linux.git/net/sched, branch v4.12

net: sched: Fix one possible panic when no destroy callback

2017-06-29T16:55:12+00:00

When qdisc fail to init, qdisc_create would invoke the destroy callback
to cleanup. But there is no check if the callback exists really. So it
would cause the panic if there is no real destroy callback like the qdisc
codel, fq, and so on.

Take codel as an example following:
When a malicious user constructs one invalid netlink msg, it would cause
codel_init->codel_change->nla_parse_nested failed.
Then kernel would invoke the destroy callback directly but qdisc codel
doesn't define one. It causes one panic as a result.

Now add one the check for destroy to avoid the possible panic.

Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation")
Signed-off-by: Gao Feng 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller

net/act_pedit: fix an error code

2017-06-14T19:24:18+00:00

I'm reviewing static checker warnings where we do ERR_PTR(0), which is
the same as NULL.  I'm pretty sure we intended to return ERR_PTR(-EINVAL)
here.  Sometimes these bugs lead to a NULL dereference but I don't
immediately see that problem here.

Fixes: 71d0ed7079df ("net/act_pedit: Support using offset relative to the conventional network headers")
Signed-off-by: Dan Carpenter 
Acked-by: Amir Vadai 
Signed-off-by: David S. Miller

net_sched: move tcf_lock down after gen_replace_estimator()

2017-06-14T18:39:19+00:00

Laura reported a sleep-in-atomic kernel warning inside
tcf_act_police_init() which calls gen_replace_estimator() with
spinlock protection.

It is not necessary in this case, we already have RTNL lock here
so it is enough to protect concurrent writers. For the reader,
i.e. tcf_act_police(), it needs to make decision based on this
rate estimator, in the worst case we drop more/less packets than
necessary while changing the rate in parallel, it is still acceptable.

Reported-by: Laura Abbott 
Reported-by: Nick Huber 
Cc: Jamal Hadi Salim 
Signed-off-by: Cong Wang 
Acked-by: Jamal Hadi Salim 
Signed-off-by: David S. Miller

net: sched: cls_matchall: fix null pointer dereference

2017-05-22T18:54:16+00:00

Since the head is guaranteed by the check above to be null, the call_rcu
would explode. Remove the previously logically dead code that was made
logically very much alive and kicking.

Fixes: 985538eee06f ("net/sched: remove redundant null check on head")
Signed-off-by: Jiri Pirko 
Signed-off-by: David S. Miller

net: sched: optimize class dumps

2017-05-12T01:37:40+00:00

In commit 59cc1f61f09c ("net: sched: convert qdisc linked list to
hashtable") we missed the opportunity to considerably speed up
tc_dump_tclass_root() if a qdisc handle is provided by user.

Instead of iterating all the qdiscs, use qdisc_match_from_root()
to directly get the one we look for.

Signed-off-by: Eric Dumazet 
Cc: Jiri Kosina 
Cc: Jamal Hadi Salim 
Cc: Cong Wang 
Cc: Jiri Pirko 
Signed-off-by: David S. Miller

net: use kvmalloc with __GFP_REPEAT rather than open coded variant

2017-05-09T00:15:13+00:00

fq_alloc_node, alloc_netdev_mqs and netif_alloc* open code kmalloc with
vmalloc fallback.  Use the kvmalloc variant instead.  Keep the
__GFP_REPEAT flag based on explanation from Eric:

 "At the time, tests on the hardware I had in my labs showed that
  vmalloc() could deliver pages spread all over the memory and that was
  a small penalty (once memory is fragmented enough, not at boot time)"

The way how the code is constructed means, however, that we prefer to go
and hit the OOM killer before we fall back to the vmalloc for requests
<=32kB (with 4kB pages) in the current code.  This is rather disruptive
for something that can be achived with the fallback.  On the other hand
__GFP_REPEAT doesn't have any useful semantic for these requests.  So
the effect of this patch is that requests which fit into 32kB will fall
back to vmalloc easier now.

Link: http://lkml.kernel.org/r/20170306103327.2766-3-mhocko@kernel.org
Signed-off-by: Michal Hocko 
Acked-by: Vlastimil Babka 
Cc: Eric Dumazet 
Cc: David Miller 
Cc: Shakeel Butt 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

treewide: use kv[mz]alloc* rather than opencoded variants

2017-05-09T00:15:13+00:00

There are many code paths opencoding kvmalloc.  Let's use the helper
instead.  The main difference to kvmalloc is that those users are
usually not considering all the aspects of the memory allocator.  E.g.
allocation requests <= 32kB (with 4kB pages) are basically never failing
and invoke OOM killer to satisfy the allocation.  This sounds too
disruptive for something that has a reasonable fallback - the vmalloc.
On the other hand those requests might fallback to vmalloc even when the
memory allocator would succeed after several more reclaim/compaction
attempts previously.  There is no guarantee something like that happens
though.

This patch converts many of those places to kv[mz]alloc* helpers because
they are more conservative.

Link: http://lkml.kernel.org/r/20170306103327.2766-2-mhocko@kernel.org
Signed-off-by: Michal Hocko 
Reviewed-by: Boris Ostrovsky  # Xen bits
Acked-by: Kees Cook 
Acked-by: Vlastimil Babka 
Acked-by: Andreas Dilger  # Lustre
Acked-by: Christian Borntraeger  # KVM/s390
Acked-by: Dan Williams  # nvdim
Acked-by: David Sterba  # btrfs
Acked-by: Ilya Dryomov  # Ceph
Acked-by: Tariq Toukan  # mlx4
Acked-by: Leon Romanovsky  # mlx5
Cc: Martin Schwidefsky 
Cc: Heiko Carstens 
Cc: Herbert Xu 
Cc: Anton Vorontsov 
Cc: Colin Cross 
Cc: Tony Luck 
Cc: "Rafael J. Wysocki" 
Cc: Ben Skeggs 
Cc: Kent Overstreet 
Cc: Santosh Raspatur 
Cc: Hariprasad S 
Cc: Yishai Hadas 
Cc: Oleg Drokin 
Cc: "Yan, Zheng" 
Cc: Alexander Viro 
Cc: Alexei Starovoitov 
Cc: Eric Dumazet 
Cc: David Miller 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

net/sched: remove redundant null check on head

2017-05-04T15:01:30+00:00

head is previously null checked and so the 2nd null check on head
is redundant and therefore can be removed.

Detected by CoverityScan, CID#1399505 ("Logically dead code")

Signed-off-by: Colin Ian King 
Acked-by: Jiri Pirko 
Signed-off-by: David S. Miller

net: sched: add helpers to handle extended actions

2017-05-02T19:33:54+00:00

Jump is now the only one using value action opcode. This is going to
change soon. So introduce helpers to work with this. Convert TC_ACT_JUMP.

This also fixes the TC_ACT_JUMP check, which is incorrectly done as a
bit check, not a value check.

Fixes: e0ee84ded796 ("net sched actions: Complete the JUMPX opcode")
Signed-off-by: Jiri Pirko 
Acked-by: Jamal Hadi Salim 
Signed-off-by: David S. Miller

flower: check unused bits in MPLS fields

2017-05-01T15:12:21+00:00

Since several of the the netlink attributes used to configure the flower
classifier's MPLS TC, BOS and Label fields have additional bits which are
unused, check those bits to ensure that they are actually 0 as suggested
by Jamal.

Signed-off-by: Benjamin LaHaise 
Cc: David Miller 
Cc: Jamal Hadi Salim 
Cc: Simon Horman 
Cc: Jakub Kicinski 
Cc: Jiri Pirko 
Signed-off-by: David S. Miller