From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793633552; b=qwgJf24anSene9dGMw77bj2C8fTTHDmWDc0M5THxexdfMdzR2z/xcPVLIwkk5DLlQLWU sZO6Kxyb1GlohfogERLw8oRLUdKvqps9OdMx4t1FkyPeY0pvnCZxi30FoXiztvg3CVqJ2 eVpBGBTkwd1QOJL/FjS92RxqGO87SPr0PDjhm3R//Kr5Y+UYProm5liDmvh6V2vVogTyn xv6HTQKgukotp/zmiTvm1lxxCNZ4gisBdlECYtkranrX+Ko4lu0PEeEGkNx6GAusq9X8P EesOghqrUJ2n5MbMwA3mXsfEI322GT4s7WkGiLJsr4jnEwu5yAr+m6ma0hlZfWYoxQw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793633552; h=Received:DKIM-Signature:From:Date:Subject:MIME-Version:Content-Type: Content-Transfer-Encoding:Message-Id:References:In-Reply-To:To:Cc: X-Mailer:X-Developer-Signature:X-Developer-Key; bh=j0XEj0YD19hajZrTiSL4Hx5oTZ822IFleoT2hqE8QNQ=; b=XqtCNrQiUi9hDYY18MdMXLACC6nO/CTXDr70qJwGT9+5N9yJk+kZ9Tkmm+9QzgATxsw8 2AW3/yF/Cqo83/OfIiY4TzJwTIFCv/UyZCCySfbFlclB/OvFMom6bUoYdlNmXUkGuH6xA qAqsU/F5PD5hk0T/uEpuqr6CM/Q67tlddcR0g45k+mhb8vd7oo5ZWqPoyAjAqW0hwoHst Mu7pYsP/TO+Lexy8huGI3ivO0UDNpUZqrebr2juBludWLl6zh49rGTrOkcy3q/OEsCzNR MV8L5lc1dVX4CIDKKlqQPf5g7IjzL3nHf2omZhbXZgeCLXNJuoPDqtsqtZN9TNcY6jQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=WOtNUR7A; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1322C6072283; Mon, 2 Nov 2026 15:32:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=WOtNUR7A Received: by smtp.kernel.org (Postfix) with ESMTPSA id 714811F00A1A; Mon, 2 Nov 2026 15:32:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793633551; bh=j0XEj0YD19hajZrTiSL4Hx5oTZ822IFleoT2hqE8QNQ=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=WOtNUR7ANTbV8Aq+NS5tB7HOgtUYtUFBrHUduOMXGSrvyvVh49FKtJAtPA79xEdKK bWLuxrK34vw5XvQe2Ses1fW882zwHJNi0DTpIw4mOgryVfyh06j3VgDnExsFIakuQ5 myUaZwuXJOiUD0AVpk0r2EDdW+XFBxyBcKxkzbyxcSh7mpU9vIC53YIaLvGKA95Tv5 l0wnd9SE3I99/RpnQwpcxyDZJh+XRZ7Gez9UyXhApoK8ws1dteMc6OckWGLtrOFM+7 gV/vEgFiiBUWN/JNUdIJHozxukOMKP9vkwq6miFhFVRTjftdm1zZuN9/BGNHxbp7GI sMgsvoriwacXQ== From: Christian Brauner Date: Mon, 02 Nov 2026 16:07:19 +0100 Subject: [PATCH RFC 05/11] netfilter: xt_recent: let procfs copy in writes X-Mailing-List: linux-modules@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20261102-work-procfs-net-v1-5-982104a4f592@kernel.org> References: <20261102-work-procfs-net-v1-0-982104a4f592@kernel.org> In-Reply-To: <20261102-work-procfs-net-v1-0-982104a4f592@kernel.org> To: linux-fsdevel@vger.kernel.org Cc: Linus Torvalds , Jann Horn , Josef Bacik , Chris Mason , Jeff Layton , NeilBrown , Eric Dumazet , Thomas Gleixner , Al Viro , Jonathan Corbet , Christoph Hellwig , Greg Kroah-Hartman , Joel Granados , Kees Cook , Jan Kara , Jan Kara , linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, linux-um@lists.infradead.org, linux-wireless@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, ntfs3@lists.linux.dev, platform-driver-x86@vger.kernel.org, coreteam@netfilter.org, kexec@lists.infradead.org, linux-pci@vger.kernel.org, linux-sound@vger.kernel.org, netfilter-devel@vger.kernel.org, dri-devel@lists.freedesktop.org, ibm-acpi-devel@lists.sourceforge.net, jfs-discussion@lists.sourceforge.net, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-cifs@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-mm@kvack.org, linux-sh@vger.kernel.org, linux-usb@vger.kernel.org, samba-technical@lists.samba.org, sparclinux@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-doc@vger.kernel.org, linux-serial@vger.kernel.org, linux-atm-general@lists.sourceforge.net, Takashi Iwai , linux-input@vger.kernel.org, linux-raid@vger.kernel.org, linux-ext4@vger.kernel.org, linux-modules@vger.kernel.org, linux-debuggers@vger.kernel.org, "Christian Brauner (Amutable)" , Chuck Lever X-Mailer: b4 0.17-dev X-Developer-Signature: v=1; a=openpgp-sha256; l=1724; i=brauner@kernel.org; h=from:subject:message-id; bh=m6dNErjBjmz9XKGa3rT6vumTNxSZMRjmxs3KBefnnQ8=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWS9WG7ccSQ+KU5P1WO9/aOk9EeM4vLnjsV0vNLouKtsy VSiVh/SUcrCIMbFICumyOLQbhIut5ynYrNRpgbMHFYmkCEMXJwCMBGms4wMX9eu8Tt9WbzpS8+D b9e3s2i/FAvXOGvYKGJYVuMb/Oy2IcM/vbLA/s/ikvwyn4PDDs4pne0p8eNi9MxKj7iwnmCdYhF uAA== X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Implement ->proc_write_buf() so procfs copies in what is written to /proc/net/xt_recent/ before it pins the entry, and take the address from that copy. The removal of a table runs under recent_mutex and doesn't wait for a writer that faults on its buffer anymore. Writes larger than PAGE_SIZE - 1 bytes fail with -EINVAL now. Signed-off-by: Christian Brauner (Amutable) --- net/netfilter/xt_recent.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c index b771cc463aab..306557f25daf 100644 --- a/net/netfilter/xt_recent.c +++ b/net/netfilter/xt_recent.c @@ -553,8 +553,7 @@ static int recent_seq_open(struct inode *inode, struct file *file) } static ssize_t -recent_mt_proc_write(struct file *file, const char __user *input, - size_t size, loff_t *loff) +recent_mt_proc_write(struct file *file, char *input, size_t size, loff_t *loff) { struct recent_table *t = pde_data(file_inode(file)); struct recent_entry *e; @@ -568,8 +567,7 @@ recent_mt_proc_write(struct file *file, const char __user *input, return 0; if (size > sizeof(buf)) size = sizeof(buf); - if (copy_from_user(buf, input, size) != 0) - return -EFAULT; + memcpy(buf, input, size); /* Strict protocol! */ if (*loff != 0) @@ -625,7 +623,7 @@ static const struct proc_ops recent_mt_proc_ops = { .proc_seq_ops = &recent_seq_ops, .proc_state_size = sizeof(struct recent_iter_state), .proc_open = recent_seq_open, - .proc_write = recent_mt_proc_write, + .proc_write_buf = recent_mt_proc_write, }; static int __net_init recent_proc_net_init(struct net *net) -- 2.53.0