1 /*
2 * Distributed under the terms of the GNU Lesser General Public License
3 * $Header: $
4 *
5 * This is a modified version of Hiroaki Etoh's stack smashing routines
6 * implemented for glibc.
7 *
8 * The following people have contributed input to this code.
9 * Ned Ludd - <solar[@]gentoo.org>
10 * Alexander Gabert - <pappy[@]gentoo.org>
11 * The PaX Team - <pageexec[@]freemail.hu>
12 * Peter S. Mazinger - <ps.m[@]gmx.net>
13 * Yoann Vandoorselaere - <yoann[@]prelude-ids.org>
14 * Robert Connolly - <robert[@]linuxfromscratch.org>
15 * Cory Visi <cory[@]visi.name>
16 * Mike Frysinger <vapier[@]gentoo.org>
17 */
18
19 #if defined __SSP__ || defined __SSP_ALL__
20 #error "file must not be compiled with stack protection enabled on it. Use -fno-stack-protector"
21 #endif
22
23 #include <string.h>
24 #include <unistd.h>
25 #include <signal.h>
26 #ifdef __UCLIBC_HAS_SYSLOG__
27 #include <sys/syslog.h>
28 #endif
29
30 #ifdef __PROPOLICE_BLOCK_SEGV__
31 # define SSP_SIGTYPE SIGSEGV
32 #else
33 # define SSP_SIGTYPE SIGABRT
34 #endif
35
do_write(const char * msg)36 static void do_write(const char *msg)
37 {
38 /* could use inlined syscall here to be sure ... */
39 return (void) write(STDERR_FILENO, msg, strlen(msg));
40 }
41
do_msg(const char * msg1,const char * msg2,const char * msg3)42 static void __cold do_msg(const char *msg1, const char *msg2, const char *msg3)
43 {
44 do_write(msg1);
45 do_write(msg2);
46 do_write(msg3);
47 do_write("\n");
48 #ifdef __UCLIBC_HAS_SYSLOG__
49 syslog(LOG_INFO, "%s%s%s()", msg1, msg2, msg3);
50 #endif
51 }
52
53 static void __cold attribute_noreturn
ssp_handler(void)54 ssp_handler(void)
55 {
56 pid_t pid;
57 static const char msg_ssd[] = "*** stack smashing detected ***: ";
58 static const char msg_terminated[] = " terminated";
59
60 #ifdef __DODEBUG__
61 struct sigaction sa;
62 sigset_t mask;
63
64 __sigfillset(&mask);
65 __sigdelset(&mask, SSP_SIGTYPE); /* Block all signal handlers */
66 sigprocmask(SIG_BLOCK, &mask, NULL); /* except SSP_SIGTYPE */
67 #endif
68
69 do_msg(msg_ssd, __uclibc_progname, msg_terminated);
70
71 pid = getpid();
72 #ifdef __DODEBUG__
73 /* Make the default handler associated with the signal handler */
74 memset(&sa, 0, sizeof(sa));
75 __sigfillset(&sa.sa_mask); /* Block all signals */
76 if (SIG_DFL) /* if it's constant zero, it's already done */
77 sa.sa_handler = SIG_DFL;
78 if (sigaction(SSP_SIGTYPE, &sa, NULL) == 0)
79 (void)kill(pid, SSP_SIGTYPE);
80 #endif
81 (void)kill(pid, SIGKILL);
82 /* The loop is added only to keep gcc happy. */
83 while(1)
84 _exit(127);
85 }
86
87 strong_alias(ssp_handler,__stack_chk_fail)
88