From: Theodore Ts'o <tytso@mit.edu>
Date: Mon, 29 Jun 2009 23:06:45 +0000 (-0400)
Subject: libuuid: Make sure fd's 0, 1, and 2 are valid before exec'ing uuidd
X-Git-Tag: v1.41.8~31
X-Git-Url: https://git.whamcloud.com/?a=commitdiff_plain;h=e8b9466fc9d4aec66476f1bc7a48436da02ab557;p=tools%2Fe2fsprogs.git

libuuid: Make sure fd's 0, 1, and 2 are valid before exec'ing uuidd

When closing all of the file descriptors before starting uuidd, make
sure file descriptors 0, 1, and 2 are reserved by opening /dev/null.
This prevents strange bugs caused by assumptions regarding file
descriptors <= 2 as being special.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
---

diff --git a/lib/uuid/gen_uuid.c b/lib/uuid/gen_uuid.c
index b7a12ee..aa313ef 100644
--- a/lib/uuid/gen_uuid.c
+++ b/lib/uuid/gen_uuid.c
@@ -455,8 +455,11 @@ static void close_all_fds(void)
 	max = OPEN_MAX;
 #endif
 
-	for (i=0; i < max; i++)
+	for (i=0; i < max; i++) {
 		close(i);
+		if (i <= 2)
+			open("/dev/null", O_RDWR);
+	}
 }