libbb: make BB_EXECVP/LP try to exec real binary if there's no /proc/self/exe

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

3 files changed, 18 insertions, 16 deletions

diff --git a/include/libbb.h b/include/libbb.h
index 182b47988..e69e27944 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -867,14 +867,16 @@ int exists_execable(const char *filename) FAST_FUNC;
  * but it may exec busybox and call applet instead of searching PATH.
  */
 #if ENABLE_FEATURE_PREFER_APPLETS
-int bb_execvp(const char *file, char *const argv[]) FAST_FUNC;
-#define BB_EXECVP(prog,cmd) bb_execvp(prog,cmd)
+int BB_EXECVP(const char *file, char *const argv[]) FAST_FUNC;
 #define BB_EXECLP(prog,cmd,...) \
-        execlp((find_applet_by_name(prog) >= 0) ? CONFIG_BUSYBOX_EXEC_PATH : prog, \
-                cmd, __VA_ARGS__)
+        do { \
+                if (find_applet_by_name(prog) >= 0) \
+                        execlp(bb_busybox_exec_path, cmd, __VA_ARGS__); \
+                execlp(prog, cmd, __VA_ARGS__); \
+        } while (0)
 #else
 #define BB_EXECVP(prog,cmd)     execvp(prog,cmd)
-#define BB_EXECLP(prog,cmd,...) execlp(prog,cmd, __VA_ARGS__)
+#define BB_EXECLP(prog,cmd,...) execlp(prog,cmd,__VA_ARGS__)
 #endif
 int BB_EXECVP_or_die(char **argv) NORETURN FAST_FUNC;
 
diff --git a/libbb/execable.c b/libbb/execable.c
index d37640007..178a00a5f 100644
--- a/libbb/execable.c
+++ b/libbb/execable.c
@@ -68,12 +68,12 @@ int FAST_FUNC exists_execable(const char *filename)
 }
 
 #if ENABLE_FEATURE_PREFER_APPLETS
-/* just like the real execvp, but try to launch an applet named 'file' first
- */
-int FAST_FUNC bb_execvp(const char *file, char *const argv[])
+/* just like the real execvp, but try to launch an applet named 'file' first */
+int FAST_FUNC BB_EXECVP(const char *file, char *const argv[])
 {
-        return execvp(find_applet_by_name(file) >= 0 ? bb_busybox_exec_path : file,
-                                        argv);
+        if (find_applet_by_name(file) >= 0)
+                execvp(bb_busybox_exec_path, argv);
+        return execvp(file, argv);
 }
 #endif
 
diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c
index 5e0fb0d73..cb4781a59 100644
--- a/libbb/vfork_daemon_rexec.c
+++ b/libbb/vfork_daemon_rexec.c
@@ -182,17 +182,17 @@ int FAST_FUNC spawn_and_wait(char **argv)
         int a = find_applet_by_name(argv[0]);
 
         if (a >= 0 && (APPLET_IS_NOFORK(a)
-#if BB_MMU
+# if BB_MMU
                         || APPLET_IS_NOEXEC(a) /* NOEXEC trick needs fork() */
-#endif
+# endif
         )) {
-#if BB_MMU
+# if BB_MMU
                 if (APPLET_IS_NOFORK(a))
-#endif
+# endif
                 {
                         return run_nofork_applet(a, argv);
                 }
-#if BB_MMU
+# if BB_MMU
                 /* MMU only */
                 /* a->noexec is true */
                 rc = fork();
@@ -201,7 +201,7 @@ int FAST_FUNC spawn_and_wait(char **argv)
                 /* child */
                 xfunc_error_retval = EXIT_FAILURE;
                 run_applet_no_and_exit(a, argv);
-#endif
+# endif
         }
 #endif /* FEATURE_PREFER_APPLETS */
         rc = spawn(argv);