> James Cammarata a écrit :
> > From: James Cammarata <jimi@sngx.net>
> >
> > Added the ability to write to /proc/net/dev in order to clear the
> > interface counters for a given interface. The ability to zero out
> > counters (especially the error counters) is extremely useful when
> > troubleshooting interface issues. Now diffed against 2.6.25.4, and
> > added some sanity checking.
> >
> Hello James
>
> 1) Every call to get_proc_net() should be paired with a call to
> put_net(), or else you leak struct net.
>
> 2) I am not sure this is the right way to do this... Did you consider to
> extend ethtool instead ?
>
> > Syntax:
> > echo 'net clear-stats ifdev' > /proc/net/dev
> > Where "ifdev" is the device name you wish to clear.
> >
> > This code is based mainly on the code found in drivers/scsi/scsi_proc.c
> >
> > Signed-off-by: James Cammarata <jimi@sngx.net>
> > ---
> >
> > --- linux-2.6.25.4/net/core/dev.c 2008-05-15 10:00:12.000000000
> > -0500
> > +++ linux-2.6.25.4-jcammara/net/core/dev.c 2008-05-16
> > 07:02:48.000000000 -0500
> > @@ -2455,2 +2455,78 @@
> >
> > +/**
> > + * proc_net_dev_write - handle writes to /proc/net/dev
> > + * @file: not used
> > + * @buf: buffer to write
> > + * @length: length of buf, at most PAGE_SIZE
> > + * @ppos: not used
> > + *
> > + * Description: this provides a mechanism to clear statistics on a
> > + * per-interface basis
> > + * "echo 'net clear-stats ifdev' >/proc/net/dev"
> > + * with "ifdev" replaced by the device name you wish to clear.
> > + *
> > + */
> > +static ssize_t proc_net_dev_write(struct file *file, const char
> > __user *buf,
> > + size_t length, loff_t *ppos)
> > +{
> > + char *buffer, *p;
> > + char devname[IFNAMSIZ];
> > + struct net *net;
> > + struct net_device *dev;
> > + int err;
> > +
> > + if (!buf || length > PAGE_SIZE)
> > + return -EINVAL;
> > +
> > + buffer = (char *)__get_free_page(GFP_KERNEL);
> > + if (!buffer)
> > + return -ENOMEM;
> > +
> > + err = -EFAULT;
> > + if (copy_from_user(buffer, buf, length))
> > + goto out;
> > +
> > + err = -EINVAL;
> > + if (length < PAGE_SIZE)
> > + buffer[length] = '__PLACEHOLDER__0_';
> > + else if (buffer[PAGE_SIZE-1])
> > + goto out;
> > +
> > + err = -ENXIO;
> > + net = get_proc_net(file->f_dentry->d_inode);
> > + if (!net)
> > + goto out;
> > +
> > + /*
> > + * Usage: echo "net clear-stats ifdev" >/proc/net/dev
> > + * with "ifdev" replaced by the device name you wish to clear.
> > + */
> > + if (!strncmp("net clear-stats",buffer,15)) {
> > + p = buffer + 16;
> > + if(sscanf(p,"%16s",devname)>0) {
> > + dev = dev_get_by_name(net,devname);
> > + if (dev) {
> > + if (dev->get_stats) {
> > + struct net_device_stats *stats =
> > + dev->get_stats(dev);
> > + memset(stats,0,
> > + sizeof(struct
> > net_device_stats));
> > + }
> > + dev_put(dev);
> > + }
> > + }
> > + }
> > +
> > + /*
> > + * convert success returns so that we return the
> > + * number of bytes consumed.
> > + */
> > + if (!err)
> > + err = length;
> > +
> Here probably, you should add
>
> put_net(net);
>
> > + out:
> > + free_page((unsigned long)buffer);
> > + return err;
> > +}
> > +
> > static void *softnet_seq_start(struct seq_file *seq, loff_t *pos)
> > @@ -2498,2 +2574,3 @@
> > .read = seq_read,
> > + .write = proc_net_dev_write,
> > .llseek = seq_lseek,
> >
> >
>
>
>
>
> --
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