Messages in this thread | | | Date | Sat, 11 Oct 2014 19:11:22 -0700 | From | Guenter Roeck <> | Subject | Re: [PATCH] char: hw_random: core.c: Changed from using strncpy to strlcpy |
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On Sat, Oct 11, 2014 at 05:27:41PM -0700, Mark D Rustad wrote: > On Oct 11, 2014, at 3:36 PM, Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se> wrote: > > > Changed from using strncpy to strlcpy to simplify the code > > Actually you changed from using strncat to strlcat. > ... and changed the length parameter along the way, making the length check overall quite worthless and introducing a _real_ problem.
Guenter
> > Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se> > > --- > > drivers/char/hw_random/core.c | 12 ++++-------- > > 1 file changed, 4 insertions(+), 8 deletions(-) > > > > diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c > > index aa30a25..1500cfd 100644 > > --- a/drivers/char/hw_random/core.c > > +++ b/drivers/char/hw_random/core.c > > @@ -281,7 +281,6 @@ static ssize_t hwrng_attr_available_show(struct device *dev, > > char *buf) > > { > > int err; > > - ssize_t ret = 0; > > struct hwrng *rng; > > > > err = mutex_lock_interruptible(&rng_mutex); > > @@ -289,16 +288,13 @@ static ssize_t hwrng_attr_available_show(struct device *dev, > > return -ERESTARTSYS; > > buf[0] = '\0'; > > list_for_each_entry(rng, &rng_list, list) { > > - strncat(buf, rng->name, PAGE_SIZE - ret - 1); > > - ret += strlen(rng->name); > > - strncat(buf, " ", PAGE_SIZE - ret - 1); > > - ret++; > > + strlcat(buf, rng->name, PAGE_SIZE); > > + strlcat(buf, " ", PAGE_SIZE); > > } > > - strncat(buf, "\n", PAGE_SIZE - ret - 1); > > - ret++; > > + strlcat(buf, "\n", PAGE_SIZE); > > mutex_unlock(&rng_mutex); > > > > - return ret; > > + return strlen(buf); > > } > > > > static DEVICE_ATTR(rng_current, S_IRUGO | S_IWUSR, > > -- > > 1.7.10.4 > > -- > Mark Rustad, MRustad@gmail.com >
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