linux-toradex.git/net/core, branch v3.2.13

neighbour: Fixed race condition at tbl->nht

2012-03-19T16:02:21+00:00

[ Upstream commit 84338a6c9dbb6ff3de4749864020f8f25d86fc81 ]

When the fixed race condition happens:

1. While function neigh_periodic_work scans the neighbor hash table
pointed by field tbl->nht, it unlocks and locks tbl->lock between
buckets in order to call cond_resched.

2. Assume that function neigh_periodic_work calls cond_resched, that is,
the lock tbl->lock is available, and function neigh_hash_grow runs.

3. Once function neigh_hash_grow finishes, and RCU calls
neigh_hash_free_rcu, the original struct neigh_hash_table that function
neigh_periodic_work was using doesn't exist anymore.

4. Once back at neigh_periodic_work, whenever the old struct
neigh_hash_table is accessed, things can go badly.

Signed-off-by: Michel Machado 
CC: "David S. Miller" 
CC: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

gro: more generic L2 header check

2012-03-01T00:31:04+00:00

[ Upstream commit 5ca3b72c5da47d95b83857b768def6172fbc080a ]

Shlomo Pongratz reported GRO L2 header check was suited for Ethernet
only, and failed on IB/ipoib traffic.

He provided a patch faking a zeroed header to let GRO aggregates frames.

Roland Dreier, Herbert Xu, and others suggested we change GRO L2 header
check to be more generic, ie not assuming L2 header is 14 bytes, but
taking into account hard_header_len.

__napi_gro_receive() has special handling for the common case (Ethernet)
to avoid a memcmp() call and use an inline optimized function instead.

Signed-off-by: Eric Dumazet 
Reported-by: Shlomo Pongratz 
Cc: Roland Dreier 
Cc: Or Gerlitz 
Cc: Herbert Xu 
Tested-by: Sean Hefty 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

netpoll: netpoll_poll_dev() should access dev->flags

2012-03-01T00:30:58+00:00

[ Upstream commit 58e05f357a039a94aa36475f8c110256f693a239 ]

commit 5a698af53f (bond: service netpoll arp queue on master device)
tested IFF_SLAVE flag against dev->priv_flags instead of dev->flags

Signed-off-by: Eric Dumazet 
Cc: WANG Cong 
Acked-by: Neil Horman 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: reintroduce missing rcu_assign_pointer() calls

2012-02-03T17:22:20+00:00

[ Upstream commit cf778b00e96df6d64f8e21b8395d1f8a859ecdc7 ]

commit a9b3cd7f32 (rcu: convert uses of rcu_assign_pointer(x, NULL) to
RCU_INIT_POINTER) did a lot of incorrect changes, since it did a
complete conversion of rcu_assign_pointer(x, y) to RCU_INIT_POINTER(x,
y).

We miss needed barriers, even on x86, when y is not NULL.

Signed-off-by: Eric Dumazet 
CC: Stephen Hemminger 
CC: Paul E. McKenney 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

netns: fix net_alloc_generic()

2012-02-03T17:22:17+00:00

[ Upstream commit 073862ba5d249c20bd5c49fc6d904ff0e1f6a672 ]

When a new net namespace is created, we should attach to it a "struct
net_generic" with enough slots (even empty), or we can hit the following
BUG_ON() :

[  200.752016] kernel BUG at include/net/netns/generic.h:40!
...
[  200.752016]  [] ? get_cfcnfg+0x3a/0x180
[  200.752016]  [] ? lockdep_rtnl_is_held+0x10/0x20
[  200.752016]  [] caif_device_notify+0x2e/0x530
[  200.752016]  [] notifier_call_chain+0x67/0x110
[  200.752016]  [] raw_notifier_call_chain+0x11/0x20
[  200.752016]  [] call_netdevice_notifiers+0x32/0x60
[  200.752016]  [] register_netdevice+0x196/0x300
[  200.752016]  [] register_netdev+0x19/0x30
[  200.752016]  [] loopback_net_init+0x4a/0xa0
[  200.752016]  [] ops_init+0x42/0x180
[  200.752016]  [] setup_net+0x6b/0x100
[  200.752016]  [] copy_net_ns+0x86/0x110
[  200.752016]  [] create_new_namespaces+0xd9/0x190

net_alloc_generic() should take into account the maximum index into the
ptr array, as a subsystem might use net_generic() anytime.

This also reduces number of reallocations in net_assign_generic()

Reported-by: Sasha Levin 
Tested-by: Sasha Levin 
Signed-off-by: Eric Dumazet 
Cc: Sjur Brændeland 
Cc: Eric W. Biederman 
Cc: Pavel Emelyanov 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: relax rcvbuf limits

2011-12-23T07:15:14+00:00

skb->truesize might be big even for a small packet.

Its even bigger after commit 87fb4b7b533 (net: more accurate skb
truesize) and big MTU.

We should allow queueing at least one packet per receiver, even with a
low RCVBUF setting.

Reported-by: Michal Simek 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

rps: fix insufficient bounds checking in store_rps_dev_flow_table_cnt()

2011-12-23T03:34:56+00:00

Setting a large rps_flow_cnt like (1 << 30) on 32-bit platform will
cause a kernel oops due to insufficient bounds checking.

	if (count > 1<<30) {
		/* Enforce a limit to prevent overflow */
		return -EINVAL;
	}
	count = roundup_pow_of_two(count);
	table = vmalloc(RPS_DEV_FLOW_TABLE_SIZE(count));

Note that the macro RPS_DEV_FLOW_TABLE_SIZE(count) is defined as:

	... + (count * sizeof(struct rps_dev_flow))

where sizeof(struct rps_dev_flow) is 8.  (1 << 30) * 8 will overflow
32 bits.

This patch replaces the magic number (1 << 30) with a symbolic bound.

Suggested-by: Eric Dumazet 
Signed-off-by: Xi Wang 
Signed-off-by: David S. Miller

net: Add a flow_cache_flush_deferred function

2011-12-21T21:48:08+00:00

flow_cach_flush() might sleep but can be called from
atomic context via the xfrm garbage collector. So add
a flow_cache_flush_deferred() function and use this if
the xfrm garbage colector is invoked from within the
packet path.

Signed-off-by: Steffen Klassert 
Acked-by: Timo Teräs 
Signed-off-by: David S. Miller

net: Silence seq_scale() unused warning

2011-12-06T18:59:16+00:00

On a CONFIG_NET=y build

net/core/secure_seq.c:22: warning: 'seq_scale' defined but not
used

Signed-off-by: Stephen Boyd 
Signed-off-by: David S. Miller

ipv4:correct description for tcp_max_syn_backlog

2011-12-06T18:02:28+00:00

Since commit c5ed63d66f24(tcp: fix three tcp sysctls tuning),
sysctl_max_syn_backlog is determined by tcp_hashinfo->ehash_mask,
and the minimal value is 128, and it will increase in proportion to the
memory of machine.
The original description for tcp_max_syn_backlog and sysctl_max_syn_backlog
are out of date.

Changelog:
V2: update description for sysctl_max_syn_backlog

Signed-off-by: Weiping Pan 
Reviewed-by: Shan Wei 
Acked-by: Neil Horman 
Signed-off-by: David S. Miller