12, "-Wuse-after-free"); 37 #endif 38 *(size_t *)(ptr - sizeof (size_t)) = 1; 39 #if __GNUC_PREREQ (12, 0) 40 DIAG_POP_NEEDS_COMMENT; 41 #endif 42 } 43 44 int do_test(void)45do_test (void) 46 { 47 void *ptr1 = malloc (SIZE); 48 void *ptr2 = malloc (SIZE); 49 50 /* Avoid unwanted output to TTY after an expected memory corruption. */ 51 ignore_stderr(); 52 53 call_free (ptr1); 54 ptr1 = malloc (SIZE); 55 56 /* Not reached. The return statement is to put ptr2 into use so that gcc 57 doesn't optimize out that malloc call. */ 58 return (ptr1 == ptr2); 59 } 60 61 #define EXPECTED_SIGNAL SIGABRT 62 #include <support/test-driver.c> 63