From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f70.google.com (mail-io1-f70.google.com [209.85.166.70]) (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 92A1115B551 for ; Tue, 6 Aug 2024 03:41:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.70 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722915694; cv=none; b=TieyMJb70CeEtqGb+43jjiscdcMyFU2xMCqnG6NqOgdaLBKBzajwQNpS7PGcXGpi1xwrzAvlUqfKkBV6bxgGhRHOt9pWMEAxwih8UzJfjb8IWNy2Xxo6RGucjGjf93byP6F8J/DaB9YTkvbvpONa4OllZE6K0pKgN2u+5iMLDDk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722915694; c=relaxed/simple; bh=cfJnQiGRiLNZZXQ0U5w+PwTLBxMbYLy4nYGq0lhTmtA=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=pkKyo+OWk3qsUCRPF3tOQWHK4lbmonBfQGVxLKhsnvCl/uTLcQ56Unp6ksLYJ6jRCsyaKppnXyAotdtin/ZKtOFxdO7Wf2Kt+TS33VpUCIIXYZvg5nDx8Qdc/UJ/4WtY6lRzWyqa4eYNPg0cwpDiE9aclkapecPwNoGNUyAGcVw= 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=209.85.166.70 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-io1-f70.google.com with SMTP id ca18e2360f4ac-8223aed779aso13155839f.1 for ; Mon, 05 Aug 2024 20:41:29 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1722915688; x=1723520488; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=+JgjY7BMDnfPKZwhOPFpQUnmBA2Ec1+1za4jsL4wAJQ=; b=d9OmUifSrAlmDPgnThDSwuHb9MlJyyzh0kq+LuOjevHM9swY+K+4ef4rXCjFZN5BTk NlUuex3f9Od+0uXWzLG+EUXcnvLF5x3KBA69il/YoSejN8ZAjyOv5YdQtufB9NBFgZFl 1HGwTjb4gUCjrCOSgntbybOoK8x776V3dXUiuj4ma6gdZgaizL0UmKveiK4frhdzhsgf p6kZ3S16jNbR6gELrPdLmACysEeqS7v897d8jXFLFTqBQJTvDvWUO2h/TFxLJ+MVxoab DHK/VN//weqRmgHaTXGnP7J59nyB6ayZiFcHCFG3wS5LAJz8eBH03N+9lFCtySFAvBV5 SYgw== X-Forwarded-Encrypted: i=1; AJvYcCV1udj+oneH/HS/5NP3LES4YnjwBbYSXrb7LqNM/CpValq9N2ytgtKAf+sNOHL4wJSjBbUvjyHn0/5pMHr3JnCDIaHgvts8/JMmfAZB X-Gm-Message-State: AOJu0YzOvTlzDDmGlL3OdXp2q+/h79zNfbd6xx2DTRB7T34oywExiucn TsSDFYRhiT7fLu/ZkfEL+z95OY68IEPFD4efK7ucIb0qHNxvQeh+oaShHDKoFTIDpwN7x/mi185 Jac5kFAldWau5MLkHW74riQ4tKt6OnPcZiR77/2JzkcvcJxZROCDHcAY= X-Google-Smtp-Source: AGHT+IHVoYK2/OVOYfaCo3woMIImP2h9pp6CXglXCHeHvltXb/LLj4+pMMWRpDNkZbvLbobZk6o6fEUrr3wCaF6/0T5/FXmYvXI4 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6638:8911:b0:4c2:7a26:278b with SMTP id 8926c6da1cb9f-4c8d56af0b0mr362481173.5.1722915688467; Mon, 05 Aug 2024 20:41:28 -0700 (PDT) Date: Mon, 05 Aug 2024 20:41:28 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000096e011061efb915b@google.com> Subject: [syzbot] [serial?] KMSAN: uninit-value in n_tty_lookahead_flow_ctrl (2) From: syzbot To: gregkh@linuxfoundation.org, jirislaby@kernel.org, linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 17712b7ea075 Merge tag 'io_uring-6.11-20240802' of git://g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10bc6e75980000 kernel config: https://syzkaller.appspot.com/x/.config?x=9d6059ad10dde6fd dashboard link: https://syzkaller.appspot.com/bug?extid=290abdcd4f509377a0eb compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/8ab4fb08b298/disk-17712b7e.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/22441c38ffc1/vmlinux-17712b7e.xz kernel image: https://storage.googleapis.com/syzbot-assets/faf4575a6197/bzImage-17712b7e.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+290abdcd4f509377a0eb@syzkaller.appspotmail.com ===================================================== BUG: KMSAN: uninit-value in n_tty_lookahead_flow_ctrl+0x2cd/0x300 drivers/tty/n_tty.c:1516 n_tty_lookahead_flow_ctrl+0x2cd/0x300 drivers/tty/n_tty.c:1516 tty_port_default_lookahead_buf+0x144/0x210 drivers/tty/tty_port.c:59 lookahead_bufs drivers/tty/tty_buffer.c:428 [inline] flush_to_ldisc+0x8ec/0xdb0 drivers/tty/tty_buffer.c:498 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xae0/0x1c40 kernel/workqueue.c:3312 worker_thread+0xea5/0x1520 kernel/workqueue.c:3390 kthread+0x3dd/0x540 kernel/kthread.c:389 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Uninit was created at: slab_post_alloc_hook mm/slub.c:3994 [inline] slab_alloc_node mm/slub.c:4037 [inline] __do_kmalloc_node mm/slub.c:4157 [inline] __kmalloc_noprof+0x661/0xf30 mm/slub.c:4170 kmalloc_noprof include/linux/slab.h:685 [inline] tty_buffer_alloc drivers/tty/tty_buffer.c:180 [inline] __tty_buffer_request_room+0x36e/0x6d0 drivers/tty/tty_buffer.c:273 __tty_insert_flip_string_flags+0x140/0x570 drivers/tty/tty_buffer.c:309 tty_insert_flip_char include/linux/tty_flip.h:77 [inline] uart_insert_char+0x39e/0xa10 drivers/tty/serial/serial_core.c:3560 serial8250_read_char+0x1a7/0x5d0 drivers/tty/serial/8250/8250_port.c:1743 serial8250_rx_chars drivers/tty/serial/8250/8250_port.c:1760 [inline] serial8250_handle_irq+0x77a/0xb80 drivers/tty/serial/8250/8250_port.c:1924 serial8250_default_handle_irq+0x120/0x2b0 drivers/tty/serial/8250/8250_port.c:1949 serial8250_interrupt+0xc5/0x360 drivers/tty/serial/8250/8250_core.c:86 __handle_irq_event_percpu+0x118/0xca0 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xef/0x2c0 kernel/irq/handle.c:210 handle_edge_irq+0x340/0xfb0 kernel/irq/chip.c:831 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq arch/x86/kernel/irq.c:247 [inline] call_irq_handler arch/x86/kernel/irq.c:259 [inline] __common_interrupt+0x97/0x1f0 arch/x86/kernel/irq.c:285 common_interrupt+0x8f/0xa0 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x2b/0x40 arch/x86/include/asm/idtentry.h:693 CPU: 0 UID: 0 PID: 3456 Comm: kworker/u8:20 Not tainted 6.11.0-rc1-syzkaller-00272-g17712b7ea075 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: events_unbound flush_to_ldisc ===================================================== --- 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