Linux-Fsdevel Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Max Kellermann <mk@cm4all.com>
To: linux-fsdevel@vger.kernel.org, hch@infradead.org,
	linux-nfs@vger.kernel.org, trond.myklebust@primarydata.com,
	gregkh@linuxfoundation.org
Cc: max.kellermann@gmail.com, linux-kernel@vger.kernel.org
Subject: [PATCH 2/2] dFrom: Max Kellermann <mk@cm4all.com>
Date: Mon, 15 Jan 2018 18:30:51 +0100	[thread overview]
Message-ID: <151603745169.29035.6866708909114015882.stgit@rabbit.intern.cm-ag> (raw)
In-Reply-To: <151603744662.29035.4910161264124875658.stgit@rabbit.intern.cm-ag>

nfs/super: set MS_POSIXACL only if ACL support is enabled

The code comment says "We will [apply the umask] ourselves", but that
happens in posix_acl_create() only if the kernel has POSIX ACL
support.  Without it, posix_acl_create() is a is an empty dummy
function.

So let's not pretend we will apply the umask if we can already know
that we will never.

This fixes a problem where the umask is always ignored in the NFS
client when compiled without CONFIG_FS_POSIX_ACL.  This is a 4 year
old regression caused by commit 013cdf1088d723 which itself was not
completely wrong, but failed to consider all the side effects by
misdesigned VFS code.

There are two compile-time checks and one runtime check:

- If CONFIG_FS_POSIX_ACL=n, then MS_POSIXACL is never set.

- If CONFIG_FS_POSIX_ACL=y and CONFIG_NFS_V3_ACL=n, then only NFSv4
  has ACL support (and cannot be disabled), and we need to check for
  "version==4".

- If CONFIG_FS_POSIX_ACL=y and CONFIG_NFS_V3_ACL=y, MS_POSIXACL is
  always set, as before.

Signed-off-by: Max Kellermann <mk@cm4all.com>
---
 fs/nfs/super.c |   15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 216f67d628b3..ec4e1f2775e0 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -2338,10 +2338,17 @@ void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
 		sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
 
 	if (server->nfs_client->rpc_ops->version != 2) {
-		/* The VFS shouldn't apply the umask to mode bits. We will do
-		 * so ourselves when necessary.
-		 */
-		sb->s_flags |= MS_POSIXACL;
+#ifdef CONFIG_FS_POSIX_ACL
+#ifndef CONFIG_NFS_V3_ACL
+		if (nfss->nfs_client->rpc_ops->version == 4)
+#endif
+			/* The VFS shouldn't apply the umask to mode
+			 * bits. We will do so ourselves when
+			 * necessary.
+			 */
+			sb->s_flags |= MS_POSIXACL;
+#endif
+
 		sb->s_time_gran = 1;
 		sb->s_export_op = &nfs_export_ops;
 	}

  reply	other threads:[~2018-01-15 17:39 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-01-15 17:30 [PATCH 1/2] linux/fs.h: fix umask on NFS with CONFIG_FS_POSIX_ACL=n Max Kellermann
2018-01-15 17:30 ` Max Kellermann [this message]
2018-01-15 17:41   ` [PATCH 2/2] dFrom: Max Kellermann <mk@cm4all.com> Greg KH
2018-01-15 17:43     ` Max Kellermann
2018-01-16 15:06   ` Trond Myklebust
2018-01-17 16:37 ` [PATCH 1/2] linux/fs.h: fix umask on NFS with CONFIG_FS_POSIX_ACL=n J. Bruce Fields

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=151603745169.29035.6866708909114015882.stgit@rabbit.intern.cm-ag \
    --to=mk@cm4all.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=hch@infradead.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-nfs@vger.kernel.org \
    --cc=max.kellermann@gmail.com \
    --cc=trond.myklebust@primarydata.com \
    --subject='Re: [PATCH 2/2] dFrom: Max Kellermann <mk@cm4all.com>' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).