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  1. 30 Dec, 2016 2 commits
  3. 29 Dec, 2016 10 commits
  5. 28 Dec, 2016 18 commits
  7. 27 Dec, 2016 7 commits
  9. 26 Dec, 2016 3 commits
    • Al Viro's avatar
      arm64: don't pull uaccess.h into *.S · b4b8664d
      Al Viro authored 
      Split asm-only parts of arm64 uaccess.h into a new header and use that
from *.S.
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      b4b8664d
    • Florian Fainelli's avatar
      net: korina: Fix NAPI versus resources freeing · e6afb1ad
      Florian Fainelli authored 
      Commit beb0babf ("korina: disable napi on close and restart")
introduced calls to napi_disable() that were missing before,
unfortunately this leaves a small window during which NAPI has a chance
to run, yet we just freed resources since korina_free_ring() has been
called:

Fix this by disabling NAPI first then freeing resource, and make sure
that we also cancel the restart task before doing the resource freeing.

Fixes: beb0babf ("korina: disable napi on close and restart")
Reported-by: default avatarAlexandros C. Couloumbis <alex@ozo.com>
Signed-off-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e6afb1ad
    • Daniel Borkmann's avatar
      net, sched: fix soft lockup in tc_classify · 628185cf
      Daniel Borkmann authored 
      Shahar reported a soft lockup in tc_classify(), where we run into an
endless loop when walking the classifier chain due to tp->next == tp
which is a state we should never run into. The issue only seems to
trigger under load in the tc control path.

What happens is that in tc_ctl_tfilter(), thread A allocates a new
tp, initializes it, sets tp_created to 1, and calls into tp->ops->change()
with it. In that classifier callback we had to unlock/lock the rtnl
mutex and returned with -EAGAIN. One reason why we need to drop there
is, for example, that we need to request an action module to be loaded.

This happens via tcf_exts_validate() -> tcf_action_init/_1() meaning
after we loaded and found the requested action, we need to redo the
whole request so we don't race against others. While we had to unlock
rtnl in that time, thread B's request was processed next on that CPU.
Thread B added a new tp instance successfully to the classifier chain.
When thread A returned grabbing the rtnl mutex again, propagating -EAGAIN
and destroying its tp instance which never got linked, we goto replay
and redo A's request.

This time when walking the classifier chain in tc_ctl_tfilter() for
checking for existing tp instances we had a priority match and found
the tp instance that was created and linked by thread B. Now calling
again into tp->ops->change() with that tp was successful and returned
without error.

tp_created was never cleared in the second round, thus kernel thinks
that we need to link it into the classifier chain (once again). tp and
*back point to the same object due to the match we had earlier on. Thus
for thread B's already public tp, we reset tp->next to tp itself and
link it into the chain, which eventually causes the mentioned endless
loop in tc_classify() once a packet hits the data path.

Fix is to clear tp_created at the beginning of each request, also when
we replay it. On the paths that can cause -EAGAIN we already destroy
the original tp instance we had and on replay we really need to start
from scratch. It seems that this issue was first introduced in commit
12186be7 ("net_cls: fix unconfigured struct tcf_proto keeps chaining
and avoid kernel panic when we use cls_cgroup").

Fixes: 12186be7 ("net_cls: fix unconfigured struct tcf_proto keeps chaining and avoid kernel panic when we use cls_cgroup")
Reported-by: default avatarShahar Klein <shahark@mellanox.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: default avatarEric Dumazet <edumazet@google.com>
Tested-by: default avatarShahar Klein <shahark@mellanox.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      628185cf
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