From patchwork Wed Dec 13 13:22:43 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Carpenter X-Patchwork-Id: 13491009 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="Oq6YiaXY" Received: from mail-wm1-x329.google.com (mail-wm1-x329.google.com [IPv6:2a00:1450:4864:20::329]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AE814F2 for ; Wed, 13 Dec 2023 05:22:48 -0800 (PST) Received: by mail-wm1-x329.google.com with SMTP id 5b1f17b1804b1-40c25973988so70627295e9.2 for ; Wed, 13 Dec 2023 05:22:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1702473767; x=1703078567; darn=vger.kernel.org; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :from:to:cc:subject:date:message-id:reply-to; bh=jY13RsvR2p7nAVWn/STfQAiQyGaFoi3utwqqvjImNyk=; b=Oq6YiaXYzOaamZEp7gALMU85D8UlkkbjER2evO96CvFXabDs7pnBOtC4HMvZK7JnKp Ok4KU4DDUffyyGaRepYKa+gAz8W0F4WJAuH5EGKxhgFrQKKi1a3CjqENOjAAf1+J7XlP MvnQG6FQgwwTXU/+YPaOVI78XfrMcmsAP5WI4WkIE5yhIa0udduEEikW7NiflFe8+sGi 3h5JsJApeit2VNth/gMlSUQXyuT6Q5+ugNXZe1AagCvnTFVlRC0jyCLwf/NhtqHrvcoe qvUdPOesNmJlCjBn834dDD7vnjp+MIWYUJ3Aa5wAepn6lMVfy/ei2rnx2jks92FzHxXh h7iQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702473767; x=1703078567; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=jY13RsvR2p7nAVWn/STfQAiQyGaFoi3utwqqvjImNyk=; b=MtqoBrScMUGCWeLAFu+RvJkdFXOBbwcZUsYsnHbSK/zfvc0ck62nGeTRG82+LL+ajE 73ICDq1WIJggrWACWjzurnmmCpJ8QmZaY/gcx0tJhKvka3e1teKdQ2+epQUSk0/1+XZG jedEcHG6MAhUwNsIcF+q2Y2bB6VR5v698xYdRIu5qxMpOgyAF5UDWC8Mwq4WTSSKehVY 3HKnHt9jgSKxR0nrJlTaxhJvY8DK3034FLrtYvtq2iEh5Zmkmk6RfFnRmMPaIMcbGId1 qqQN02zYzEkmpCT7dToQcKv5WliBATFteXjx71ACqxscnDmAnCxrx/5oSQkI2Iru2my0 J72g== X-Gm-Message-State: AOJu0Yyr8rmlJOAK6V3/HXm0wyC958m5z9/WFv2KuNC6izbeirPGA1iK 0wb2SwukUN28vALGk6tqc+88jg== X-Google-Smtp-Source: AGHT+IFNIB8ZVVFyMT1ctnUHjs97JWr+gn9ZrulTqN7ITxPsUO3rpI/TAHzPGq9CbL5OwD8wPmSpAw== X-Received: by 2002:a05:600c:3556:b0:40b:4c54:3d78 with SMTP id i22-20020a05600c355600b0040b4c543d78mr3882194wmq.28.1702473767093; Wed, 13 Dec 2023 05:22:47 -0800 (PST) Received: from localhost ([102.140.209.237]) by smtp.gmail.com with ESMTPSA id s5-20020a05600c384500b0040b632f31d2sm20693616wmr.5.2023.12.13.05.22.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 13 Dec 2023 05:22:46 -0800 (PST) Date: Wed, 13 Dec 2023 16:22:43 +0300 From: Dan Carpenter To: Linus Walleij , Lee Jones Cc: Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH v2] usb: fotg210-hcd: delete an incorrect bounds test Message-ID: Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline Here "temp" is the number of characters that we have written and "size" is the size of the buffer. The intent was clearly to say that if we have written to the end of the buffer then stop. However, for that to work the comparison should have been done on the original "size" value instead of the "size -= temp" value. Not only will that not trigger when we want to, but there is a small chance that it will trigger incorrectly before we want it to and we break from the loop slightly earlier than intended. This code was recently changed from using snprintf() to scnprintf(). With snprintf() we likely would have continued looping and passed a negative size parameter to snprintf(). This would have triggered an annoying WARN(). Now that we have converted to scnprintf() "size" will never drop below 1 and there is no real need for this test. We could change the condition to "if (temp <= 1) goto done;" but just deleting the test is cleanest. Fixes: 7d50195f6c50 ("usb: host: Faraday fotg210-hcd driver") Signed-off-by: Dan Carpenter Reviewed-by: Linus Walleij Reviewed-by: Lee Jones --- v2: Use the correct Fixes tag. Add Reviewed-by tags. drivers/usb/fotg210/fotg210-hcd.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/usb/fotg210/fotg210-hcd.c b/drivers/usb/fotg210/fotg210-hcd.c index b2f8b53cc8ef..8c5aaf860635 100644 --- a/drivers/usb/fotg210/fotg210-hcd.c +++ b/drivers/usb/fotg210/fotg210-hcd.c @@ -426,8 +426,6 @@ static void qh_lines(struct fotg210_hcd *fotg210, struct fotg210_qh *qh, td->urb); size -= temp; next += temp; - if (temp == size) - goto done; } temp = scnprintf(next, size, "\n"); @@ -435,7 +433,6 @@ static void qh_lines(struct fotg210_hcd *fotg210, struct fotg210_qh *qh, size -= temp; next += temp; -done: *sizep = size; *nextp = next; }