init: do not use bb_sanitize_stdio(), "/dev/null" may be missing (yet)

1 files changed, 16 insertions, 2 deletions

diff --git a/init/init.c b/init/init.c
index 6d4969c..eefb9df 100644
--- a/init/init.c
+++ b/init/init.c
@@ -219,8 +219,22 @@ static void console_init(void)
 		}
 		messageD(L_LOG, "console='%s'", s);
 	} else {
-		/* Make sure fd 0,1,2 are not closed */
-		bb_sanitize_stdio();
+		/* Make sure fd 0,1,2 are not closed
+		 * (so that they won't be used by future opens) */
+
+		/* bb_sanitize_stdio(); - WRONG.
+		 * Fail if "/dev/null" doesnt exist, and for init
+		 * this is a real possibility! Open code it instead. */
+
+		int fd = open(bb_dev_null, O_RDWR);
+		if (fd < 0) {
+			/* Give me _ANY_ open descriptor! */
+			fd = xopen("/", O_RDONLY); /* we don't believe this can fail */
+		}
+    		while ((unsigned)fd < 2)
+            		fd = dup(fd);
+		if (fd > 2)
+			close (fd);
 	}
 
 	s = getenv("TERM");