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 CADC9308F00; Mon, 3 Nov 2025 11:27:27 +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=1762169247; cv=none; b=aM80Oj38KT1xe61dHYav1xs4MKrJ95XlFjwJ68Gu328J+wbDF9T7fw5MkO4HejkzqZC6qdZTAjO5uc/hSvWZnwX16VUf6BN5jknd+WXPRucGbZ4Uo9Ckhm3+YOa9P5sqbhAZFa4SjUJRuMyfhmwpN36GrM+jpJgRDfcfxcEQXqo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762169247; c=relaxed/simple; bh=xUgfCnEjAJd8zsIOSMA0urqHXlAuN0jLc7ICsbqbewI=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=XiF8df5ilFM8sOYKFNeGQnknhbBga6Hq8zbNzol8oKIaD3uGk7Ypsn3AGiy1T8r4MmmTarPOjhOhpHAk/cH3WJRZQim9qPmbtr1hCX4uc891xjm51UEEtsJzJb5isMtjy6Sryu768PuEQMzz1m2t6h2APDELlvMkHlZ23x0LdRU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=t/7pepPe; 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="t/7pepPe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 47F83C4CEF8; Mon, 3 Nov 2025 11:27:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1762169247; bh=xUgfCnEjAJd8zsIOSMA0urqHXlAuN0jLc7ICsbqbewI=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=t/7pepPe+E2EpzUMqDzgHBspZi4YmYJq/8kyKPd8F4ea0WwzTWUKxbhr9BQn21g5p 4vUpHCHemXB6WCn+RWve8MTpNaOMgVq+V0G5Yt9dQGt0TYSSpSuF+1vBLHm6cV79V4 /Ef3Br+/I9RsZpUSXomjNPfGTamKACdaOSk0aWyoYYbif609YCwiJSx2Jh98aQ0Ofq CUodanmAKxk14DxR2ZdZsqfrSW1kzhfNI30558rjyOaZaOOTPVDEixp7GSLHnmdi6W X5H+Gu6tSKRCbmMwJz3DH/sLJXc1koIR94pNFloTG1GIny0GDGT2y0+626ZCaEyXMX Gic7qzrFm9jUA== From: Christian Brauner Date: Mon, 03 Nov 2025 12:26:55 +0100 Subject: [PATCH 07/16] backing-file: use credential guards for mmap Precedence: bulk X-Mailing-List: linux-cifs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20251103-work-creds-guards-simple-v1-7-a3e156839e7f@kernel.org> References: <20251103-work-creds-guards-simple-v1-0-a3e156839e7f@kernel.org> In-Reply-To: <20251103-work-creds-guards-simple-v1-0-a3e156839e7f@kernel.org> To: Linus Torvalds Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-aio@kvack.org, linux-unionfs@vger.kernel.org, linux-erofs@lists.ozlabs.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, cgroups@vger.kernel.org, netdev@vger.kernel.org, Christian Brauner X-Mailer: b4 0.15-dev-96507 X-Developer-Signature: v=1; a=openpgp-sha256; l=1027; i=brauner@kernel.org; h=from:subject:message-id; bh=xUgfCnEjAJd8zsIOSMA0urqHXlAuN0jLc7ICsbqbewI=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWRyTGx/tYdp5/3NnxKWxT267pvpVHLYZbnKu5ednnuOs ptrr97xpaOUhUGMi0FWTJHFod0kXG45T8Vmo0wNmDmsTCBDGLg4BWAiB3oYGf7bPVoYHBDtkvTm j0NBZrlhXOds+5m3OFIvVuu+nu7zMJ6RYXlZ6M8HAc6f/y7vskkP+syb1GXX780bzNOpyb/ifMp edgA= X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Use credential guards for scoped credential override with automatic restoration on scope exit. Signed-off-by: Christian Brauner --- fs/backing-file.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/fs/backing-file.c b/fs/backing-file.c index 9c63a3368b66..5cc4b59aa460 100644 --- a/fs/backing-file.c +++ b/fs/backing-file.c @@ -331,7 +331,6 @@ EXPORT_SYMBOL_GPL(backing_file_splice_write); int backing_file_mmap(struct file *file, struct vm_area_struct *vma, struct backing_file_ctx *ctx) { - const struct cred *old_cred; struct file *user_file = vma->vm_file; int ret; @@ -343,9 +342,8 @@ int backing_file_mmap(struct file *file, struct vm_area_struct *vma, vma_set_file(vma, file); - old_cred = override_creds(ctx->cred); - ret = vfs_mmap(vma->vm_file, vma); - revert_creds(old_cred); + scoped_with_creds(ctx->cred) + ret = vfs_mmap(vma->vm_file, vma); if (ctx->accessed) ctx->accessed(user_file); -- 2.47.3