f2cf1cc71

Denys Vlasenko

2017-08-07

SUCCESS Duration: 144s

Subject

noexec: set comm field for noexecs

No binary (build failed)

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

(log yok)

include/libbb.h+5 -0

@@ -1116,6 +1116,11 @@ int run_nofork_applet(int applet_no, char **argv) FAST_FUNC;
	extern int find_applet_by_name(const char *name) FAST_FUNC;
	extern void run_applet_no_and_exit(int a, const char name, char *argv) NORETURN FAST_FUNC;
	#endif
+	#if defined(__linux__)
+	void set_task_comm(const char *comm) FAST_FUNC;
+	#else
+	# define set_task_comm(name) ((void)0)
+	#endif

	/* Helpers for daemonization.
	*

libbb/appletlib.c+10 -3

@@ -911,6 +911,14 @@ int busybox_main(int argc UNUSED_PARAM, char **argv)
	}
	# endif

+	#if defined(__linux__) && (NUM_APPLETS > 1)
+	void FAST_FUNC set_task_comm(const char *comm)
+	{
+	/* okay if too long (truncates) */
+	prctl(PR_SET_NAME, (long)comm, 0, 0, 0);
+	}
+	#endif
+
	# if NUM_APPLETS > 0
	void FAST_FUNC run_applet_no_and_exit(int applet_no, const char name, char *argv)
	{
@@ -1064,15 +1072,14 @@ int main(int argc UNUSED_PARAM, char **argv)
	applet_name++;
	applet_name = bb_basename(applet_name);

-	# if defined(__linux__)
	/* If we are a result of execv("/proc/self/exe"), fix ugly comm of "exe" */
	if (ENABLE_FEATURE_SH_STANDALONE
	\|\| ENABLE_FEATURE_PREFER_APPLETS
	\|\| !BB_MMU
	) {
-	prctl(PR_SET_NAME, (long)applet_name, 0, 0, 0);
+	if (NUM_APPLETS > 1)
+	set_task_comm(applet_name);
	}
-	# endif

	parse_config_file(); /* ...maybe, if FEATURE_SUID_CONFIG */
	run_applet_and_exit(applet_name, argv);

libbb/vfork_daemon_rexec.c+5 -2

@@ -175,8 +175,6 @@ int FAST_FUNC spawn_and_wait(char **argv)
	return wait4pid(rc);

	/* child */
-	//TODO: prctl(PR_SET_NAME, (long)argv[0], 0, 0, 0);? [think pidof, pgrep, pkill]
-	//Rewrite /proc/PID/cmdline? (need to save argv0 and length at init for this to work!)
	/* reset some state and run without execing */

	/* msg_eol = "\n"; - no caller needs this reinited yet */
@@ -185,6 +183,11 @@ int FAST_FUNC spawn_and_wait(char **argv)
	* init, or a NOFORK applet. But none of those call us
	* as of yet (and that should probably always stay true).
	*/
+	//TODO: think pidof, pgrep, pkill!
+	//set_task_comm() makes our pidof find NOEXECs (e.g. "yes >/dev/null"),
+	//but one from procps-ng-3.3.10 needs more!
+	//Rewrite /proc/PID/cmdline? (need to save argv0 and length at init for this to work!)
+	set_task_comm(argv[0]);
	/* xfunc_error_retval and applet_name are init by: */
	run_applet_no_and_exit(a, argv[0], argv);
	}

shell/ash.c+4 -1

@@ -7803,8 +7803,11 @@ tryexec(IF_FEATURE_SH_STANDALONE(int applet_no,) const char cmd, char *argv, c
	while (*envp)
	putenv(*envp++);
	popredir(/drop:/ 1);
-	//TODO: prctl(PR_SET_NAME, (long)argv[0], 0, 0, 0);? [think pidof, pgrep, pkill]
+	//TODO: think pidof, pgrep, pkill!
+	//set_task_comm() makes our pidof find NOEXECs (e.g. "yes >/dev/null"),
+	//but one from procps-ng-3.3.10 needs more!
	//Rewrite /proc/PID/cmdline? (need to save argv0 and length at init for this to work!)
+	set_task_comm(argv[0]);
	run_applet_no_and_exit(applet_no, cmd, argv);
	}
	/* re-exec ourselves with the new arguments */

shell/hush.c+4 -1

@@ -7387,8 +7387,11 @@ static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save,
	/* Without this, "rm -i FILE" can't be ^C'ed: */
	switch_off_special_sigs(G.special_sig_mask);
	debug_printf_exec("running applet '%s'\n", argv[0]);
-	//TODO: prctl(PR_SET_NAME, (long)argv[0], 0, 0, 0);? [think pidof, pgrep, pkill]
+	//TODO: think pidof, pgrep, pkill!
+	//set_task_comm() makes our pidof find NOEXECs (e.g. "yes >/dev/null"),
+	//but one from procps-ng-3.3.10 needs more!
	//Rewrite /proc/PID/cmdline? (need to save argv0 and length at init for this to work!)
+	set_task_comm(argv[0]);
	run_applet_no_and_exit(a, argv[0], argv);
	}
	# endif