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=-5.4 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 DED09C433E0 for ; Mon, 6 Jul 2020 06:22:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C1E452075B for ; Mon, 6 Jul 2020 06:22:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728828AbgGFGWQ (ORCPT ); Mon, 6 Jul 2020 02:22:16 -0400 Received: from mail-io1-f72.google.com ([209.85.166.72]:45218 "EHLO mail-io1-f72.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728863AbgGFGWP (ORCPT ); Mon, 6 Jul 2020 02:22:15 -0400 Received: by mail-io1-f72.google.com with SMTP id d64so22871225iof.12 for ; Sun, 05 Jul 2020 23:22:14 -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=65VFK3CeGOY6XsF4+JQsV3Lwx5hkLbk2n9tjz+Qw9Jo=; b=f2mmBoi88CHxYsqn8hfKEjbyBJMNILLVeUIzA3NFBgSYSVHJRf47PfEDk2MIi5jr0X +jNeEKmdhnbc4IN7UsRmpM88U7BYCpSOL7T+4AfjPaDCOCMcS91PLo34Y1j3m6SLxyno hMocNLWgS8ogqIjXr4/r60JWic7PxzCPVj4nfGr6VhYBDe0EqQuV5IwPaEYE4ySlK8UL jxkVlbK1h7IVeVhZgdYB4cfto6dtPozenqdT/1OBqfuR+fRkz6kLj6qnP3UBXp/C8C4U tEhN4Yi5lNmSms8BQIsdILvbrspK9nufen+rPn7iFc3kIgahuCVCc37uohiRlDM8/KyG TJNg== X-Gm-Message-State: AOAM530tOTC7BVbbwl3I+ic3WXmKeDN6A7IbmDTx331Ppm634FUZzmSc 4mEdH0olLzLCEs19EPs/CcFIraqJ+xIPgOD0JDkRDy8V5xZz X-Google-Smtp-Source: ABdhPJzxJfprkEfzW1CDLFjw0CpuAk9bdct5cThB4k/Pgp3XcKi4EsWkOqKoaALvUQgTFtVbA7bcf/rlB1rqsD1zoXgBN1gbx34K MIME-Version: 1.0 X-Received: by 2002:a92:b749:: with SMTP id c9mr30062467ilm.289.1594016534226; Sun, 05 Jul 2020 23:22:14 -0700 (PDT) Date: Sun, 05 Jul 2020 23:22:14 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000049f07f05a9bfe509@google.com> Subject: KASAN: use-after-free Read in wg_get_device_start From: syzbot To: Jason@zx2c4.com, davem@davemloft.net, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com, wireguard@lists.zx2c4.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: 7cc2a8ea Merge tag 'block-5.8-2020-07-01' of git://git.ker.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=123532a7100000 kernel config: https://syzkaller.appspot.com/x/.config?x=183dd243398ba7ec dashboard link: https://syzkaller.appspot.com/bug?extid=e869cfbeeae05d706b9c compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+e869cfbeeae05d706b9c@syzkaller.appspotmail.com ================================================================== BUG: KASAN: use-after-free in nla_get_u32 include/net/netlink.h:1541 [inline] BUG: KASAN: use-after-free in lookup_interface drivers/net/wireguard/netlink.c:61 [inline] BUG: KASAN: use-after-free in wg_get_device_start+0x2bc/0x2d0 drivers/net/wireguard/netlink.c:203 Read of size 4 at addr ffff88803b9c3818 by task syz-executor.3/15521 CPU: 1 PID: 15521 Comm: syz-executor.3 Not tainted 5.8.0-rc3-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+0x1f0/0x31e lib/dump_stack.c:118 print_address_description+0x66/0x5a0 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report+0x132/0x1d0 mm/kasan/report.c:530 nla_get_u32 include/net/netlink.h:1541 [inline] lookup_interface drivers/net/wireguard/netlink.c:61 [inline] wg_get_device_start+0x2bc/0x2d0 drivers/net/wireguard/netlink.c:203 genl_start+0x390/0x570 net/netlink/genetlink.c:556 __netlink_dump_start+0x3d2/0x700 net/netlink/af_netlink.c:2343 genl_family_rcv_msg_dumpit net/netlink/genetlink.c:638 [inline] genl_family_rcv_msg net/netlink/genetlink.c:733 [inline] genl_rcv_msg+0xb03/0xe00 net/netlink/genetlink.c:753 netlink_rcv_skb+0x190/0x3a0 net/netlink/af_netlink.c:2469 genl_rcv+0x24/0x40 net/netlink/genetlink.c:764 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x786/0x940 net/netlink/af_netlink.c:1329 netlink_sendmsg+0xa57/0xd70 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x519/0x800 net/socket.c:2352 ___sys_sendmsg net/socket.c:2406 [inline] __sys_sendmsg+0x2b1/0x360 net/socket.c:2439 do_syscall_64+0x73/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cb29 Code: Bad RIP value. RSP: 002b:00007f1bd1266c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000502320 RCX: 000000000045cb29 RDX: 0000000000000000 RSI: 0000000020000200 RDI: 0000000000000003 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000a32 R14: 00000000004cd184 R15: 00007f1bd12676d4 Allocated by task 15525: save_stack mm/kasan/common.c:48 [inline] set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc+0x103/0x140 mm/kasan/common.c:494 __kmalloc_reserve net/core/skbuff.c:142 [inline] __alloc_skb+0xde/0x4f0 net/core/skbuff.c:210 alloc_skb include/linux/skbuff.h:1083 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1175 [inline] netlink_sendmsg+0x7b2/0xd70 net/netlink/af_netlink.c:1893 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x519/0x800 net/socket.c:2352 ___sys_sendmsg net/socket.c:2406 [inline] __sys_sendmsg+0x2b1/0x360 net/socket.c:2439 do_syscall_64+0x73/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 15525: save_stack mm/kasan/common.c:48 [inline] set_track mm/kasan/common.c:56 [inline] kasan_set_free_info mm/kasan/common.c:316 [inline] __kasan_slab_free+0x114/0x170 mm/kasan/common.c:455 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x220 mm/slab.c:3757 skb_release_all net/core/skbuff.c:664 [inline] __kfree_skb+0x56/0x1c0 net/core/skbuff.c:678 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x78e/0x940 net/netlink/af_netlink.c:1329 netlink_sendmsg+0xa57/0xd70 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x519/0x800 net/socket.c:2352 ___sys_sendmsg net/socket.c:2406 [inline] __sys_sendmsg+0x2b1/0x360 net/socket.c:2439 do_syscall_64+0x73/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff88803b9c3800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 24 bytes inside of 1024-byte region [ffff88803b9c3800, ffff88803b9c3c00) The buggy address belongs to the page: page:ffffea0000ee70c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea0001859248 ffffea0000e02ec8 ffff8880aa400c40 raw: 0000000000000000 ffff88803b9c3000 0000000100000002 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88803b9c3700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88803b9c3780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88803b9c3800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88803b9c3880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88803b9c3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- This bug 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 bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.