noexec: set comm field for noexecs

function                                             old     new   delta
set_task_comm                                          -      18     +18
tryexec                                              152     159      +7
pseudo_exec_argv                                     321     328      +7
main                                                 106      97      -9
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 3/2 up/down: 34/-13)             Total: 23 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 10 insertions, 3 deletions

diff --git a/libbb/appletlib.c b/libbb/appletlib.c
index fa28d433b..ce259446b 100644
--- a/libbb/appletlib.c
+++ b/libbb/appletlib.c
@@ -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);