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
next prev 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
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