From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f78.google.com (mail-ot1-f78.google.com [209.85.210.78]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D16891A268 for ; Fri, 7 Aug 2026 00:01:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.78 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786060896; cv=none; b=YBzKDj/fR7ar8uO8cEApKyAhXtPQFxyO3+sN1x5gzeCyal9LZCzI0K0+uGRGDLduuUF6kBrm/r548zIP/FgUVuMYyrGYTiNMZQEs8BI5v+fTcKczuIq9iG2uxqAZMTsJZvvQcUzRr76LGjk220aBD+guNkP0wWKk9IsRDRNJ2zY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786060896; c=relaxed/simple; bh=73HqpWVFdYJ4Y4Tw7ATgyLoYlrGRqb5MMMfQ3g44pwA=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=mGTGmbiKBYT08qrwvK00BhBTdB/i6e0WYf0wjvZjXOq5TZooumwBNAPUB3mJQhXwmxUqUwIrhv2JBslmT9RuRiTpyFdtRFECdEUmhmxKhrJc5B/ySma7IAKkSXHUZEVUm+J93qQAM5q2PmMwbvd73jUVZH+/93zcUylUqObXx84= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.210.78 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-ot1-f78.google.com with SMTP id 46e09a7af769-7e99ff505c2so1645101a34.1 for ; Thu, 06 Aug 2026 17:01:33 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1786060892; x=1786665692; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=GfN1QcOLKkE6f4SQ8/MOLAZKM4TDMu6M26J6J6oRM+U=; b=cUA40eZHzOUINTz42znp8hW89p3MEzBTBBajVUf+AURyxBcie3eIVOrEzz8mmAu9lg ZCCo47PC9Ht7OXg1ZZUoUDCQhh2KF9LrmokMy980HQGHdJOwNhSq+9YOxzinRWZ1UFl8 d6SkT61i7Wx53NEM7ppTrr4GEb0bjAfEnVbggI4LMNXtMF6n67AgtHdmB2cQQVwntvdF FWVzIK7SZhdrzKl4EWK0sVKsrWlaFFCrlfemBS+AFA0uvOR6kGdiygnHtM7iYsFK/VGh uZ6Urt5LICxYaF5K+FQs/oh0cAUnUdaRpAl+nCk2RX4e7DhuQPw9F2HVpX3g/zZzdDXS K/zw== X-Forwarded-Encrypted: i=1; AHgh+RqnSikzFwNJLJHIvS9O3GhpstFQBxTEms2ZJlM2GhBzTl/kN/Bbo+o6eQwQvH8zIYjsmXvLvVuPEjqCvWU=@vger.kernel.org X-Gm-Message-State: AOJu0YxKWbdTV+p325xUKga6/R2VS/FIzDLwARN7ZFXFZTzt58odR/47 jYOmqWmUo5boUS/x39/lcO1NVagnBJCa1qFpXG+u2KvQqKoVZlvOW+wRRlxUmNTh3zJlfEkVXvV 4Olp0Hsxaw0hQL1t6F9bnVdAPfbqFLVbp21J7x1eX62f/8y44DhyKAk2kG8c= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:f024:b0:6af:f3a3:7f5d with SMTP id 006d021491bc7-6aff3a486f6mr4081860eaf.26.1786060892556; Thu, 06 Aug 2026 17:01:32 -0700 (PDT) Date: Thu, 06 Aug 2026 17:01:32 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a75205c.01d0871a.3a0d52.0032.GAE@google.com> Subject: [syzbot] [fbdev?] KASAN: global-out-of-bounds Read in soft_cursor (3) From: syzbot To: deller@gmx.de, dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, simona@ffwll.ch, syzkaller-bugs@googlegroups.com, tzimmermann@suse.de Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: c2a9495bd873 Merge branch 'for-next/core' into for-kernelci git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci console output: https://syzkaller.appspot.com/x/log.txt?x=123f2986580000 kernel config: https://syzkaller.appspot.com/x/.config?x=a4a42e870a0b0ae0 dashboard link: https://syzkaller.appspot.com/bug?extid=61b1db46218109869c14 compiler: Debian clang version 22.1.6 (++20260514074242+fc4aad7b5db3-1~exp1~20260514074407.73), Debian LLD 22.1.6 userspace arch: arm64 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/03cd82d06e64/disk-c2a9495b.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/bef502845f71/vmlinux-c2a9495b.xz kernel image: https://storage.googleapis.com/syzbot-assets/e14ed9394125/Image-c2a9495b.gz.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+61b1db46218109869c14@syzkaller.appspotmail.com ================================================================== BUG: KASAN: global-out-of-bounds in soft_cursor+0x378/0x6bc drivers/video/fbdev/core/softcursor.c:70 Read of size 16 at addr ffff800086c57970 by task syz.7.609/8216 CPU: 0 UID: 0 PID: 8216 Comm: syz.7.609 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 print_address_description+0xb0/0x238 mm/kasan/report.c:378 print_report+0x68/0x84 mm/kasan/report.c:482 kasan_report+0x8c/0xc4 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x17c/0x1ac mm/kasan/generic.c:200 __asan_memcpy+0x3c/0x84 mm/kasan/shadow.c:105 soft_cursor+0x378/0x6bc drivers/video/fbdev/core/softcursor.c:70 bit_cursor+0xa90/0x1108 drivers/video/fbdev/core/bitblit.c:365 fbcon_cursor+0x344/0x498 drivers/video/fbdev/core/fbcon.c:1427 hide_cursor+0xdc/0x2d0 drivers/tty/vt/vt.c:883 update_region+0x100/0x18c drivers/tty/vt/vt.c:669 vcs_write+0x8ec/0xaf0 drivers/tty/vt/vc_screen.c:685 do_loop_readv_writev+0x24c/0x3dc fs/read_write.c:-1 vfs_writev+0x2c8/0x630 fs/read_write.c:1061 do_writev+0x134/0x2a8 fs/read_write.c:1105 __do_sys_writev fs/read_write.c:1173 [inline] __se_sys_writev fs/read_write.c:1170 [inline] __arm64_sys_writev+0x80/0x94 fs/read_write.c:1170 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594 The buggy address belongs to the variable: fontdata_8x16+0x1010/0x1480 The buggy address belongs to a vmalloc virtual mapping The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x219857 flags: 0x5ffc00000002000(reserved|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000002000 fffffdffc76615c8 fffffdffc76615c8 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff800086c57800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff800086c57880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff800086c57900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f9 f9 ^ ffff800086c57980: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 ffff800086c57a00: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 ================================================================== --- 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. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup