From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 16B21C43387 for ; Sat, 5 Jan 2019 05:47:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BE75121871 for ; Sat, 5 Jan 2019 05:47:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lca.pw header.i=@lca.pw header.b="LJf6Tdgc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726238AbfAEFrj (ORCPT ); Sat, 5 Jan 2019 00:47:39 -0500 Received: from mail-qk1-f196.google.com ([209.85.222.196]:42918 "EHLO mail-qk1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726102AbfAEFrj (ORCPT ); Sat, 5 Jan 2019 00:47:39 -0500 Received: by mail-qk1-f196.google.com with SMTP id 68so22702704qke.9 for ; Fri, 04 Jan 2019 21:47:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lca.pw; s=google; h=from:to:cc:subject:date:message-id; bh=6m7fySNpjdl7eoTvvjN4S8dxL+B3FXHosc+eNdoBz4A=; b=LJf6TdgcY8QPZDIUSsTDFgpTtxRkr0Qkc+ZAeNHc1pCXKkWX9f3imfrby5pFq3RVQ4 pTUGfekMdIQPNX6Gd2ssV71ZBH4OFxnEnbq6RYdxulo/CXGPKNwr9O4VDML9BmOnjraH jvnLeZrZbzdQsMeoRi1ZUr2f4ZzD0ZtE/WKEvBxPyGBmjmhUbluZ5rvRKvIYO5Obh/fE mE3mbKOrj3+BjQMfM58gLxvXmDeMYq7z7kp0jH5tEx/uZBIxKwbiC9e2hxt5u7S6D2MV LChnMJu7moQ0oHKp9rC118a27lB9bPPnMNisvRdbTx+HQKLdzRyOkHHNR/3y/YIKuhLF esuQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=6m7fySNpjdl7eoTvvjN4S8dxL+B3FXHosc+eNdoBz4A=; b=IrheK1mY9eye0cfU/NcpSghHhrAfwenO3brzg7Iks2EcMjuInxqVq+OTbB9o2ebRa2 Fv1fPWS+eEX0X78kwAuwO8a+f/Ibyia9jZKeQs7/rUxxWW7Pos2I6246HCIUjY23NPpC RnK+TD00JQ/Ni+LyC1fG0kd8uvFnTvOOstz7bmh0rB76psB/tlSjZZVMuaejXMFbHXfM Hr0VvrzP8qAHhh700Jr0rvJ5xnv9PIWvPm5Si44/LEISTlw6myWtZwO8Hb9ij5pTuS71 Lh8u6glD+Sl2A11WKXyJVVYrhcmJgdKa1NJJhsK0Kh2O61oWiwauP7GG1bL1n0ZijAm1 PfMw== X-Gm-Message-State: AJcUukdMkkz/aDCCUu9LG8Lz48WWlI5TvhVOdt8YkoBwbi5Pkh/ll372 J3S3ujzYWNcRciv1rFrEEdgpFw== X-Google-Smtp-Source: ALg8bN5L+wtOajHJzEC5RrnqTnaOKur6ODokvhAYq/L4QVDm00nWsw8IAbC/5MinkvWTRxPbLYaJDw== X-Received: by 2002:a37:4a87:: with SMTP id x129mr49437904qka.142.1546667258411; Fri, 04 Jan 2019 21:47:38 -0800 (PST) Received: from ovpn-120-55.rdu2.redhat.com (pool-71-184-117-43.bstnma.fios.verizon.net. [71.184.117.43]) by smtp.gmail.com with ESMTPSA id a192sm7126324qkg.63.2019.01.04.21.47.37 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 04 Jan 2019 21:47:37 -0800 (PST) From: Qian Cai To: akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, Qian Cai Subject: [PATCH] signal: allow the null signal in rt_sigqueueinfo() Date: Sat, 5 Jan 2019 00:47:29 -0500 Message-Id: <20190105054729.40397-1-cai@lca.pw> X-Mailer: git-send-email 2.17.2 (Apple Git-113) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Running the trinity fuzzer triggered this, UBSAN: Undefined behaviour in kernel/signal.c:2946:7 shift exponent 4294967295 is too large for 64-bit type 'long unsigned int' [ 3752.406618] dump_stack+0xe0/0x17a [ 3752.419817] ubsan_epilogue+0xd/0x4e [ 3752.423429] __ubsan_handle_shift_out_of_bounds+0x1d6/0x227 [ 3752.447269] known_siginfo_layout.cold.9+0x16/0x1b [ 3752.452105] __copy_siginfo_from_user+0x4b/0x70 [ 3752.466620] do_syscall_64+0x164/0x7ea [ 3752.565030] entry_SYSCALL_64_after_hwframe+0x49/0xbe This is because signo is 0 from userspace, and then it ends up calling (1UL << -1) in sig_specific_sicodes(). Since the null signal (0) is allowed in the spec, just deal with it accordingly. Signed-off-by: Qian Cai --- kernel/signal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/signal.c b/kernel/signal.c index e1d7ad8e6ab1..970bb36837a9 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2943,7 +2943,7 @@ static bool known_siginfo_layout(unsigned sig, int si_code) if (si_code == SI_KERNEL) return true; else if ((si_code > SI_USER)) { - if (sig_specific_sicodes(sig)) { + if (sig && sig_specific_sicodes(sig)) { if (si_code <= sig_sicodes[sig].limit) return true; } -- 2.17.2 (Apple Git-113)