linux-unionfs mirror
 help / color / mirror / Atom feed
From: David Disseldorp <ddiss@suse.de>
To: selinux@vger.kernel.org
Cc: linux-unionfs@vger.kernel.org, David Disseldorp <ddiss@suse.de>
Subject: [PATCH] RFC: selinux: don't filter copy-up xattrs while uninitialized
Date: Wed, 18 Oct 2023 12:08:15 +0200	[thread overview]
Message-ID: <20231018100815.26278-1-ddiss@suse.de> (raw)

Extended attribute copy-up functionality added via 19472b69d639d
("selinux: Implementation for inode_copy_up_xattr() hook") sees
"security.selinux" contexts dropped, instead relying on contexts
applied via the inode_copy_up() hook.

When copy-up takes place during early boot, prior to selinux
initialization / policy load, the context stripping can be unwanted
and unexpected. Make filtering dependent on selinux_initialized().

RFC: This changes user behaviour so is likely unacceptable. Still,
I'd be interested in hearing other suggestions for how this could be
addressed.
---
 security/selinux/hooks.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 2aa0e219d7217..fb3e53bb7e90c 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3527,7 +3527,7 @@ static int selinux_inode_copy_up_xattr(const char *name)
 	 * don't then want to overwrite it by blindly copying all the lower
 	 * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
 	 */
-	if (strcmp(name, XATTR_NAME_SELINUX) == 0)
+	if (selinux_initialized() && strcmp(name, XATTR_NAME_SELINUX) == 0)
 		return 1; /* Discard */
 	/*
 	 * Any other attribute apart from SELINUX is not claimed, supported
-- 
2.35.3


             reply	other threads:[~2023-10-18 10:08 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-10-18 10:08 David Disseldorp [this message]
2023-10-20 12:21 ` [PATCH] RFC: selinux: don't filter copy-up xattrs while uninitialized Stephen Smalley
2023-10-20 15:55   ` Paul Moore
2023-10-20 20:33     ` David Disseldorp
2023-11-20 23:03       ` Paul Moore

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=20231018100815.26278-1-ddiss@suse.de \
    --to=ddiss@suse.de \
    --cc=linux-unionfs@vger.kernel.org \
    --cc=selinux@vger.kernel.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 read-only IMAP folder(s) and NNTP newsgroup(s).