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=-8.7 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=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 C5B7EC433E1 for ; Fri, 21 Aug 2020 17:02:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9427320702 for ; Fri, 21 Aug 2020 17:02:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728650AbgHURCO (ORCPT ); Fri, 21 Aug 2020 13:02:14 -0400 Received: from mail-io1-f72.google.com ([209.85.166.72]:33665 "EHLO mail-io1-f72.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728515AbgHUQ5S (ORCPT ); Fri, 21 Aug 2020 12:57:18 -0400 Received: by mail-io1-f72.google.com with SMTP id k4so1599518iop.0 for ; Fri, 21 Aug 2020 09:57:17 -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=CvdOFPnjNHrLGNI41Gkr86CDj4Nhfk/ve6MOWKCdqI4=; b=E0XPouQ6OqPlASDJhXXgGNm3gfyZ032WUxfXbCkGEmaFqOniC5osvXl9VkZKCzCMKl qV5770phPcksiGmRqF+kA93ZabzhBDSecAIg991p9OWTCooPGHoAqGBbI3bqI3aXFn48 Nx1pvmoAGp426r8sECJc+zlyLJ2+ULzROlwHbTSBPFWmUmwolvarOiaEne6oA4iTXM0N HK3kZuwC7hERjuvyKZr1D45MiCUjTJXnmBDKrBri1/fy+GIqTBGfiANXXOFqqlRxwIQL D5zhDQ6NqepAywelsmcsAF8NJQufjHrSGPANF6X4P9Kh6xFUNHgG0YJz+yMP/YnXI7sD jXig== X-Gm-Message-State: AOAM531w1AJ0aNUtVA2kUd/pQ1yL+Rf1mNJf+F6k1u6Pd+W7818IugC/ yqK/xL/Y6xtVbdqF6N1pL+xQ0CCE0JyU5L1+Ne4Nkz87ZCe4 X-Google-Smtp-Source: ABdhPJwnLF1JSEy/BMFUX+6YCPwWlT2I3/1MEUwTWHXay6Ld+7lOXwAvqjPm+aCGEqEPFfSv0pZNSEsbG7dgHORND7OVHFM/rb0+ MIME-Version: 1.0 X-Received: by 2002:a92:d8c2:: with SMTP id l2mr3372145ilo.301.1598029036426; Fri, 21 Aug 2020 09:57:16 -0700 (PDT) Date: Fri, 21 Aug 2020 09:57:16 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000000eb21105ad66213f@google.com> Subject: KMSAN: uninit-value in cfb_imageblit From: syzbot To: b.zolnierkie@samsung.com, dri-devel@lists.freedesktop.org, glider@google.com, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.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 issue on: HEAD commit: ce8056d1 wip: changed copy_from_user where instrumented git tree: https://github.com/google/kmsan.git master console output: https://syzkaller.appspot.com/x/log.txt?x=16e7dba1900000 kernel config: https://syzkaller.appspot.com/x/.config?x=3afe005fb99591f dashboard link: https://syzkaller.appspot.com/bug?extid=50bc4646cbe1b0a9a08b compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+50bc4646cbe1b0a9a08b@syzkaller.appspotmail.com ===================================================== BUG: KMSAN: uninit-value in fast_imageblit drivers/video/fbdev/core/cfbimgblt.c:256 [inline] BUG: KMSAN: uninit-value in cfb_imageblit+0x1c71/0x2a60 drivers/video/fbdev/core/cfbimgblt.c:300 CPU: 1 PID: 32379 Comm: syz-executor.1 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+0x21c/0x280 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 fast_imageblit drivers/video/fbdev/core/cfbimgblt.c:256 [inline] cfb_imageblit+0x1c71/0x2a60 drivers/video/fbdev/core/cfbimgblt.c:300 vga16fb_imageblit+0xda2/0x20c0 drivers/video/fbdev/vga16fb.c:1250 soft_cursor+0x12bc/0x13f0 drivers/video/fbdev/core/softcursor.c:74 bit_cursor+0x38c6/0x3a40 drivers/video/fbdev/core/bitblit.c:386 fbcon_cursor+0x195e/0x1a60 drivers/video/fbdev/core/fbcon.c:1411 hide_cursor+0xdd/0x560 drivers/tty/vt/vt.c:902 do_con_write+0x33c/0x15460 drivers/tty/vt/vt.c:2617 con_write+0x8e/0xe0 drivers/tty/vt/vt.c:3159 process_output_block drivers/tty/n_tty.c:595 [inline] n_tty_write+0x167a/0x2230 drivers/tty/n_tty.c:2333 do_tty_write drivers/tty/tty_io.c:962 [inline] tty_write+0x9fb/0x1610 drivers/tty/tty_io.c:1046 vfs_write+0x6a3/0x17c0 fs/read_write.c:576 ksys_write+0x275/0x500 fs/read_write.c:631 __do_sys_write fs/read_write.c:643 [inline] __se_sys_write+0x92/0xb0 fs/read_write.c:640 __ia32_sys_write+0x4a/0x70 fs/read_write.c:640 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2af/0x480 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7f88549 Code: Bad RIP value. RSP: 002b:00000000f55820cc EFLAGS: 00000296 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000200000c0 RDX: 0000000000000078 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 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 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165 __fb_pad_aligned_buffer include/linux/fb.h:655 [inline] fb_pad_aligned_buffer+0x7c4/0x8e0 drivers/video/fbdev/core/fbmem.c:116 soft_cursor+0x1224/0x13f0 drivers/video/fbdev/core/softcursor.c:72 bit_cursor+0x38c6/0x3a40 drivers/video/fbdev/core/bitblit.c:386 fbcon_cursor+0x195e/0x1a60 drivers/video/fbdev/core/fbcon.c:1411 hide_cursor+0xdd/0x560 drivers/tty/vt/vt.c:902 do_con_write+0x33c/0x15460 drivers/tty/vt/vt.c:2617 con_write+0x8e/0xe0 drivers/tty/vt/vt.c:3159 process_output_block drivers/tty/n_tty.c:595 [inline] n_tty_write+0x167a/0x2230 drivers/tty/n_tty.c:2333 do_tty_write drivers/tty/tty_io.c:962 [inline] tty_write+0x9fb/0x1610 drivers/tty/tty_io.c:1046 vfs_write+0x6a3/0x17c0 fs/read_write.c:576 ksys_write+0x275/0x500 fs/read_write.c:631 __do_sys_write fs/read_write.c:643 [inline] __se_sys_write+0x92/0xb0 fs/read_write.c:640 __ia32_sys_write+0x4a/0x70 fs/read_write.c:640 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2af/0x480 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c 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 soft_cursor+0x7d7/0x13f0 drivers/video/fbdev/core/softcursor.c:70 bit_cursor+0x38c6/0x3a40 drivers/video/fbdev/core/bitblit.c:386 fbcon_cursor+0x195e/0x1a60 drivers/video/fbdev/core/fbcon.c:1411 hide_cursor+0xdd/0x560 drivers/tty/vt/vt.c:902 do_con_write+0x33c/0x15460 drivers/tty/vt/vt.c:2617 con_write+0x8e/0xe0 drivers/tty/vt/vt.c:3159 process_output_block drivers/tty/n_tty.c:595 [inline] n_tty_write+0x167a/0x2230 drivers/tty/n_tty.c:2333 do_tty_write drivers/tty/tty_io.c:962 [inline] tty_write+0x9fb/0x1610 drivers/tty/tty_io.c:1046 vfs_write+0x6a3/0x17c0 fs/read_write.c:576 ksys_write+0x275/0x500 fs/read_write.c:631 __do_sys_write fs/read_write.c:643 [inline] __se_sys_write+0x92/0xb0 fs/read_write.c:640 __ia32_sys_write+0x4a/0x70 fs/read_write.c:640 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2af/0x480 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline] kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80 slab_alloc_node mm/slub.c:2839 [inline] slab_alloc mm/slub.c:2848 [inline] __kmalloc+0x312/0x410 mm/slub.c:3911 kmalloc include/linux/slab.h:560 [inline] fbcon_set_font+0x5ad/0xfb0 drivers/video/fbdev/core/fbcon.c:2673 con_font_set drivers/tty/vt/vt.c:4571 [inline] con_font_op+0x1e59/0x2290 drivers/tty/vt/vt.c:4636 vt_ioctl+0x99e/0x67c0 drivers/tty/vt/vt_ioctl.c:917 vt_compat_ioctl+0x59b/0x1040 drivers/tty/vt/vt_ioctl.c:1242 tty_compat_ioctl+0x74b/0x1660 drivers/tty/tty_io.c:2847 __do_compat_sys_ioctl fs/ioctl.c:847 [inline] __se_compat_sys_ioctl+0x55f/0x1100 fs/ioctl.c:798 __ia32_compat_sys_ioctl+0x4a/0x70 fs/ioctl.c:798 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2af/0x480 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c ===================================================== --- This report is generated by a bot. 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