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 C1268FC08 for ; Mon, 15 May 2023 17:40:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 270E2C4339B; Mon, 15 May 2023 17:40:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1684172408; bh=XTjihFU6sfVE3DukRlrR1IIuLac1INxglTQfGb+cx0Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pLSIAWm/MxTDrbkgffIiTadO54ak95IbUN94ZqS6V/g5BO/UQkwZhm+sbtDoYAszn KvW65E65kk/StOKY5acEh4cy2jvPkTm+Eqsio0wC73q9juF7XxhQ0tRU8/omrC4ZRd Roo2awJ3pCENBCmGVTdM2ywunsMa8iQkGqIRB9Ws= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , "David S. Miller" , Sasha Levin Subject: [PATCH 5.10 144/381] net/packet: convert po->auxdata to an atomic flag Date: Mon, 15 May 2023 18:26:35 +0200 Message-Id: <20230515161743.360399548@linuxfoundation.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230515161736.775969473@linuxfoundation.org> References: <20230515161736.775969473@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Eric Dumazet [ Upstream commit fd53c297aa7b077ae98a3d3d2d3aa278a1686ba6 ] po->auxdata can be read while another thread is changing its value, potentially raising KCSAN splat. Convert it to PACKET_SOCK_AUXDATA flag. Fixes: 8dc419447415 ("[PACKET]: Add optional checksum computation for recvmsg") Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/packet/af_packet.c | 8 +++----- net/packet/diag.c | 2 +- net/packet/internal.h | 4 ++-- 3 files changed, 6 insertions(+), 8 deletions(-) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index df93f4b09ab9e..9b6f6a5e0b147 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -3485,7 +3485,7 @@ static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa, copy_len); } - if (pkt_sk(sk)->auxdata) { + if (packet_sock_flag(pkt_sk(sk), PACKET_SOCK_AUXDATA)) { struct tpacket_auxdata aux; aux.tp_status = TP_STATUS_USER; @@ -3869,9 +3869,7 @@ packet_setsockopt(struct socket *sock, int level, int optname, sockptr_t optval, if (copy_from_sockptr(&val, optval, sizeof(val))) return -EFAULT; - lock_sock(sk); - po->auxdata = !!val; - release_sock(sk); + packet_sock_flag_set(po, PACKET_SOCK_AUXDATA, val); return 0; } case PACKET_ORIGDEV: @@ -4032,7 +4030,7 @@ static int packet_getsockopt(struct socket *sock, int level, int optname, break; case PACKET_AUXDATA: - val = po->auxdata; + val = packet_sock_flag(po, PACKET_SOCK_AUXDATA); break; case PACKET_ORIGDEV: val = packet_sock_flag(po, PACKET_SOCK_ORIGDEV); diff --git a/net/packet/diag.c b/net/packet/diag.c index e1ac9bb375b31..d704c7bf51b20 100644 --- a/net/packet/diag.c +++ b/net/packet/diag.c @@ -23,7 +23,7 @@ static int pdiag_put_info(const struct packet_sock *po, struct sk_buff *nlskb) pinfo.pdi_flags = 0; if (po->running) pinfo.pdi_flags |= PDI_RUNNING; - if (po->auxdata) + if (packet_sock_flag(po, PACKET_SOCK_AUXDATA)) pinfo.pdi_flags |= PDI_AUXDATA; if (packet_sock_flag(po, PACKET_SOCK_ORIGDEV)) pinfo.pdi_flags |= PDI_ORIGDEV; diff --git a/net/packet/internal.h b/net/packet/internal.h index 7fea453dc7215..3938cb413d5d3 100644 --- a/net/packet/internal.h +++ b/net/packet/internal.h @@ -118,8 +118,7 @@ struct packet_sock { struct mutex pg_vec_lock; unsigned long flags; unsigned int running; /* bind_lock must be held */ - unsigned int auxdata:1, /* writer must hold sock lock */ - has_vnet_hdr:1, + unsigned int has_vnet_hdr:1, /* writer must hold sock lock */ tp_loss:1, tp_tx_has_off:1; int pressure; @@ -146,6 +145,7 @@ static struct packet_sock *pkt_sk(struct sock *sk) enum packet_sock_flags { PACKET_SOCK_ORIGDEV, + PACKET_SOCK_AUXDATA, }; static inline void packet_sock_flag_set(struct packet_sock *po, -- 2.39.2