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 6D10251121D; Wed, 30 Sep 2026 16:43:51 +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=1790786632; cv=none; b=qgPuAxZPeFwWpmGsD3eGn579M9xb87tcHhNPZg7kgmuiNZIk1ItJYj754UlMSow0xZPNqrqToVPvSB9IPeLlLckGUQNCe1G0CS3LBmZPNFH+/EyUE0KEFd34G3F1I2Xke+CEGHQlNKfoQ1Za+aw3ZuDqvU3/ACqd1gN9mpebgGU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790786632; c=relaxed/simple; bh=IF+komBU9PxrBkd5p0AyZAeKR3oAVm1F7dgtOdPrIMc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=aJ4hwrnT4px7TNx6VZOO5FiY2mCkZJ1eW5a8y5S+JWAfPmaOG1gZ0DDsg5l677u2Ba9uB9HCmtRFfyhboiwnWXKzVF36EWtqqLcwei4jIz5tIse2MK37BkK3j5BK8a0aQZ5aZk/V5+xEL9y82z2fgWwEbjuaDW5fjYSvCwzbut8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=MGss5sHY; 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="MGss5sHY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5822D1F00898; Wed, 30 Sep 2026 16:43:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790786630; bh=cVEdzHV1lOWDcs4lM/5QJE9a+1YYjoYaBoWfdHEygss=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=MGss5sHYq0uKHjPpOGMVCAnRTUaHVhMXrZb7DLwW7W6kydHh+5hsf+7BstizzBJ/i CexDUGsfapTx9u8+znSdElgCFy8hDKHrwwmSspW4RGTWItaMrJsf52yEsy7TAythEh cH+hVlzxOg2loX36BlqzNc0I99HqINNjKXg8i5qs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?=C3=96mer=20Mete=20Kaya?= , David Heidelberg , Sasha Levin Subject: [PATCH 6.1 885/982] nfc: llcp: fix WKS SAP hijacking via prefix match in nfc_llcp_wks_sap() Date: Wed, 30 Sep 2026 17:27:01 +0200 Message-ID: <20260930152435.757396611@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152416.775402466@linuxfoundation.org> References: <20260930152416.775402466@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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ömer Mete Kaya [ Upstream commit 408cff6bd60636df201274d320edfdfde9ed41db ] nfc_llcp_wks_sap() compares only service_name_len bytes, so a short service_name like "u" matches longer WKS strings like "urn:nfc:sn:snep". Fix by requiring exact length match before strncmp(). Fixes: d646960f7986 ("NFC: Initial LLCP support") Signed-off-by: Ömer Mete Kaya Link: https://patch.msgid.link/20260909121437.33744-1-omermetekaya0@gmail.com Signed-off-by: David Heidelberg Signed-off-by: Sasha Levin --- net/nfc/llcp_core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/nfc/llcp_core.c b/net/nfc/llcp_core.c index a4d7b2eaebd43..0b1a2755f58ac 100644 --- a/net/nfc/llcp_core.c +++ b/net/nfc/llcp_core.c @@ -367,7 +367,8 @@ static int nfc_llcp_wks_sap(const char *service_name, size_t service_name_len) if (wks[sap] == NULL) continue; - if (strncmp(wks[sap], service_name, service_name_len) == 0) + if (strlen(wks[sap]) == service_name_len && + !strncmp(wks[sap], service_name, service_name_len)) return sap; } -- 2.53.0