net: don't unnecessarily load kernel modules in dev_ioctl()
Starting with v4.16-rc1 we've been seeing a higher than usual number
of requests for the kernel to load networking modules, even on events
which shouldn't trigger a module load (e.g. ioctl(TCGETS)). Stephen
Smalley suggested the problem may lie in commit 44c02a2c3dc5
("dev_ioctl(): move copyin/copyout to callers") which moves changes
the network dev_ioctl() function to always call dev_load(),
regardless of the requested ioctl.
This patch moves the dev_load() calls back into the individual ioctls
while preserving the rest of the original patch.
Reported-by: Dominick Grift <dac.override@gmail.com>
Suggested-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c
index 0ab1af0..a04e1e8 100644
--- a/net/core/dev_ioctl.c
+++ b/net/core/dev_ioctl.c
@@ -402,8 +402,6 @@
if (colon)
*colon = 0;
- dev_load(net, ifr->ifr_name);
-
/*
* See which interface the caller is talking about.
*/
@@ -423,6 +421,7 @@
case SIOCGIFMAP:
case SIOCGIFINDEX:
case SIOCGIFTXQLEN:
+ dev_load(net, ifr->ifr_name);
rcu_read_lock();
ret = dev_ifsioc_locked(net, ifr, cmd);
rcu_read_unlock();
@@ -431,6 +430,7 @@
return ret;
case SIOCETHTOOL:
+ dev_load(net, ifr->ifr_name);
rtnl_lock();
ret = dev_ethtool(net, ifr);
rtnl_unlock();
@@ -447,6 +447,7 @@
case SIOCGMIIPHY:
case SIOCGMIIREG:
case SIOCSIFNAME:
+ dev_load(net, ifr->ifr_name);
if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
return -EPERM;
rtnl_lock();
@@ -494,6 +495,7 @@
/* fall through */
case SIOCBONDSLAVEINFOQUERY:
case SIOCBONDINFOQUERY:
+ dev_load(net, ifr->ifr_name);
rtnl_lock();
ret = dev_ifsioc(net, ifr, cmd);
rtnl_unlock();
@@ -518,6 +520,7 @@
cmd == SIOCGHWTSTAMP ||
(cmd >= SIOCDEVPRIVATE &&
cmd <= SIOCDEVPRIVATE + 15)) {
+ dev_load(net, ifr->ifr_name);
rtnl_lock();
ret = dev_ifsioc(net, ifr, cmd);
rtnl_unlock();