From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 827F143CEC0; Mon, 17 Aug 2026 13:56:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786974992; cv=none; b=dymKhZaL2QYP/ZyynhfUx9jn0ZZhJim/0FE1EaKBZyp4bPXZkLdBzQUum+d9wwJjfYpHrZI5jJWFnsnG9Cz8WtmjKpuiDHRxyoI390Q0pD/QABkHVLI40oxiRHi+kljVFyxV8M3LYrc6smEFzH0nJEKURE0Fhm3QIVMWSHsV73E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786974992; c=relaxed/simple; bh=VBxjettDFkSMEQz7GNjlQHFutjlGkV23lEq4EmD1xWM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Q/Ual0z4w80uJy2g9KxLMGojjEg7mtn8XUJGh8Equt//c496upStVZYcU46OUn9MrWovK9sB8H6SIU9ethNV5EYFfkcmg2WiGuLeqDYpuLJ/sCXR6scBSXa2fvWyuRXSo/E7yQjxLk25vI3JtDfCVaWTIoVY04rMCTyPKH6yiqw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=GSPoun2z; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="GSPoun2z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8932C1F000E9; Mon, 17 Aug 2026 13:56:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786974987; bh=UDiOjzDeQPffNDN/R900CpaExggcLd3lligiCz9P5ts=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=GSPoun2zWxkYmD3W8ozBhamJ0D7wH5g1qrSTlzSEieSuylWUxCIRuyVetWwDJY6jN QvQZo3IvBdYYwxJjV9r/lRQbTtJlHAdlYTvEXgBWCYtT3O/CuAEMYmatLE0sIC2ZOU uQBSqfZP1EqjBKGzbo2rrQnfEn5YW6vOkv35fvJo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Joshua Rogers , stable Subject: [PATCH 6.18 124/250] vt: stabilize tty reference in kbd_keycode with tty_port_tty_get Date: Mon, 17 Aug 2026 15:31:25 +0200 Message-ID: <20260817132541.664467915@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132536.466235697@linuxfoundation.org> References: <20260817132536.466235697@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Joshua Rogers commit e25d47a526939ad44b75f778b8a7500562b84fc1 upstream. kbd_keycode() reads vc->port.tty without acquiring a tty reference, racing against con_shutdown() which clears port.tty under a different lock. Use tty_port_tty_get()/tty_kref_put() to hold a proper reference for the duration the tty pointer is needed. Assisted-by: AISLE:Snapshot Signed-off-by: Joshua Rogers Cc: stable Link: https://patch.msgid.link/20260731-tty-vt-stuff-v1-1-be99b9da8e30@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- drivers/tty/vt/keyboard.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/drivers/tty/vt/keyboard.c +++ b/drivers/tty/vt/keyboard.c @@ -1396,7 +1396,7 @@ static void kbd_keycode(unsigned int key struct keyboard_notifier_param param = { .vc = vc, .value = keycode, .down = down }; int rc; - tty = vc->port.tty; + tty = tty_port_tty_get(&vc->port); if (tty && (!tty->driver_data)) { /* No driver data? Strange. Okay we fix it then. */ @@ -1456,9 +1456,12 @@ static void kbd_keycode(unsigned int key * characters get aren't echoed locally. This makes key repeat * usable with slow applications and under heavy loads. */ + tty_kref_put(tty); return; } + tty_kref_put(tty); + param.shift = shift_final = (shift_state | kbd->slockstate) ^ kbd->lockstate; param.ledstate = kbd->ledflagstate; key_map = key_maps[shift_final];