From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-io1-f70.google.com ([209.85.166.70]:56781 "EHLO mail-io1-f70.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726609AbeKIArA (ORCPT ); Thu, 8 Nov 2018 19:47:00 -0500 Received: by mail-io1-f70.google.com with SMTP id x12-v6so22711204iob.23 for ; Thu, 08 Nov 2018 07:11:03 -0800 (PST) MIME-Version: 1.0 Date: Thu, 08 Nov 2018 07:11:03 -0800 Message-ID: <000000000000a91c14057a28a4ae@google.com> Subject: KASAN: global-out-of-bounds Read in tpg_print_str_4 From: syzbot To: bwinther@cisco.com, hverkuil@xs4all.nl, keescook@chromium.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, mchehab@kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-media-owner@vger.kernel.org List-ID: Hello, syzbot found the following crash on: HEAD commit: 85758777c2a2 Merge tag 'hwmon-for-v4.20-rc2' of git://git... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=157af45d400000 kernel config: https://syzkaller.appspot.com/x/.config?x=8f559fee2fc3375a dashboard link: https://syzkaller.appspot.com/bug?extid=ccf0a61ed12f2a7313ee compiler: gcc (GCC) 8.0.1 20180413 (experimental) userspace arch: i386 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+ccf0a61ed12f2a7313ee@syzkaller.appspotmail.com ================================================================== BUG: KASAN: global-out-of-bounds in tpg_print_str_4+0xbc9/0xd70 drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:1820 Read of size 1 at addr ffffffff88631c50 by task vivid-000-vid-c/7282 CPU: 0 PID: 7282 Comm: vivid-000-vid-c Not tainted 4.20.0-rc1+ #228 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+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x58/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430 tpg_print_str_4+0xbc9/0xd70 drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:1820 tpg_gen_text+0x4ba/0x540 drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:1874 vivid_fillbuff+0x3ff7/0x68e0 drivers/media/platform/vivid/vivid-kthread-cap.c:532 vivid_thread_vid_cap_tick drivers/media/platform/vivid/vivid-kthread-cap.c:709 [inline] vivid_thread_vid_cap+0xbc1/0x2650 drivers/media/platform/vivid/vivid-kthread-cap.c:813 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 The buggy address belongs to the variable: font_vga_8x16+0x50/0x60 Memory state around the buggy address: ffffffff88631b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffffff88631b80: 00 00 00 00 fa fa fa fa 00 fa fa fa fa fa fa fa > ffffffff88631c00: 00 00 00 00 00 fa fa fa fa fa fa fa 00 00 00 00 ^ ffffffff88631c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffffff88631d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== --- 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#bug-status-tracking for how to communicate with syzbot.