linux-stable.git/net, branch v4.4.237

SUNRPC: stop printk reading past end of string

2020-09-23T06:44:26+00:00

[ Upstream commit 8c6b6c793ed32b8f9770ebcdf1ba99af423c303b ]

Since p points at raw xdr data, there's no guarantee that it's NULL
terminated, so we should give a length.  And probably escape any special
characters too.

Reported-by: Zhi Li 
Signed-off-by: J. Bruce Fields 
Signed-off-by: Trond Myklebust 
Signed-off-by: Sasha Levin

net: disable netpoll on fresh napis

2020-09-12T09:45:33+00:00

[ Upstream commit 96e97bc07e90f175a8980a22827faf702ca4cb30 ]

napi_disable() makes sure to set the NAPI_STATE_NPSVC bit to prevent
netpoll from accessing rings before init is complete. However, the
same is not done for fresh napi instances in netif_napi_add(),
even though we expect NAPI instances to be added as disabled.

This causes crashes during driver reconfiguration (enabling XDP,
changing the channel count) - if there is any printk() after
netif_napi_add() but before napi_enable().

To ensure memory ordering is correct we need to use RCU accessors.

Reported-by: Rob Sherwood 
Fixes: 2d8bff12699a ("netpoll: Close race condition between poll_one_napi and napi_disable")
Signed-off-by: Jakub Kicinski 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sctp: not disable bh in the whole sctp_get_port_local()

2020-09-12T09:45:33+00:00

[ Upstream commit 3106ecb43a05dc3e009779764b9da245a5d082de ]

With disabling bh in the whole sctp_get_port_local(), when
snum == 0 and too many ports have been used, the do-while
loop will take the cpu for a long time and cause cpu stuck:

  [ ] watchdog: BUG: soft lockup - CPU#11 stuck for 22s!
  [ ] RIP: 0010:native_queued_spin_lock_slowpath+0x4de/0x940
  [ ] Call Trace:
  [ ]  _raw_spin_lock+0xc1/0xd0
  [ ]  sctp_get_port_local+0x527/0x650 [sctp]
  [ ]  sctp_do_bind+0x208/0x5e0 [sctp]
  [ ]  sctp_autobind+0x165/0x1e0 [sctp]
  [ ]  sctp_connect_new_asoc+0x355/0x480 [sctp]
  [ ]  __sctp_connect+0x360/0xb10 [sctp]

There's no need to disable bh in the whole function of
sctp_get_port_local. So fix this cpu stuck by removing
local_bh_disable() called at the beginning, and using
spin_lock_bh() instead.

The same thing was actually done for inet_csk_get_port() in
Commit ea8add2b1903 ("tcp/dccp: better use of ephemeral
ports in bind()").

Thanks to Marcelo for pointing the buggy code out.

v1->v2:
  - use cond_resched() to yield cpu to other tasks if needed,
    as Eric noticed.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Ying Xu 
Signed-off-by: Xin Long 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

cfg80211: regulatory: reject invalid hints

2020-09-12T09:45:32+00:00

commit 47caf685a6854593348f216e0b489b71c10cbe03 upstream.

Reject invalid hints early in order to not cause a kernel
WARN later if they're restored to or similar.

Reported-by: syzbot+d451401ffd00a60677ee@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=d451401ffd00a60677ee
Link: https://lore.kernel.org/r/20200819084648.13956-1-johannes@sipsolutions.net
Signed-off-by: Johannes Berg 
Signed-off-by: Greg Kroah-Hartman

net: initialize fastreuse on inet_inherit_port

2020-09-12T09:45:31+00:00

commit d76f3351cea2d927fdf70dd7c06898235035e84e upstream.

In the case of TPROXY, bind_conflict optimizations for SO_REUSEADDR or
SO_REUSEPORT are broken, possibly resulting in O(n) instead of O(1) bind
behaviour or in the incorrect reuse of a bind.

the kernel keeps track for each bind_bucket if all sockets in the
bind_bucket support SO_REUSEADDR or SO_REUSEPORT in two fastreuse flags.
These flags allow skipping the costly bind_conflict check when possible
(meaning when all sockets have the proper SO_REUSE option).

For every socket added to a bind_bucket, these flags need to be updated.
As soon as a socket that does not support reuse is added, the flag is
set to false and will never go back to true, unless the bind_bucket is
deleted.

Note that there is no mechanism to re-evaluate these flags when a socket
is removed (this might make sense when removing a socket that would not
allow reuse; this leaves room for a future patch).

For this optimization to work, it is mandatory that these flags are
properly initialized and updated.

When a child socket is created from a listen socket in
__inet_inherit_port, the TPROXY case could create a new bind bucket
without properly initializing these flags, thus preventing the
optimization to work. Alternatively, a socket not allowing reuse could
be added to an existing bind bucket without updating the flags, causing
bind_conflict to never be called as it should.

Call inet_csk_update_fastreuse when __inet_inherit_port decides to create
a new bind_bucket or use a different bind_bucket than the one of the
listen socket.

Fixes: 093d282321da ("tproxy: fix hash locking issue when using port redirection in __inet_inherit_port()")
Acked-by: Matthieu Baerts
Signed-off-by: Tim Froidcoeur
Signed-off-by: David S. Miller
Signed-off-by: Tim Froidcoeur
Signed-off-by: Greg Kroah-Hartman

net: refactor bind_bucket fastreuse into helper

2020-09-12T09:45:31+00:00

commit 62ffc589abb176821662efc4525ee4ac0b9c3894 upstream.

Refactor the fastreuse update code in inet_csk_get_port into a small
helper function that can be called from other places.

Acked-by: Matthieu Baerts 
Signed-off-by: Tim Froidcoeur 
Signed-off-by: David S. Miller 
Signed-off-by: Tim Froidcoeur 
Signed-off-by: Greg Kroah-Hartman

netfilter: nf_tables: fix destination register zeroing

2020-09-12T09:45:27+00:00

[ Upstream commit 1e105e6afa6c3d32bfb52c00ffa393894a525c27 ]

Following bug was reported via irc:
nft list ruleset
   set knock_candidates_ipv4 {
      type ipv4_addr . inet_service
      size 65535
      elements = { 127.0.0.1 . 123,
                   127.0.0.1 . 123 }
      }
 ..
   udp dport 123 add @knock_candidates_ipv4 { ip saddr . 123 }
   udp dport 123 add @knock_candidates_ipv4 { ip saddr . udp dport }

It should not have been possible to add a duplicate set entry.

After some debugging it turned out that the problem is the immediate
value (123) in the second-to-last rule.

Concatenations use 32bit registers, i.e. the elements are 8 bytes each,
not 6 and it turns out the kernel inserted

inet firewall @knock_candidates_ipv4
        element 0100007f ffff7b00  : 0 [end]
        element 0100007f 00007b00  : 0 [end]

Note the non-zero upper bits of the first element.  It turns out that
nft_immediate doesn't zero the destination register, but this is needed
when the length isn't a multiple of 4.

Furthermore, the zeroing in nft_payload is broken.  We can't use
[len / 4] = 0 -- if len is a multiple of 4, index is off by one.

Skip zeroing in this case and use a conditional instead of (len -1) / 4.

Fixes: 49499c3e6e18 ("netfilter: nf_tables: switch registers to 32 bit addressing")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

batman-adv: bla: use netif_rx_ni when not in interrupt context

2020-09-12T09:45:27+00:00

[ Upstream commit 279e89b2281af3b1a9f04906e157992c19c9f163 ]

batadv_bla_send_claim() gets called from worker thread context through
batadv_bla_periodic_work(), thus netif_rx_ni needs to be used in that
case. This fixes "NOHZ: local_softirq_pending 08" log messages seen
when batman-adv is enabled.

Fixes: 23721387c409 ("batman-adv: add basic bridge loop avoidance code")
Signed-off-by: Jussi Kivilinna 
Signed-off-by: Sven Eckelmann 
Signed-off-by: Simon Wunderlich 
Signed-off-by: Sasha Levin

batman-adv: Avoid uninitialized chaddr when handling DHCP

2020-09-12T09:45:27+00:00

[ Upstream commit 303216e76dcab6049c9d42390b1032f0649a8206 ]

The gateway client code can try to optimize the delivery of DHCP packets to
avoid broadcasting them through the whole mesh. But also transmissions to
the client can be optimized by looking up the destination via the chaddr of
the DHCP packet.

But the chaddr is currently only done when chaddr is fully inside the
non-paged area of the skbuff. Otherwise it will not be initialized and the
unoptimized path should have been taken.

But the implementation didn't handle this correctly. It didn't retrieve the
correct chaddr but still tried to perform the TT lookup with this
uninitialized memory.

Reported-by: syzbot+ab16e463b903f5a37036@syzkaller.appspotmail.com
Fixes: 6c413b1c22a2 ("batman-adv: send every DHCP packet as bat-unicast")
Signed-off-by: Sven Eckelmann 
Acked-by: Antonio Quartulli 
Signed-off-by: Simon Wunderlich 
Signed-off-by: Sasha Levin

tipc: fix uninit skb->data in tipc_nl_compat_dumpit()

2020-09-03T09:19:22+00:00

[ Upstream commit 47733f9daf4fe4f7e0eb9e273f21ad3a19130487 ]

__tipc_nl_compat_dumpit() has two callers, and it expects them to
pass a valid nlmsghdr via arg->data. This header is artificial and
crafted just for __tipc_nl_compat_dumpit().

tipc_nl_compat_publ_dump() does so by putting a genlmsghdr as well
as some nested attribute, TIPC_NLA_SOCK. But the other caller
tipc_nl_compat_dumpit() does not, this leaves arg->data uninitialized
on this call path.

Fix this by just adding a similar nlmsghdr without any payload in
tipc_nl_compat_dumpit().

This bug exists since day 1, but the recent commit 6ea67769ff33
("net: tipc: prepare attrs in __tipc_nl_compat_dumpit()") makes it
easier to appear.

Reported-and-tested-by: syzbot+0e7181deafa7e0b79923@syzkaller.appspotmail.com
Fixes: d0796d1ef63d ("tipc: convert legacy nl bearer dump to nl compat")
Cc: Jon Maloy 
Cc: Ying Xue 
Cc: Richard Alpe 
Signed-off-by: Cong Wang 
Acked-by: Ying Xue 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman