Re: [PATCH] ipv4: fix the rcu race between free_fib_info and ip_route_output_slow

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

On Wed, 2012-05-23 at 07:02 +0200, Eric Dumazet wrote:
> On Wed, 2012-05-23 at 12:54 +0800, Yanmin Zhang wrote:
> > > fi->fib_dev (aka fib_nh[0].nh_dev) need full RCU protection.
> > The new patch posted at does move the
> > resetting to RCU protection.
> Its not enough.
> We must take care that all users are in a RCU protected region.
> They might be already, but a full check is needed.
> For example 
> net/ipv4/fib_trie.c:2563:    fi->fib_dev ? fi->fib_dev->name : "*"
> looks to be safe (because already in a rcu_read_lock())
> But its not.
> Right thing would be to do :
> struct net_device *ndev = rcu_dereference(fi->fib_dev)
> 	...
> 	ndev ? ndev->name : "*"
Thanks for the pointer.

Besides fi->fib_dev here, we need check fi->fib_hash, fi->fib_lhash,
and nexthop_nh->nh_hash.


To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at

[Linux Kernel Discussion]     [Ethernet Bridging]     [Linux Wireless Networking]     [Linux Bluetooth Networking]     [Linux Networking Users]     [VLAN]     [Git]     [IETF Annouce]     [Linux Assembly]     [Security]     [Bugtraq]     [Photo]     [Singles Social Networking]     [Yosemite Information]     [MIPS Linux]     [ARM Linux Kernel]     [ARM Linux]     [Linux Virtualization]     [Linux Security]     [Linux IDE]     [Linux RAID]     [Linux SCSI]     [Free Dating]

Add to Google Powered by Linux