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 F18D9435A96; Tue, 21 Jul 2026 20:24:13 +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=1784665455; cv=none; b=pEXtx9m4y8EN2UWsQylZRvnN+bzjoai5IQ0YtesNpJEBAi04k3CzA2F+iLST3JPnmYLQdgtPtZpRl8fjt6Hvsk2Ij/ZS0/jUu3ckXHeekDmWSzTyPVv0sHLYAXkWQKauptXeijXsaiaorK2LEdEopkGngV54l2jWkapeT6fw4Ok= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784665455; c=relaxed/simple; bh=YFFVQiP+tD4dD7wFrfkT23pR6YC1uKi3jXyu47OMPBw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BI1ausDsrhu0WDpOuGKZ31/ux6LX+m6TCRzCzIn3M2h6eLa9Td2/WN5cHLEyq5Pvr2hdcklTQ+/DJZ4kLfPeDQi9sxXdHBNNdC2aCd+s0DVxE4EJuMgKuuoxAhJWS6e0jFG913iqoeQsygd2fC2ivXyvnjcjuhUfoOKQfrmN/qc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ElKhs0sJ; 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="ElKhs0sJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 634F11F00A3A; Tue, 21 Jul 2026 20:24:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784665453; bh=M37iC/zPQ8VvBbcMUUal6ts+YzJvMg00KnlscWq5Ebw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ElKhs0sJh1Dv4jSJHP6gBj1KoColcQEx6M1HvHCwV22+hS1zkRWDQcyeU/kidTO/a evis9DRotAWSqc/TAyAk5sh3UCRkTFj5ZLGjyrSwjBq0wH+2Lpq70Awn4J/0pcKqgj 9/QYoCVI6Nlr4XiYQTNFFxCgaIhTBRIj03taidyw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Bryam Vargas , Hans de Goede , Dmitry Torokhov Subject: [PATCH 6.6 0309/1266] Input: goodix - clamp the device-reported contact count Date: Tue, 21 Jul 2026 17:12:26 +0200 Message-ID: <20260721152448.746985445@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152441.786066624@linuxfoundation.org> References: <20260721152441.786066624@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 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Bryam Vargas commit 5ed62a96e06be4e94b8296b7932afee550a70e04 upstream. goodix_ts_read_input_report() copies the number of touch points reported by the device into an on-stack buffer u8 point_data[2 + GOODIX_MAX_CONTACT_SIZE * GOODIX_MAX_CONTACTS]; which is sized for at most GOODIX_MAX_CONTACTS (10) contacts. The only runtime check bounds the per-interrupt count against ts->max_touch_num, but that value is taken verbatim from a 4-bit field of the device configuration block and is never clamped: ts->max_touch_num = ts->config[MAX_CONTACTS_LOC] & 0x0f; The nibble can be 0..15, so a malfunctioning, malicious or counterfeit controller (or an attacker tampering with the I2C bus) can advertise up to 15 contacts. goodix_ts_read_input_report() then accepts a touch_num of up to 15 and the second goodix_i2c_read() writes ts->contact_size * (touch_num - 1) bytes past the one-contact header into point_data - up to 30 bytes (45 with the 9-byte report format) beyond the 92-byte buffer: a stack out-of-bounds write. Clamp max_touch_num to GOODIX_MAX_CONTACTS, the number of contacts point_data[] is sized for, when reading it from the configuration. Fixes: a7ac7c95d468 ("Input: goodix - use max touch number from device config") Cc: stable@vger.kernel.org Signed-off-by: Bryam Vargas Reviewed-by: Hans de Goede Link: https://patch.msgid.link/20260612-b4-disp-6844625d-v1-1-df0aed080c9d@proton.me Signed-off-by: Dmitry Torokhov Signed-off-by: Greg Kroah-Hartman --- drivers/input/touchscreen/goodix.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/input/touchscreen/goodix.c +++ b/drivers/input/touchscreen/goodix.c @@ -1056,7 +1056,8 @@ static void goodix_read_config(struct go } ts->int_trigger_type = ts->config[TRIGGER_LOC] & 0x03; - ts->max_touch_num = ts->config[MAX_CONTACTS_LOC] & 0x0f; + ts->max_touch_num = min(ts->config[MAX_CONTACTS_LOC] & 0x0f, + GOODIX_MAX_CONTACTS); x_max = get_unaligned_le16(&ts->config[RESOLUTION_LOC]); y_max = get_unaligned_le16(&ts->config[RESOLUTION_LOC + 2]);