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 54C3543E4BA; Tue, 16 Jun 2026 16:17:03 +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=1781626624; cv=none; b=hUjfT+LENga//UT7yXJOo28k1t7e4YgxN3yLofP8WWifJj0v/PGdVKl6/Pbk9RAJ+HJ5GwNZzMOuIk6S/+q9W5V/J09X8pWEtcFICdPCMTXy7YIPbfG5gd+wI+M0Ii2mxLb3SjQwgLHahOI5QeVL/Wm4KRsclMcysQ+1+vg2flU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781626624; c=relaxed/simple; bh=+BmwlgMb6lMAY62jAEEUXbMaeS1ye2HxxGgNt0DioAQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=PHboHV5Lmwo91u4JmTTAMXpkU/hlB3QrYa9AZkMct3LpA+/ztaMjWqhflZWxVwTFXyy3QafQudI8I8zM0a7Q4vYkvDLL/bmN/Jde3j+loVJKZ/FzLr4Jk/eM6/WIC4wwqS3YspBZlFNOpDpm3uCIv8d2w05KsiGB37YcDSG3ABw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=DrkUJjpa; 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="DrkUJjpa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 554541F000E9; Tue, 16 Jun 2026 16:17:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781626623; bh=6MDmVAhpWPsAlnlivbx36HW3AI29lAeRAydBPWjrCMM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=DrkUJjpaPMNtvctgnYL/CquQs0xnkzY24z2Srr8nyOC5c/fMl29cb15AlfI55WyWV dGea1cr++rWJpcxMBLXLxJhKg/e6Lxc9mLxrZCneSie+4FG3rOwjh0xBjDm2K7hqbZ OgrBjWGmLGiskdgfK1MHh773ZZG2JyPRbucQa9CI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Paul Menzel , Zhang Cen , Luiz Augusto von Dentz , Sasha Levin Subject: [PATCH 6.12 038/261] Bluetooth: MGMT: validate advertising TLV before type checks Date: Tue, 16 Jun 2026 20:27:56 +0530 Message-ID: <20260616145046.897611487@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145044.869532709@linuxfoundation.org> References: <20260616145044.869532709@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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Zhang Cen [ Upstream commit de23fb62259aa01d294f77238ae3b835eb674413 ] tlv_data_is_valid() reads each advertising data field length from data[i], then inspects data[i + 1] for managed EIR types before checking that the current field still fits inside the supplied buffer. A malformed field whose length byte is the last byte of the buffer can therefore make the parser read one byte past the advertising data. KASAN reported the following when a malformed MGMT_OP_ADD_ADVERTISING request reached that path: BUG: KASAN: vmalloc-out-of-bounds in tlv_data_is_valid() Read of size 1 Call trace: tlv_data_is_valid() add_advertising() hci_mgmt_cmd() hci_sock_sendmsg() Move the existing element-length check before any type-octet inspection so each non-empty element is proven to contain its type byte before the parser looks at data[i + 1]. Fixes: 2bb36870e8cb ("Bluetooth: Unify advertising instance flags check") Reviewed-by: Paul Menzel Signed-off-by: Zhang Cen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- net/bluetooth/mgmt.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index a2bdf25a77aece..040a5595f45fee 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -8721,6 +8721,12 @@ static bool tlv_data_is_valid(struct hci_dev *hdev, u32 adv_flags, u8 *data, if (!cur_len) continue; + /* If the current field length would exceed the total data + * length, then it's invalid. + */ + if (i + cur_len >= len) + return false; + if (data[i + 1] == EIR_FLAGS && (!is_adv_data || flags_managed(adv_flags))) return false; @@ -8737,12 +8743,6 @@ static bool tlv_data_is_valid(struct hci_dev *hdev, u32 adv_flags, u8 *data, if (data[i + 1] == EIR_APPEARANCE && appearance_managed(adv_flags)) return false; - - /* If the current field length would exceed the total data - * length, then it's invalid. - */ - if (i + cur_len >= len) - return false; } return true; -- 2.53.0