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=-9.0 required=3.0 tests=BAYES_00,FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 A0F4DC433DF for ; Wed, 22 Jul 2020 06:03:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 817FC20771 for ; Wed, 22 Jul 2020 06:03:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728564AbgGVGDW (ORCPT ); Wed, 22 Jul 2020 02:03:22 -0400 Received: from mail-il1-f198.google.com ([209.85.166.198]:40802 "EHLO mail-il1-f198.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728360AbgGVGDW (ORCPT ); Wed, 22 Jul 2020 02:03:22 -0400 Received: by mail-il1-f198.google.com with SMTP id z16so332819ill.7 for ; Tue, 21 Jul 2020 23:03:21 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=qewiQyGL3IqTi25pirur6TTlTDfT/YuVT6Cr43auRm8=; b=pPdBVYOAS0L5v4vOKShdA9rNSQcetSPVnDS4vPVXQRxmy9zCBvgrYcgaXLohZS/gai m6P54eokvqBas3CvotUwx54S9PxauHpP/Hkfw5+a3HzZ2wOp8O+twy84Jcpg45aNtr8q iripq7rzygDhC+lxpoNtlhGquDHZizskIndQ3CoEI/H7n9t/F4vOvjWloFlK1+YpazPL fdoI8ij/ikhCgfw+ci7NQKjwyqW3QAYn0hp4vd3dgyz52S3bK+3nX9ktDg3cvJ4xLJZ2 BsQSZFJzjUBgxw9eVRaNX4PpsMPaV1sVQqE3Wiw0yFBWjSq07IYDBkAmalvKxYKoN5mp Xj5Q== X-Gm-Message-State: AOAM5312vi5uVX/BxRFbU4ht9xHSy9D42eHXH/FV2ABwXbUTxEEe8pHt QKDvntQzrYFK0eA9mVmpkcOfDXqta8GomYj8fogbboE6P82Q X-Google-Smtp-Source: ABdhPJzYmim9ktgMXkp8pvt6+iCoKQ26mLH8PDcWEiMolCUcUPF8IcgLJl+ryu0e5ThHFcMwy5N58RfE4xkz1f28mvpjn/xoYCF1 MIME-Version: 1.0 X-Received: by 2002:a5e:8f4b:: with SMTP id x11mr29850087iop.90.1595397800692; Tue, 21 Jul 2020 23:03:20 -0700 (PDT) Date: Tue, 21 Jul 2020 23:03:20 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000002f93a705ab017f2c@google.com> Subject: KMSAN: uninit-value in _copy_to_iter (3) From: syzbot To: davem@davemloft.net, glider@google.com, kuba@kernel.org, linux-can@vger.kernel.org, linux-kernel@vger.kernel.org, mkl@pengutronix.de, netdev@vger.kernel.org, socketcan@hartkopp.net, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: 14525656 compiler.h: reinstate missing KMSAN_INIT git tree: https://github.com/google/kmsan.git master console output: https://syzkaller.appspot.com/x/log.txt?x=15996087100000 kernel config: https://syzkaller.appspot.com/x/.config?x=c534a9fad6323722 dashboard link: https://syzkaller.appspot.com/bug?extid=81908a97abeec4f4f02d compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1018fc7f100000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=100846d7100000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+81908a97abeec4f4f02d@syzkaller.appspotmail.com ===================================================== BUG: KMSAN: uninit-value in kmsan_check_memory+0xd/0x10 mm/kmsan/kmsan_hooks.c:428 CPU: 0 PID: 8682 Comm: syz-executor281 Not tainted 5.8.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1df/0x240 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 kmsan_internal_check_memory+0x238/0x3d0 mm/kmsan/kmsan.c:423 kmsan_check_memory+0xd/0x10 mm/kmsan/kmsan_hooks.c:428 instrument_copy_to_user include/linux/instrumented.h:91 [inline] copyout lib/iov_iter.c:142 [inline] _copy_to_iter+0x3d4/0x26e0 lib/iov_iter.c:631 copy_to_iter include/linux/uio.h:138 [inline] memcpy_to_msg include/linux/skbuff.h:3571 [inline] bcm_recvmsg+0x25a/0x740 net/can/bcm.c:1612 sock_recvmsg_nosec net/socket.c:886 [inline] sock_recvmsg net/socket.c:904 [inline] __sys_recvfrom+0xacd/0xae0 net/socket.c:2052 __do_sys_recvfrom net/socket.c:2070 [inline] __se_sys_recvfrom+0x111/0x130 net/socket.c:2066 __x64_sys_recvfrom+0x6e/0x90 net/socket.c:2066 do_syscall_64+0xb0/0x150 arch/x86/entry/common.c:386 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x448cd9 Code: Bad RIP value. RSP: 002b:00007f5fbb95fd88 EFLAGS: 00000246 ORIG_RAX: 000000000000002d RAX: ffffffffffffffda RBX: 00000000006dec68 RCX: 0000000000448cd9 RDX: 0000000000000032 RSI: 0000000020000040 RDI: 0000000000000003 RBP: 00000000006dec60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dec6c R13: ffffff7f00000001 R14: 0000000000000000 R15: 000000306e616376 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline] kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310 kmsan_memcpy_memmove_metadata+0x272/0x2e0 mm/kmsan/kmsan.c:247 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:267 __msan_memcpy+0x43/0x50 mm/kmsan/kmsan_instr.c:116 skb_put_data include/linux/skbuff.h:2260 [inline] bcm_send_to_user+0x250/0x820 net/can/bcm.c:327 bcm_tx_timeout_handler+0x5d0/0x620 net/can/bcm.c:413 __run_hrtimer kernel/time/hrtimer.c:1520 [inline] __hrtimer_run_queues+0xa61/0x1340 kernel/time/hrtimer.c:1584 hrtimer_run_softirq+0x1b2/0x2b0 kernel/time/hrtimer.c:1601 __do_softirq+0x311/0x83d kernel/softirq.c:293 Local variable ----msg_head@bcm_tx_timeout_handler created at: bcm_tx_timeout_handler+0x4f/0x620 net/can/bcm.c:398 bcm_tx_timeout_handler+0x4f/0x620 net/can/bcm.c:398 Bytes 12-15 of 50 are uninitialized Memory access of size 50 starts at ffff88b629809600 ===================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches