From: Lee Jones Subject: [PATCH 2/6] hwrng: core: Simplify RNG switching from sysfs Date: Fri, 11 Sep 2015 21:08:26 +0100 Message-ID: <1442002110-28733-3-git-send-email-lee.jones@linaro.org> References: <1442002110-28733-1-git-send-email-lee.jones@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: devicetree@vger.kernel.org, herbert@gondor.apana.org.au, linux-crypto@vger.kernel.org, mpm@selenic.com, Lee Jones , kernel@stlinux.com To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Return-path: In-Reply-To: <1442002110-28733-1-git-send-email-lee.jones@linaro.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org List-Id: linux-crypto.vger.kernel.org If we attempt to use sysfs to change the current RNG in the usual way i.e. issuing something like: `echo 8a8a000.rng > /sys/devices/virtual/misc/hw_random/rng_current` ... it will fail because the code doesn't currently take the '\n' into consideration. Well, now it does. Signed-off-by: Lee Jones --- drivers/char/hw_random/core.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index da8faf7..14dc984 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -316,6 +316,7 @@ static ssize_t hwrng_attr_current_store(struct device *dev, const char *buf, size_t len) { int err; + int snip = 0; struct hwrng *rng; err = mutex_lock_interruptible(&rng_mutex); @@ -323,7 +324,11 @@ static ssize_t hwrng_attr_current_store(struct device *dev, return -ERESTARTSYS; err = -ENODEV; list_for_each_entry(rng, &rng_list, list) { - if (strcmp(rng->name, buf) == 0) { + + if (buf[len-1] == '\n') + snip = 1; /* Snip one character */ + + if (strncmp(rng->name, buf, len - snip) == 0) { err = 0; if (rng != current_rng) err = set_current_rng(rng); -- 1.9.1