linux-stable.git/net/ipv4, branch v5.6.4

udp: initialize is_flist with 0 in udp_gro_receive

2020-04-08T07:11:04+00:00

[ Upstream commit bde1b56f898ca8112912d7b36e55e1543b3be0cf ]

Without NAPI_GRO_CB(skb)->is_flist initialized, when the dev doesn't
support NETIF_F_GRO_FRAGLIST, is_flist can still be set and fraglist
will be used in udp_gro_receive().

So fix it by initializing is_flist with 0 in udp_gro_receive.

Fixes: 9fd1ff5d2ac7 ("udp: Support UDP fraglist GRO/GSO.")
Signed-off-by: Xin Long 
Acked-by: Steffen Klassert 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net, ip_tunnel: fix interface lookup with no key

2020-04-08T07:11:03+00:00

[ Upstream commit 25629fdaff2ff509dd0b3f5ff93d70a75e79e0a1 ]

when creating a new ipip interface with no local/remote configuration,
the lookup is done with TUNNEL_NO_KEY flag, making it impossible to
match the new interface (only possible match being fallback or metada
case interface); e.g: `ip link add tunl1 type ipip dev eth0`

To fix this case, adding a flag check before the key comparison so we
permit to match an interface with no local/remote config; it also avoids
breaking possible userland tools relying on TUNNEL_NO_KEY flag and
uninitialised key.

context being on my side, I'm creating an extra ipip interface attached
to the physical one, and moving it to a dedicated namespace.

Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.")
Signed-off-by: William Dauchy 
Signed-off-by: Nicolas Dichtel 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv4: fix a RCU-list lock in fib_triestat_seq_show

2020-04-08T07:11:02+00:00

[ Upstream commit fbe4e0c1b298b4665ee6915266c9d6c5b934ef4a ]

fib_triestat_seq_show() calls hlist_for_each_entry_rcu(tb, head,
tb_hlist) without rcu_read_lock() will trigger a warning,

 net/ipv4/fib_trie.c:2579 RCU-list traversed in non-reader section!!

 other info that might help us debug this:

 rcu_scheduler_active = 2, debug_locks = 1
 1 lock held by proc01/115277:
  #0: c0000014507acf00 (&p->lock){+.+.}-{3:3}, at: seq_read+0x58/0x670

 Call Trace:
  dump_stack+0xf4/0x164 (unreliable)
  lockdep_rcu_suspicious+0x140/0x164
  fib_triestat_seq_show+0x750/0x880
  seq_read+0x1a0/0x670
  proc_reg_read+0x10c/0x1b0
  __vfs_read+0x3c/0x70
  vfs_read+0xac/0x170
  ksys_read+0x7c/0x140
  system_call+0x5c/0x68

Fix it by adding a pair of rcu_read_lock/unlock() and use
cond_resched_rcu() to avoid the situation where walking of a large
number of items  may prevent scheduling for a long time.

Signed-off-by: Qian Cai 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

2020-03-27T23:18:51+00:00

Daniel Borkmann says:

====================
pull-request: bpf 2020-03-27

The following pull-request contains BPF updates for your *net* tree.

We've added 3 non-merge commits during the last 4 day(s) which contain
a total of 4 files changed, 25 insertions(+), 20 deletions(-).

The main changes are:

1) Explicitly memset the bpf_attr structure on bpf() syscall to avoid
   having to rely on compiler to do so. Issues have been noticed on
   some compilers with padding and other oddities where the request was
   then unexpectedly rejected, from Greg Kroah-Hartman.

2) Sanitize the bpf_struct_ops TCP congestion control name in order to
   avoid problematic characters such as whitespaces, from Martin KaFai Lau.
====================

Signed-off-by: David S. Miller

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec

2020-03-27T21:56:55+00:00

Steffen Klassert says:

====================
pull request (net): ipsec 2020-03-27

1) Handle NETDEV_UNREGISTER for xfrm device to handle asynchronous
   unregister events cleanly. From Raed Salem.

2) Fix vti6 tunnel inter address family TX through bpf_redirect().
   From Nicolas Dichtel.

3) Fix lenght check in verify_sec_ctx_len() to avoid a
   slab-out-of-bounds. From Xin Long.

4) Add a missing verify_sec_ctx_len check in xfrm_add_acquire
   to avoid a possible out-of-bounds to access. From Xin Long.

5) Use built-in RCU list checking of hlist_for_each_entry_rcu
   to silence false lockdep warning in __xfrm6_tunnel_spi_lookup
   when CONFIG_PROVE_RCU_LIST is enabled. From Madhuparna Bhowmik.

6) Fix a panic on esp offload when crypto is done asynchronously.
   From Xin Long.

7) Fix a skb memory leak in an error path of vti6_rcv.
   From Torsten Hilbrich.

8) Fix a race that can lead to a doulbe free in xfrm_policy_timer.
   From Xin Long.
====================

Signed-off-by: David S. Miller

ipv4: fix a RCU-list lock in inet_dump_fib()

2020-03-24T03:59:40+00:00

There is a place,

inet_dump_fib()
  fib_table_dump
    fn_trie_dump_leaf()
      hlist_for_each_entry_rcu()

without rcu_read_lock() will trigger a warning,

 WARNING: suspicious RCU usage
 -----------------------------
 net/ipv4/fib_trie.c:2216 RCU-list traversed in non-reader section!!

 other info that might help us debug this:

 rcu_scheduler_active = 2, debug_locks = 1
 1 lock held by ip/1923:
  #0: ffffffff8ce76e40 (rtnl_mutex){+.+.}, at: netlink_dump+0xd6/0x840

 Call Trace:
  dump_stack+0xa1/0xea
  lockdep_rcu_suspicious+0x103/0x10d
  fn_trie_dump_leaf+0x581/0x590
  fib_table_dump+0x15f/0x220
  inet_dump_fib+0x4ad/0x5d0
  netlink_dump+0x350/0x840
  __netlink_dump_start+0x315/0x3e0
  rtnetlink_rcv_msg+0x4d1/0x720
  netlink_rcv_skb+0xf0/0x220
  rtnetlink_rcv+0x15/0x20
  netlink_unicast+0x306/0x460
  netlink_sendmsg+0x44b/0x770
  __sys_sendto+0x259/0x270
  __x64_sys_sendto+0x80/0xa0
  do_syscall_64+0x69/0xf4
  entry_SYSCALL_64_after_hwframe+0x49/0xb3

Fixes: 18a8021a7be3 ("net/ipv4: Plumb support for filtering route dumps")
Signed-off-by: Qian Cai 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller

tcp: repair: fix TCP_QUEUE_SEQ implementation

2020-03-23T20:02:01+00:00

When application uses TCP_QUEUE_SEQ socket option to
change tp->rcv_next, we must also update tp->copied_seq.

Otherwise, stuff relying on tcp_inq() being precise can
eventually be confused.

For example, tcp_zerocopy_receive() might crash because
it does not expect tcp_recv_skb() to return NULL.

We could add tests in various places to fix the issue,
or simply make sure tcp_inq() wont return a random value,
and leave fast path as it is.

Note that this fixes ioctl(fd, SIOCINQ, &val) at the same
time.

Fixes: ee9952831cfd ("tcp: Initial repair mode")
Fixes: 05255b823a61 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Signed-off-by: David S. Miller

tcp: also NULL skb->dev when copy was needed

2020-03-21T02:36:38+00:00

In rare cases retransmit logic will make a full skb copy, which will not
trigger the zeroing added in recent change
b738a185beaa ("tcp: ensure skb->dev is NULL before leaving TCP stack").

Cc: Eric Dumazet 
Fixes: 75c119afe14f ("tcp: implement rb-tree based retransmit queue")
Fixes: 28f8bfd1ac94 ("netfilter: Support iif matches in POSTROUTING")
Signed-off-by: Florian Westphal 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

tcp: ensure skb->dev is NULL before leaving TCP stack

2020-03-20T04:35:55+00:00

skb->rbnode is sharing three skb fields : next, prev, dev

When a packet is sent, TCP keeps the original skb (master)
in a rtx queue, which was converted to rbtree a while back.

__tcp_transmit_skb() is responsible to clone the master skb,
and add the TCP header to the clone before sending it
to network layer.

skb_clone() already clears skb->next and skb->prev, but copies
the master oskb->dev into the clone.

We need to clear skb->dev, otherwise lower layers could interpret
the value as a pointer to a netdev.

This old bug surfaced recently when commit 28f8bfd1ac94
("netfilter: Support iif matches in POSTROUTING") was merged.

Before this netfilter commit, skb->dev value was ignored and
changed before reaching dev_queue_xmit()

Fixes: 75c119afe14f ("tcp: implement rb-tree based retransmit queue")
Fixes: 28f8bfd1ac94 ("netfilter: Support iif matches in POSTROUTING")
Signed-off-by: Eric Dumazet 
Reported-by: Martin Zaharinov 
Cc: Florian Westphal 
Cc: Pablo Neira Ayuso 
Signed-off-by: David S. Miller

bpf: Sanitize the bpf_struct_ops tcp-cc name

2020-03-17T19:40:19+00:00

The bpf_struct_ops tcp-cc name should be sanitized in order to
avoid problematic chars (e.g. whitespaces).

This patch reuses the bpf_obj_name_cpy() for accepting the same set
of characters in order to keep a consistent bpf programming experience.
A "size" param is added.  Also, the strlen is returned on success so
that the caller (like the bpf_tcp_ca here) can error out on empty name.
The existing callers of the bpf_obj_name_cpy() only need to change the
testing statement to "if (err < 0)".  For all these existing callers,
the err will be overwritten later, so no extra change is needed
for the new strlen return value.

v3:
  - reverse xmas tree style
v2:
  - Save the orig_src to avoid "end - size" (Andrii)

Fixes: 0baf26b0fcd7 ("bpf: tcp: Support tcp_congestion_ops in bpf")
Signed-off-by: Martin KaFai Lau 
Signed-off-by: Daniel Borkmann 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20200314010209.1131542-1-kafai@fb.com