2008-09-05 22:52:23

by Chuck Lever III

[permalink] [raw]
Subject: [PATCH] NFS: Restore missing hunk in NFS mount option parser

Automounter maps can contain mount options valid for other NFS
implementations but not for Linux. The Linux automounter uses the
mount command's "-s" command line option ("s" for "sloppy") so that
mount requests containing such options are not rejected.

Commit f45663ce5fb30f76a3414ab3ac69f4dd320e760a attempted to address a
known regression with text-based NFS mount option parsing. Unrecognized
mount options would cause mount requests to fail, even if the "-s"
option was used on the mount command line.

Unfortunately, this commit was not complete as submitted. The commit
adds a new mount option, "sloppy". But it is missing a hunk, so it now
allows NFS mounts with unrecognized mount options, even if the "sloppy"
option is not present. This could be a problem if a required critical
mount option such as "sync" is misspelled, for example, and is considered
a regression from 2.6.26.

This patch restores the missing hunk. Now, the default behavior of
text-based NFS mount options is as before: any unrecognized mount option
will cause the mount to fail.

Please include this in 2.6.27-rc.

Thanks to Neil Brown for spotting this.

Signed-off-by: Chuck Lever <[email protected]>

fs/nfs/super.c | 6 ++++++
1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 5b2aa04..e3ac650 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -1279,6 +1279,12 @@ static int nfs_parse_mount_options(char *raw,

+ if (errors > 0) {
+ dfprintk(MOUNT, "NFS: parsing encountered %d error%s\n",
+ errors, (errors == 1 ? "" : "s"));
+ if (!sloppy)
+ return 0;
+ }
return 1;