From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: [PATCH net-next 2/2] sysctl: range checking in do_proc_dointvec_ms_jiffies_conv Date: Wed, 24 Jul 2013 18:35:22 +0400 Message-ID: <51EFE62A.70901@cogentembedded.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: davem@davemloft.net, netdev@vger.kernel.org, Andrew Morton , linux-kernel@vger.kernel.org To: Francesco Fusco Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Hello. On 24-07-2013 12:39, Francesco Fusco wrote: > When (integer) sysctl values are expressed in ms and have to be > represented internally as jiffies. The msecs_to_jiffies function > returns an unsigned long, which gets assigned to the integer. > This patch prevents the value to be assigned if bigger than > INT_MAX, done in a similar way as in cba9f3 ("Range checking in > do_proc_dointvec_(userhz_)jiffies_conv"). > Signed-off-by: Francesco Fusco > CC: Andrew Morton > CC: linux-kernel@vger.kernel.org > --- > kernel/sysctl.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > diff --git a/kernel/sysctl.c b/kernel/sysctl.c > index ac09d98..00813e5 100644 > --- a/kernel/sysctl.c > +++ b/kernel/sysctl.c > @@ -2346,7 +2346,11 @@ static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp, > int write, void *data) > { > if (write) { > - *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp); > + unsigned long jif = 0; Pointless initializer. And an empty line wouldn't hurt after declaration. > + jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp); One space after = is enough. > + if (jif > INT_MAX) > + return 1; > + *valp = (int)jif; WBR, Sergei