Terminate when both suid bit and filecaps are set

This commit is contained in:
Mykyta Holubakha 2017-05-10 02:51:28 +03:00
parent f736198c31
commit 93cf21fb9a

View file

@ -27,6 +27,7 @@
#include "stringop.h"
#include "sway.h"
#include "log.h"
#include "util.h"
static bool terminate_request = false;
static int exit_value = 0;
@ -209,6 +210,27 @@ static void security_sanity_check() {
#endif
}
static void executable_sanity_check() {
#ifdef __linux__
struct stat sb;
char *exe = realpath("/proc/self/exe", NULL);
stat(exe, &sb);
// We assume that cap_get_file returning NULL implies ENODATA
if (sb.st_mode & (S_ISUID|S_ISGID) && cap_get_file(exe)) {
sway_log(L_ERROR,
"sway executable has both the s(g)uid bit AND file caps set.");
sway_log(L_ERROR,
"This is strongly discouraged (and completely broken).");
sway_log(L_ERROR,
"Please clear one of them (either the suid bit, or the file caps).");
sway_log(L_ERROR,
"If unsure, strip the file caps.");
exit(EXIT_FAILURE);
}
free(exe);
#endif
}
int main(int argc, char **argv) {
static int verbose = 0, debug = 0, validate = 0;
@ -326,6 +348,7 @@ int main(int argc, char **argv) {
return 0;
}
executable_sanity_check();
#ifdef __linux__
bool suid = false;
if (getuid() != geteuid() || getgid() != getegid()) {