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=-0.4 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 C630EC2BD09 for ; Thu, 5 Dec 2019 16:46:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9BD1D21823 for ; Thu, 5 Dec 2019 16:46:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729887AbfLEQqK (ORCPT ); Thu, 5 Dec 2019 11:46:10 -0500 Received: from mail-il1-f200.google.com ([209.85.166.200]:39007 "EHLO mail-il1-f200.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729598AbfLEQqJ (ORCPT ); Thu, 5 Dec 2019 11:46:09 -0500 Received: by mail-il1-f200.google.com with SMTP id v11so2946996ilg.6 for ; Thu, 05 Dec 2019 08:46:08 -0800 (PST) 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=6XRIMuzgh02Ovw3rxeyz54ijBjPe2X9NHJTkVKkX31c=; b=AYYemlZi/S4VbE3aySCcX5tnqj9GnUwl/nlpfn3kOqlYaaqOww70GqMAYWvsnlUVar NNOacVMufXalEO/JURlR7sXCHszxIFW8Pph3uCXz773BQCnqNAIx7hIebPoJwfD1QPTm VZnemHICEr/yn8f11p05Q3QMgQsz7UPsOm33B7/wYJ2VtzE2gTAJwxpIW7ic25ase8lR cavPG3C9S4rgTSGlzOcejqkWFLJY/e2c6oSO1FoqP5cFkgygdTcc/Uea5T/JbfYbMneg bEzyLiEWJCLmZZpsx3J8anSXdQi5h+J5JS6FA3ZBrpxsK6xdzpo43SIXSn4FP1YmYNXw SUqg== X-Gm-Message-State: APjAAAXh35/04v0ufYVgJzY4dNghWb0WfEcw0b+QakFO+PfKKbiyDyGg jppCI93JhSEz1ULz+altiqim4Ltw5heFK5RAgUuVdqsv25Rc X-Google-Smtp-Source: APXvYqxQVnQDUVP2INDpxyPnyG5PtM7v1M6Mm6zZiDrpKRt8Oj8xWWXGWPnM0NftkIPnk0Nc6bZSd6+4j6uheUrk7UGEGl/O9jKS MIME-Version: 1.0 X-Received: by 2002:a02:9f09:: with SMTP id z9mr8888680jal.119.1575564368341; Thu, 05 Dec 2019 08:46:08 -0800 (PST) Date: Thu, 05 Dec 2019 08:46:08 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000007f075c0598f7aa38@google.com> Subject: KASAN: slab-out-of-bounds Read in bit_putcs From: syzbot To: b.zolnierkie@samsung.com, dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes 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: 282ffdf3 Add linux-next specific files for 20191205 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=165627f2e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=29372c0243b4b980 dashboard link: https://syzkaller.appspot.com/bug?extid=998dec6452146bd7a90c compiler: gcc (GCC) 9.0.0 20181231 (experimental) 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+998dec6452146bd7a90c@syzkaller.appspotmail.com ================================================================== BUG: KASAN: slab-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:655 [inline] BUG: KASAN: slab-out-of-bounds in bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] BUG: KASAN: slab-out-of-bounds in bit_putcs+0xd5d/0xf10 drivers/video/fbdev/core/bitblit.c:185 Read of size 1 at addr ffff88809f4ed8fe by task syz-executor.1/22264 CPU: 0 PID: 22264 Comm: syz-executor.1 Not tainted 5.4.0-next-20191205-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+0x197/0x210 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:639 __asan_report_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:132 __fb_pad_aligned_buffer include/linux/fb.h:655 [inline] bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] bit_putcs+0xd5d/0xf10 drivers/video/fbdev/core/bitblit.c:185 fbcon_putcs+0x33c/0x3e0 drivers/video/fbdev/core/fbcon.c:1353 do_update_region+0x42b/0x6f0 drivers/tty/vt/vt.c:677 redraw_screen+0x676/0x7d0 drivers/tty/vt/vt.c:1011 vc_do_resize+0x10c9/0x1460 drivers/tty/vt/vt.c:1284 vc_resize+0x4d/0x60 drivers/tty/vt/vt.c:1304 vt_ioctl+0x2076/0x26d0 drivers/tty/vt/vt_ioctl.c:887 tty_ioctl+0xa37/0x14f0 drivers/tty/tty_io.c:2660 vfs_ioctl fs/ioctl.c:47 [inline] file_ioctl fs/ioctl.c:545 [inline] do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732 ksys_ioctl+0xab/0xd0 fs/ioctl.c:749 __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl fs/ioctl.c:754 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a679 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fce593a0c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a679 RDX: 00000000200002c0 RSI: 000000000000560a RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fce593a16d4 R13: 00000000004c6ce2 R14: 00000000004dd2d0 R15: 00000000ffffffff Allocated by task 18936: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:527 __do_kmalloc mm/slab.c:3656 [inline] __kmalloc+0x163/0x770 mm/slab.c:3665 kmalloc include/linux/slab.h:561 [inline] fbcon_set_font+0x32d/0x860 drivers/video/fbdev/core/fbcon.c:2663 con_font_set drivers/tty/vt/vt.c:4538 [inline] con_font_op+0xe30/0x1270 drivers/tty/vt/vt.c:4603 vt_ioctl+0xd2e/0x26d0 drivers/tty/vt/vt_ioctl.c:913 tty_ioctl+0xa37/0x14f0 drivers/tty/tty_io.c:2660 vfs_ioctl fs/ioctl.c:47 [inline] file_ioctl fs/ioctl.c:545 [inline] do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732 ksys_ioctl+0xab/0xd0 fs/ioctl.c:749 __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl fs/ioctl.c:754 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 18502: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:335 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:474 kasan_slab_free+0xe/0x10 mm/kasan/common.c:483 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x2c0 mm/slab.c:3757 free_event_rcu+0x5e/0x70 kernel/events/core.c:4372 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch kernel/rcu/tree.c:2183 [inline] rcu_core+0x570/0x1540 kernel/rcu/tree.c:2408 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2417 __do_softirq+0x262/0x98c kernel/softirq.c:292 The buggy address belongs to the object at ffff88809f4ed000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 254 bytes to the right of 2048-byte region [ffff88809f4ed000, ffff88809f4ed800) The buggy address belongs to the page: page:ffffea00027d3b40 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 raw: 00fffe0000000200 ffffea00029bc9c8 ffffea00024ae408 ffff8880aa400e00 raw: 0000000000000000 ffff88809f4ed000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809f4ed780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809f4ed800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ffff88809f4ed880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88809f4ed900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809f4ed980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== --- 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.