linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Al Viro <viro@zeniv.linux.org.uk>
To: Christian Brauner <brauner@kernel.org>
Cc: linux-fsdevel@vger.kernel.org,
	Linus Torvalds <torvalds@linux-foundation.org>
Subject: [PATCH 3/4] do_move_mount(): don't leak MNTNS_PROPAGATING on failures
Date: Thu, 8 May 2025 21:02:11 +0100	[thread overview]
Message-ID: <20250508200211.GF2023217@ZenIV> (raw)
In-Reply-To: <20250508195916.GC2023217@ZenIV>

as it is, a failed move_mount(2) from anon namespace breaks
all further propagation into that namespace, including normal
mounts in non-anon namespaces that would otherwise propagate
there.

Fixes: 064fe6e233e8 ("mount: handle mount propagation for detached mount trees")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/namespace.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/fs/namespace.c b/fs/namespace.c
index d8a344d0a80a..04a9bb9f31fa 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -3715,15 +3715,14 @@ static int do_move_mount(struct path *old_path,
 	if (err)
 		goto out;
 
-	if (is_anon_ns(ns))
-		ns->mntns_flags &= ~MNTNS_PROPAGATING;
-
 	/* if the mount is moved, it should no longer be expire
 	 * automatically */
 	list_del_init(&old->mnt_expire);
 	if (attached)
 		put_mountpoint(old_mp);
 out:
+	if (is_anon_ns(ns))
+		ns->mntns_flags &= ~MNTNS_PROPAGATING;
 	unlock_mount(mp);
 	if (!err) {
 		if (attached) {
-- 
2.39.5


  parent reply	other threads:[~2025-05-08 20:02 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-04-28  6:30 [RFC] move_mount(2): still breakage around new mount detection Al Viro
2025-04-28  7:03 ` Al Viro
2025-04-28  8:50   ` Christian Brauner
2025-04-28 18:53     ` Al Viro
2025-04-29  4:03       ` Al Viro
2025-04-29  5:10         ` Al Viro
2025-04-29  5:27           ` Al Viro
2025-04-29  8:21           ` Christian Brauner
2025-05-05  5:08           ` Al Viro
2025-05-05 14:20             ` Christian Brauner
2025-04-29  7:56         ` Christian Brauner
2025-04-29 12:27           ` Al Viro
2025-04-29  7:52       ` Christian Brauner
2025-05-08  5:56       ` more breakage there (was Re: [RFC] move_mount(2): still breakage around new mount detection) Al Viro
2025-05-08 19:59         ` Al Viro
2025-05-08 20:00           ` [PATCH 1/4] __legitimize_mnt(): check for MNT_SYNC_UMOUNT should be under mount_lock Al Viro
2025-05-09 11:02             ` Christian Brauner
2025-05-08 20:01           ` [PATCH 2/4] do_umount(): add missing barrier before refcount checks in sync case Al Viro
2025-05-09 11:02             ` Christian Brauner
2025-05-08 20:02           ` Al Viro [this message]
2025-05-08 20:03             ` reproducer for "do_move_mount(): don't leak MNTNS_PROPAGATING on failures" Al Viro
2025-05-09 11:02             ` [PATCH 3/4] do_move_mount(): don't leak MNTNS_PROPAGATING on failures Christian Brauner
2025-05-13 11:03             ` Lai, Yi
2025-05-13 12:08               ` Al Viro
2025-05-13 14:33                 ` Lai, Yi
2025-05-08 20:02           ` [PATCH 4/4] fix IS_MNT_PROPAGATING uses Al Viro
2025-05-08 20:04             ` reproducer for "fix IS_MNT_PROPAGATING uses" Al Viro
2025-05-09 11:01             ` [PATCH 4/4] fix IS_MNT_PROPAGATING uses Christian Brauner
2025-05-09 11:06         ` more breakage there (was Re: [RFC] move_mount(2): still breakage around new mount detection) Christian Brauner

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=20250508200211.GF2023217@ZenIV \
    --to=viro@zeniv.linux.org.uk \
    --cc=brauner@kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=torvalds@linux-foundation.org \
    /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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
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).