From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Eric Snowberg <eric.snowberg@oracle.com>,
Mimi Zohar <zohar@linux.ibm.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Sasha Levin <sashal@kernel.org>,
miklos@szeredi.hu, amir73il@gmail.com,
linux-unionfs@vger.kernel.org
Subject: [PATCH AUTOSEL 5.15 26/31] ovl: Always reevaluate the file signature for IMA
Date: Sun, 13 Aug 2023 12:05:59 -0400 [thread overview]
Message-ID: <20230813160605.1080385-26-sashal@kernel.org> (raw)
In-Reply-To: <20230813160605.1080385-1-sashal@kernel.org>
From: Eric Snowberg <eric.snowberg@oracle.com>
[ Upstream commit 18b44bc5a67275641fb26f2c54ba7eef80ac5950 ]
Commit db1d1e8b9867 ("IMA: use vfs_getattr_nosec to get the i_version")
partially closed an IMA integrity issue when directly modifying a file
on the lower filesystem. If the overlay file is first opened by a user
and later the lower backing file is modified by root, but the extended
attribute is NOT updated, the signature validation succeeds with the old
original signature.
Update the super_block s_iflags to SB_I_IMA_UNVERIFIABLE_SIGNATURE to
force signature reevaluation on every file access until a fine grained
solution can be found.
Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/overlayfs/super.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 5310271cf2e38..e18025b5c8872 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -2140,7 +2140,7 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
ovl_trusted_xattr_handlers;
sb->s_fs_info = ofs;
sb->s_flags |= SB_POSIXACL;
- sb->s_iflags |= SB_I_SKIP_SYNC;
+ sb->s_iflags |= SB_I_SKIP_SYNC | SB_I_IMA_UNVERIFIABLE_SIGNATURE;
err = -ENOMEM;
root_dentry = ovl_get_root(sb, upperpath.dentry, oe);
--
2.40.1
parent reply other threads:[~2023-08-13 16:11 UTC|newest]
Thread overview: expand[flat|nested] mbox.gz Atom feed
[parent not found: <20230813160605.1080385-1-sashal@kernel.org>]
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=20230813160605.1080385-26-sashal@kernel.org \
--to=sashal@kernel.org \
--cc=amir73il@gmail.com \
--cc=eric.snowberg@oracle.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-unionfs@vger.kernel.org \
--cc=miklos@szeredi.hu \
--cc=stable@vger.kernel.org \
--cc=torvalds@linux-foundation.org \
--cc=zohar@linux.ibm.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
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).