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 C26DC30FA4 for ; Wed, 20 Sep 2023 12:19:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 49E7FC433C8; Wed, 20 Sep 2023 12:19:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1695212388; bh=7fWLhAS9som8UDylbpMYLfO/sU4nHb3GfpgOG//7734=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=M5XXOee3ASLsLQ9q275Dbz9EQjc+UVe4a79o6OX0EdhvK7eF/8bSK8eFrVZpysNQb dUrHrPNebF2resBNTDYGSvq2cWCOqFsgmRNZr163/S/VbSnmnlxnsTL/KMpQJ2WXOZ T/SpIDacoNs2Ax/vJDd0yLBTC/pB31CI/gBHxFis= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zhang Shurong , Hans Verkuil , Sasha Levin Subject: [PATCH 4.19 257/273] media: anysee: fix null-ptr-deref in anysee_master_xfer Date: Wed, 20 Sep 2023 13:31:37 +0200 Message-ID: <20230920112854.216116762@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230920112846.440597133@linuxfoundation.org> References: <20230920112846.440597133@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: Zhang Shurong [ Upstream commit c30411266fd67ea3c02a05c157231654d5a3bdc9 ] In anysee_master_xfer, msg is controlled by user. When msg[i].buf is null and msg[i].len is zero, former checks on msg[i].buf would be passed. Malicious data finally reach anysee_master_xfer. If accessing msg[i].buf[0] without sanity check, null ptr deref would happen. We add check on msg[i].len to prevent crash. Similar commit: commit 0ed554fd769a ("media: dvb-usb: az6027: fix null-ptr-deref in az6027_i2c_xfer()") Signed-off-by: Zhang Shurong Signed-off-by: Hans Verkuil [hverkuil: add spaces around +] Signed-off-by: Sasha Levin --- drivers/media/usb/dvb-usb-v2/anysee.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/usb/dvb-usb-v2/anysee.c b/drivers/media/usb/dvb-usb-v2/anysee.c index 20ee7eea2a91e..83af86505363b 100644 --- a/drivers/media/usb/dvb-usb-v2/anysee.c +++ b/drivers/media/usb/dvb-usb-v2/anysee.c @@ -211,7 +211,7 @@ static int anysee_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, while (i < num) { if (num > i + 1 && (msg[i+1].flags & I2C_M_RD)) { - if (msg[i].len > 2 || msg[i+1].len > 60) { + if (msg[i].len != 2 || msg[i + 1].len > 60) { ret = -EOPNOTSUPP; break; } -- 2.40.1