From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 E095D41763 for ; Tue, 14 Nov 2023 15:33:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="mNQkRNmk" Received: from mail-wm1-x333.google.com (mail-wm1-x333.google.com [IPv6:2a00:1450:4864:20::333]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AEFF9182 for ; Tue, 14 Nov 2023 07:33:29 -0800 (PST) Received: by mail-wm1-x333.google.com with SMTP id 5b1f17b1804b1-40859c466efso44898125e9.3 for ; Tue, 14 Nov 2023 07:33:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1699976008; x=1700580808; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=+DJ80duKXbFNKp+jJOZcJpxIS0hpPvz6Pb+tJw0y7TM=; b=mNQkRNmk/xMEQvgfgbgnELXh8nVmxj8TEY2I29TxKpW7FmlCxlCx3rBHCcs1HkNnCE JAzF/3xRzqGvBnzPy4thYuwnhXhKiPtAGcO+oiav9vXdwmBaJ+wL3hIwnFfXlXTyM5m2 sAjPNd8nDB/jdhYYtTN6j1lvGLDxdgrYT3JDW78WNJUfS9vSl9crYgFjOoQgo6n8RH/9 pZ0AJyfStd+cW/jjTdoEvrecBk3IHw1b2tKC4Eycc3Fdz4mI8ShhILqg+Ryk/7pP6tPs F4+7l1txWiWXcgFmsMTH39lLvOXBFAvwIvQOGBccBmyDo+/Fz+K790UMH6+LB5mwmKGs j25w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1699976008; x=1700580808; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=+DJ80duKXbFNKp+jJOZcJpxIS0hpPvz6Pb+tJw0y7TM=; b=ILvFZktNDlSXBvBwKoUb0BcvIL3QOK/3Xl/fJNWrqvTv9wwf7mcM0BW1IuTCLTDr12 8IOa/azjoqWjmWTVxIXHviGLGq1N0fOTjlnICmmaX9a8XZQCP3MXchN3xrFACXKOL7I6 EGjKiF66VjX6AHydVtsYkwtoxMuQF9WqYfi9v2s6o9hFkSfL3pDssxMwjCNNtrZwQ0Tk a5NQ1pf3qIV/aHkrjvRWyt9hmPunP0IdVb/+fnJalaePNL7gIa2XWlrVt46GlQRdGLbW iGn7dEOvA/uqUGY9qTA6ILb+tWZ1NWpsy32DetYnK/q6NZzSUxLz1P/gkdweaZY6hgpd JmIg== X-Gm-Message-State: AOJu0Yy4MIaU/2quFIuLak/lKV/m2zzeSf38X78NRxuRUwleg6OW+BjA DBGjZsxOUpANkk8vi2w+Ti0= X-Google-Smtp-Source: AGHT+IGnCQ9gUvV0KlIS7BQUp+hp1I93W3QI3yzVuj/h1RwfbuvtwYGmL29wNKPOFd5L27LYR4DjOw== X-Received: by 2002:a05:600c:4e91:b0:40a:44ed:27f3 with SMTP id f17-20020a05600c4e9100b0040a44ed27f3mr8033392wmq.8.1699976008016; Tue, 14 Nov 2023 07:33:28 -0800 (PST) Received: from amir-ThinkPad-T480.lan ([5.29.249.86]) by smtp.gmail.com with ESMTPSA id o9-20020a5d58c9000000b0032d9caeab0fsm8146527wrf.77.2023.11.14.07.33.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 14 Nov 2023 07:33:27 -0800 (PST) From: Amir Goldstein To: Christian Brauner Cc: Al Viro , Jan Kara , Jens Axboe , Miklos Szeredi , David Howells , linux-fsdevel@vger.kernel.org Subject: [PATCH 02/15] splice: remove permission hook from do_splice_direct() Date: Tue, 14 Nov 2023 17:33:08 +0200 Message-Id: <20231114153321.1716028-3-amir73il@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231114153321.1716028-1-amir73il@gmail.com> References: <20231114153321.1716028-1-amir73il@gmail.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit All callers of do_splice_direct() have a call to rw_verify_area() for the entire range that is being copied, e.g. by vfs_copy_file_range() or do_sendfile() before calling do_splice_direct(). The rw_verify_area() check inside do_splice_direct() is redundant and is called after sb_start_write(), so it is not "start-write-safe". Remove this redundant check. This is needed for fanotify "pre content" events. Signed-off-by: Amir Goldstein --- fs/splice.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/fs/splice.c b/fs/splice.c index d983d375ff11..6e917db6f49a 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -1166,6 +1166,7 @@ static void direct_file_splice_eof(struct splice_desc *sd) * (splice in + splice out, as compared to just sendfile()). So this helper * can splice directly through a process-private pipe. * + * Callers already called rw_verify_area() on the entire range. */ long do_splice_direct(struct file *in, loff_t *ppos, struct file *out, loff_t *opos, size_t len, unsigned int flags) @@ -1187,10 +1188,6 @@ long do_splice_direct(struct file *in, loff_t *ppos, struct file *out, if (unlikely(out->f_flags & O_APPEND)) return -EINVAL; - ret = rw_verify_area(WRITE, out, opos, len); - if (unlikely(ret < 0)) - return ret; - ret = splice_direct_to_actor(in, &sd, direct_splice_actor); if (ret > 0) *ppos = sd.pos; -- 2.34.1