From a2a4dc494a7b7135f460e38e788c4a58f65e4ac3 Mon Sep 17 00:00:00 2001 From: Thomas Bächler Date: Thu, 3 Apr 2014 21:55:37 +0200 Subject: fs: Don't return 0 from get_anon_bdev MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 9e30cc9595303b27b48 removed an internal mount. This has the side-effect that rootfs now has FSID 0. Many userspace utilities assume that st_dev in struct stat is never 0, so this change breaks a number of tools in early userspace. Since we don't know how many userspace programs are affected, make sure that FSID is at least 1. References: http://article.gmane.org/gmane.linux.kernel/1666905 References: http://permalink.gmane.org/gmane.linux.utilities.util-linux-ng/8557 Cc: 3.14 Signed-off-by: Thomas Bächler Acked-by: Tejun Heo Acked-by: H. Peter Anvin Tested-by: Alexandre Demers Signed-off-by: Greg Kroah-Hartman --- fs/super.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'fs/super.c') diff --git a/fs/super.c b/fs/super.c index e9dc3c3fe159..48377f7463c0 100644 --- a/fs/super.c +++ b/fs/super.c @@ -800,7 +800,10 @@ void emergency_remount(void) static DEFINE_IDA(unnamed_dev_ida); static DEFINE_SPINLOCK(unnamed_dev_lock);/* protects the above */ -static int unnamed_dev_start = 0; /* don't bother trying below it */ +/* Many userspace utilities consider an FSID of 0 invalid. + * Always return at least 1 from get_anon_bdev. + */ +static int unnamed_dev_start = 1; int get_anon_bdev(dev_t *p) { -- cgit