From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C54D23991AF; Mon, 5 May 2025 23:07:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746486470; cv=none; b=U8XMeBD/RHnL7fgz2Ltjv+4BPtUjewgzS/kJiUBUuSGxTSBYCI4fiaPwn6/qK17wsHTpW97OXcNlvf4g7l1L8EFWa3025qTK46i1X7AXEkpNjT041v74CVaWZOt/I/8geefAVXWQTucrIwxNTqxspr7lWp2rdGrZXfKwH2W9i0I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746486470; c=relaxed/simple; bh=Kla4zjxFzkrE6Pr2b/gaHFQSldCKjlm/rmVI/KRUkA8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=NaI0GxXntE9pKDWCeGr6TkSjMeaEB23QfoQggNJXO2RxDMH1p8INiX4fzdOFdLOfXymAAsfXPpHY9L9hGIObLZGOhHgOgN/m/6HzkgS8flHHtIOBh5npi1rtFH7Hb7QbMm2TkJ+p7x4qvk8m6vID3ndq/vLI8bZA9HEwSWaSlHw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WlPdMvJe; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="WlPdMvJe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 99F56C4CEF1; Mon, 5 May 2025 23:07:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746486469; bh=Kla4zjxFzkrE6Pr2b/gaHFQSldCKjlm/rmVI/KRUkA8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WlPdMvJeBMiTkPdp7TXxruBxCKvA1lA/ND9QHe0tz5N/wBbB337YQeO64HAsprpvy 9x9dQAVIBiYMdXLrF9y/gOjvzi29WRntDdN3EviQDK+kbCu61ra3RQCbJ0FHWWyxuY YIrMwWmLGV3p0W50Z0XJt4Cj0KCqDIth46kyEgQAzUJHSGYtGzvOpjnPI/hYVngAsc Y3P/2UhvHOmnQQYx/m5nix8mqSKy7lxuhnb/1/4v/QikJK5HwI4IJtrRlF4HWWx2bD Qa1ebv0ZNma8ukDjPNG50R5c3KpQAgiN/yj1UOa/v0BlcEwu3/+m8s5S2sE0IyfpBd vv6d0SKZTS/dA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: =?UTF-8?q?Christian=20G=C3=B6ttsche?= , Serge Hallyn , Jan Kara , Theodore Ts'o , Sasha Levin , adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org Subject: [PATCH AUTOSEL 6.1 046/212] ext4: reorder capability check last Date: Mon, 5 May 2025 19:03:38 -0400 Message-Id: <20250505230624.2692522-46-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250505230624.2692522-1-sashal@kernel.org> References: <20250505230624.2692522-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.1.136 Content-Transfer-Encoding: 8bit From: Christian Göttsche [ Upstream commit 1b419c889c0767a5b66d0a6c566cae491f1cb0f7 ] capable() calls refer to enabled LSMs whether to permit or deny the request. This is relevant in connection with SELinux, where a capability check results in a policy decision and by default a denial message on insufficient permission is issued. It can lead to three undesired cases: 1. A denial message is generated, even in case the operation was an unprivileged one and thus the syscall succeeded, creating noise. 2. To avoid the noise from 1. the policy writer adds a rule to ignore those denial messages, hiding future syscalls, where the task performs an actual privileged operation, leading to hidden limited functionality of that task. 3. To avoid the noise from 1. the policy writer adds a rule to permit the task the requested capability, while it does not need it, violating the principle of least privilege. Signed-off-by: Christian Göttsche Reviewed-by: Serge Hallyn Reviewed-by: Jan Kara Link: https://patch.msgid.link/20250302160657.127253-2-cgoettsche@seltendoof.de Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin --- fs/ext4/balloc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index fbd0329cf254e..9efe97f3721bc 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -638,8 +638,8 @@ static int ext4_has_free_clusters(struct ext4_sb_info *sbi, /* Hm, nope. Are (enough) root reserved clusters available? */ if (uid_eq(sbi->s_resuid, current_fsuid()) || (!gid_eq(sbi->s_resgid, GLOBAL_ROOT_GID) && in_group_p(sbi->s_resgid)) || - capable(CAP_SYS_RESOURCE) || - (flags & EXT4_MB_USE_ROOT_BLOCKS)) { + (flags & EXT4_MB_USE_ROOT_BLOCKS) || + capable(CAP_SYS_RESOURCE)) { if (free_clusters >= (nclusters + dirty_clusters + resv_clusters)) -- 2.39.5