| From | Greg Kroah-Hartman <> | Subject | [PATCH 3.18 50/52] Dont leak MNT_INTERNAL away from internal mounts | Date | Sun, 22 Apr 2018 15:54:23 +0200 |
| |
3.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Al Viro <viro@zeniv.linux.org.uk>
commit 16a34adb9392b2fe4195267475ab5b472e55292c upstream.
We want it only for the stuff created by SB_KERNMOUNT mounts, *not* for their copies. As it is, creating a deep stack of bindings of /proc/*/ns/* somewhere in a new namespace and exiting yields a stack overflow.
Cc: stable@kernel.org Reported-by: Alexander Aring <aring@mojatatu.com> Bisected-by: Kirill Tkhai <ktkhai@virtuozzo.com> Tested-by: Kirill Tkhai <ktkhai@virtuozzo.com> Tested-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- fs/namespace.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/fs/namespace.c +++ b/fs/namespace.c @@ -944,7 +944,8 @@ static struct mount *clone_mnt(struct mo goto out_free; } - mnt->mnt.mnt_flags = old->mnt.mnt_flags & ~(MNT_WRITE_HOLD|MNT_MARKED); + mnt->mnt.mnt_flags = old->mnt.mnt_flags; + mnt->mnt.mnt_flags &= ~(MNT_WRITE_HOLD|MNT_MARKED|MNT_INTERNAL); /* Don't allow unprivileged users to change mount flags */ if (flag & CL_UNPRIVILEGED) { mnt->mnt.mnt_flags |= MNT_LOCK_ATIME;
|