From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 206F6CA40; Tue, 16 Jul 2024 15:37:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721144242; cv=none; b=SUaJs7cofRy8ayXKtLLZYIiT2gBGtaKxp4prSB/kOcJ5EsEhUoBGOnU2PV32eLRrRyFbd60BViWYnQXap/OHVhNNV6RrmOigZ7ioXikMYswnqfDxoZEsA1kSai2MDzK+yI4sNjA3ibTeo7lK2NYyfc59maoK+sesvXxLyvK/LEU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721144242; c=relaxed/simple; bh=yUf4dKOAOERMPOO6oUAjQbPYjATNIMhVlShgRYXixXo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WBHzC+3BPceBaD1JzjQRVusJyVfG3eASIx7haiJgAEWTRTnmsWZwd0T3KOgOFGk1daS3tql50DBMYWGn8DhPGh7ITCuYeGnO1DmcOHw1f7DzhvbYZHMU9kZW+20+K8hkEFPGo7ETPZMYHtQ9tLC7DT2nrs5tqAqCiZqljvaHVKg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=iWDJtj4S; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="iWDJtj4S" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 96EE6C116B1; Tue, 16 Jul 2024 15:37:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1721144242; bh=yUf4dKOAOERMPOO6oUAjQbPYjATNIMhVlShgRYXixXo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iWDJtj4SBEy9LFMnDB0YSdNp/HSjj7ySq7u8MLxHT4xiut3gmOEyJDrgUbCmDQY0N OjV13FbIPXolYNAfzT3HDHudejpCMX/8H9dR5DJEOOH87ja2b4hRugvMxzkBexl0pa myWcOWW0dWQOSE7cDMeV5U7IIHY3C/7zZ96wl7Ck= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Lee Jones , stable Subject: [PATCH 4.19 56/66] usb: gadget: configfs: Prevent OOB read/write in usb_string_copy() Date: Tue, 16 Jul 2024 17:31:31 +0200 Message-ID: <20240716152740.301483416@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240716152738.161055634@linuxfoundation.org> References: <20240716152738.161055634@linuxfoundation.org> User-Agent: quilt/0.67 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 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lee Jones commit 6d3c721e686ea6c59e18289b400cc95c76e927e0 upstream. Userspace provided string 's' could trivially have the length zero. Left unchecked this will firstly result in an OOB read in the form `if (str[0 - 1] == '\n') followed closely by an OOB write in the form `str[0 - 1] = '\0'`. There is already a validating check to catch strings that are too long. Let's supply an additional check for invalid strings that are too short. Signed-off-by: Lee Jones Cc: stable Link: https://lore.kernel.org/r/20240705074339.633717-1-lee@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/configfs.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/usb/gadget/configfs.c +++ b/drivers/usb/gadget/configfs.c @@ -116,9 +116,12 @@ static int usb_string_copy(const char *s int ret; char *str; char *copy = *s_copy; + ret = strlen(s); if (ret > USB_MAX_STRING_LEN) return -EOVERFLOW; + if (ret < 1) + return -EINVAL; if (copy) { str = copy;