Terminate when both suid bit and filecaps are set
#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()) {
