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=1792696191; b=Tl8J83YIo+c3GhjO0Y+dN+uNyXMWn5sDmag5hxfOZj1qaEZ9EC3EgiZ9QCSBpzawj61H KcM5GpgVHaos7HCAdor8MPf4RsoMrHdSfEJ8Pbnyk6YTvJwYsSq34TucQ6OjNBD1rmxO+ mCrenFKwIKzdbIJ+onHMylP3w7n/Nh8CMjas9rsraOzLAXlrhqZQ0rhs2xoXvsZip9pbh CXnCmA6x4Jv3a4oDe6H+GmXIZWbaf3SbST2n4AFJPY0/9FPawmrzNDn8GhyltJ9cTd03V EBdM+PPcx2MpAT9e0qJe0fm4oD5CAjjxWz0XJGhWF286E+5s+EGmzkNQ33K+dobak/w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792696191; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=fCxZlEo0ucsHQqfC9SHZ/LmiNwn1AuS/FJ10XkVg6Bk=; b=WXj8L+nMq+/9HUkhvzbTRmq4nCU9alDMK2pSHJxxwxifzChq+Kpvzx+MBAIgBc59V5WM AcdeSCTMvVrufNL0W+DCKPO6/atOjIBo8j8+SapOYvnhOxEZkk9zrltJ/jrqGtSfuAmms Za3iXKC5InVjcF++dB3K0Id2ubKeEKpuerRYeJK0EymUfLmKKKW4/K/YQEmROnBUwXxko WohJJ72KBbr7W6iaz++1RrMH0SEKjFs5Sgylq/N54Yi5wZ4gYuDn4l0yMxRQacKtRa0I4 0wx7z1DcCCEb0Dd58EY0nUG1ZjcKNQpr9GOvJwcXCmQZCJ2/2ZPPFGPJJNkWhzikt8Q== 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=CpJjs9LQ; 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 3B671606A31A for ; Thu, 22 Oct 2026 19:09:50 +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=CpJjs9LQ Received: by smtp.kernel.org (Postfix) with ESMTPSA id C274F1F01828; Thu, 22 Oct 2026 19:09:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792696190; bh=fCxZlEo0ucsHQqfC9SHZ/LmiNwn1AuS/FJ10XkVg6Bk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=CpJjs9LQAEnEeV7cFO4vQLjr5KFi0LV4QChW5Iup5zQQRxowJb44dVTBQgu4jg6ED QFmz/FOxwqe91yw9UBzjPAYWmsUDn3Y/7Uw4jxjlo8dGdRHp1E2x19q8mYbQPrHbvx 1RGWZLf4sFlGltrRTpUDje18zKtcDg73NUU1T/qNYW80xHX6EKMAw6AJg6XO++kr/l 6ipmQBRXlbDb+CLGZOvrpxwD+l/omEoRgXPaZ61e92iibSkly4SaWgm3GVTyt065IL xXWeMXWHlrYPhvNOp1ce3NqM6opuwR6lIPEuwDnXdK5IPHry812rj7oRvJPSzGQSIC aUsMUc7wRzYkA== From: Sasha Levin To: stable@vger.kernel.org Cc: Daehyeon Ko <4ncienth@gmail.com>, Sashiko , Stefano Garzarella , Paolo Abeni , Vishnu Dasa , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.18.y] vsock/vmci: validate packet source for connected sockets Date: Thu, 22 Oct 2026 15:09:47 -0400 Message-ID: <20261022174744.1757572-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026102121-anymore-operable-f7bb@gregkh> References: <2026102121-anymore-operable-f7bb@gregkh> X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Daehyeon Ko <4ncienth@gmail.com> [ Upstream commit ad9a7da3fa39c2d616ec0dd3cf6e30531d032fe7 ] vmci_transport_recv_stream_cb() looks up sockets first by the full source and destination tuple, then by destination only in the bound table. The fallback can select a non-listening socket without checking whether the packet came from its stored peer. This was reproduced with two VMCI contexts. A RST from the context not stored in a TCP_SYN_SENT socket reset that socket after it was selected by the destination-only lookup. VMCI can process notification packets in bottom-half context when the socket is not owned by user context, or defer packets to a workqueue. Use vsock_check_source() after taking the socket lock in the bottom-half path, and recheck after lock_sock() in the workqueue path. Listening sockets continue to accept packets from any source. Reply with a RST addressed from the received packet before dropping a source that fails validation. This preserves the existing reset behavior for bound non-listening and concurrently closed sockets without directing the reset to a connected socket's stored peer. Fixes: d021c344051a ("VSOCK: Introduce VM Sockets") Reported-by: Sashiko Closes: https://lore.kernel.org/netdev/20260814121255.6B5001F000E9@smtp.kernel.org/ Cc: stable@vger.kernel.org Suggested-by: Stefano Garzarella Suggested-by: Paolo Abeni Signed-off-by: Daehyeon Ko <4ncienth@gmail.com> Reviewed-by: Vishnu Dasa Link: https://patch.msgid.link/20260826003929.966160-3-4ncienth@gmail.com Signed-off-by: Jakub Kicinski [ sashal: Replaced two calls to the unavailable vsock_check_source() helper with equivalent inline conditions. ] Signed-off-by: Sasha Levin --- Depends on <20261022162527.1685626-1-sashal@kernel.org> net/vmw_vsock/vmci_transport.c | 40 +++++++++++++++++++++++++++++----- 1 file changed, 34 insertions(+), 6 deletions(-) diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c index 4f02a6f269cdb..df0c472f9dd64 100644 --- a/net/vmw_vsock/vmci_transport.c +++ b/net/vmw_vsock/vmci_transport.c @@ -676,11 +676,13 @@ static int vmci_transport_recv_stream_cb(void *data, struct vmci_datagram *dg) struct vmci_transport_packet *pkt; struct vsock_sock *vsk; bool bh_process_pkt; + bool drop_pkt; int err; sk = NULL; err = VMCI_SUCCESS; bh_process_pkt = false; + drop_pkt = false; /* Ignore incoming packets from contexts without sockets, or resources * that aren't vsock implementations. @@ -757,17 +759,32 @@ static int vmci_transport_recv_stream_cb(void *data, struct vmci_datagram *dg) bh_lock_sock(sk); if (!sock_owned_by_user(sk)) { - /* The local context ID may be out of date, update it. */ - vsk->local_addr.svm_cid = dst.svm_cid; + if (sk->sk_state != TCP_LISTEN && + (vsk->transport != &vmci_transport || + src.svm_port != vsk->remote_addr.svm_port || + (src.svm_cid != vsk->remote_addr.svm_cid && + vmci_transport.get_local_cid() != VMADDR_CID_LOCAL))) { + drop_pkt = true; + err = VMCI_ERROR_NO_ACCESS; + } else { + /* The local context ID may be out of date, update it. */ + vsk->local_addr.svm_cid = dst.svm_cid; - if (sk->sk_state == TCP_ESTABLISHED) - vmci_trans(vsk)->notify_ops->handle_notify_pkt( - sk, pkt, true, &dst, &src, - &bh_process_pkt); + if (sk->sk_state == TCP_ESTABLISHED) + vmci_trans(vsk)->notify_ops->handle_notify_pkt(sk, pkt, true, + &dst, &src, + &bh_process_pkt); + } } bh_unlock_sock(sk); + if (drop_pkt) { + if (vmci_transport_send_reset_bh(&dst, &src, pkt) < 0) + pr_err("unable to send reset\n"); + goto out; + } + if (!bh_process_pkt) { struct vmci_transport_recv_pkt_info *recv_pkt_info; @@ -892,6 +909,7 @@ static void vmci_transport_recv_pkt_work(struct work_struct *work) { struct vmci_transport_recv_pkt_info *recv_pkt_info; struct vmci_transport_packet *pkt; + struct sockaddr_vm src; struct sock *sk; recv_pkt_info = @@ -900,6 +918,15 @@ static void vmci_transport_recv_pkt_work(struct work_struct *work) pkt = &recv_pkt_info->pkt; lock_sock(sk); + vsock_addr_init(&src, pkt->dg.src.context, pkt->src_port); + if (sk->sk_state != TCP_LISTEN && + (vsock_sk(sk)->transport != &vmci_transport || + src.svm_port != vsock_sk(sk)->remote_addr.svm_port || + (src.svm_cid != vsock_sk(sk)->remote_addr.svm_cid && + vmci_transport.get_local_cid() != VMADDR_CID_LOCAL))) { + vmci_transport_reply_reset(pkt); + goto out; + } /* The local context ID may be out of date. */ vsock_sk(sk)->local_addr.svm_cid = pkt->dg.dst.context; @@ -929,6 +956,7 @@ static void vmci_transport_recv_pkt_work(struct work_struct *work) break; } +out: release_sock(sk); kfree(recv_pkt_info); /* Release reference obtained in the stream callback when we fetched -- 2.53.0