From b9067f5dc4a07c8e24e01a1b277c6722d91be39e Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 27 Jul 2021 15:44:47 +0200 Subject: net: split out SIOCDEVPRIVATE handling from dev_ioctl SIOCDEVPRIVATE ioctl commands are mainly used in really old drivers, and they have a number of problems: - They hide behind the normal .ndo_do_ioctl function that is also used for other things in modern drivers, so it's hard to spot a driver that actually uses one of these - Since drivers use a number different calling conventions, it is impossible to support compat mode for them in a generic way. - With all drivers using the same 16 commands codes, there is no way to introspect the data being passed through things like strace. Add a new net_device_ops callback pointer, to address the first two of these. Separating them from .ndo_do_ioctl makes it easy to grep for drivers with a .ndo_siocdevprivate callback, and the unwieldy name hopefully makes it easier to spot in code review. By passing the ifreq structure and the ifr_data pointer separately, it is no longer necessary to overload these, and the driver can use either one for a given command. Cc: Cong Wang Signed-off-by: Arnd Bergmann Signed-off-by: David S. Miller --- net/core/dev_ioctl.c | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) (limited to 'net') diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c index 950e2fe5d56a..75e3e340d884 100644 --- a/net/core/dev_ioctl.c +++ b/net/core/dev_ioctl.c @@ -259,6 +259,23 @@ static int dev_do_ioctl(struct net_device *dev, return err; } +static int dev_siocdevprivate(struct net_device *dev, + struct ifreq *ifr, unsigned int cmd) +{ + const struct net_device_ops *ops = dev->netdev_ops; + void __user *data = ifr->ifr_data; + + if (ops->ndo_siocdevprivate) { + if (netif_device_present(dev)) + return ops->ndo_siocdevprivate(dev, ifr, data, cmd); + else + return -ENODEV; + } + + /* fall back to do_ioctl for drivers not yet converted */ + return dev_do_ioctl(dev, ifr, cmd); +} + /* * Perform the SIOCxIFxxx calls, inside rtnl_lock() */ @@ -336,9 +353,11 @@ static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd) * Unknown or private ioctl */ default: - if ((cmd >= SIOCDEVPRIVATE && - cmd <= SIOCDEVPRIVATE + 15) || - cmd == SIOCBONDENSLAVE || + if (cmd >= SIOCDEVPRIVATE && + cmd <= SIOCDEVPRIVATE + 15) + return dev_siocdevprivate(dev, ifr, cmd); + + if (cmd == SIOCBONDENSLAVE || cmd == SIOCBONDRELEASE || cmd == SIOCBONDSETHWADDR || cmd == SIOCBONDSLAVEINFOQUERY || -- cgit v1.2.3-58-ga151