linux-toradex.git/net/l2tp/l2tp_ip.c, branch v6.3-rc3

l2tp: use add READ_ONCE() to fetch sk->sk_bound_dev_if

2022-05-16T09:31:06+00:00

Use READ_ONCE() in paths not holding the socket lock.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

net: remove noblock parameter from recvmsg() entities

2022-04-12T13:00:25+00:00

The internal recvmsg() functions have two parameters 'flags' and 'noblock'
that were merged inside skb_recv_datagram(). As a follow up patch to commit
f4b41f062c42 ("net: remove noblock parameter from skb_recv_datagram()")
this patch removes the separate 'noblock' parameter for recvmsg().

Analogue to the referenced patch for skb_recv_datagram() the 'flags' and
'noblock' parameters are unnecessarily split up with e.g.

err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
                           flags & ~MSG_DONTWAIT, &addr_len);

or in

err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg,
                      sk, msg, size, flags & MSG_DONTWAIT,
                      flags & ~MSG_DONTWAIT, &addr_len);

instead of simply using only flags all the time and check for MSG_DONTWAIT
where needed (to preserve for the formerly separated no(n)block condition).

Signed-off-by: Oliver Hartkopp 
Link: https://lore.kernel.org/r/20220411124955.154876-1-socketcan@hartkopp.net
Signed-off-by: Paolo Abeni

net: remove noblock parameter from skb_recv_datagram()

2022-04-06T12:45:26+00:00

skb_recv_datagram() has two parameters 'flags' and 'noblock' that are
merged inside skb_recv_datagram() by 'flags | (noblock ? MSG_DONTWAIT : 0)'

As 'flags' may contain MSG_DONTWAIT as value most callers split the 'flags'
into 'flags' and 'noblock' with finally obsolete bit operations like this:

skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &rc);

And this is not even done consistently with the 'flags' parameter.

This patch removes the obsolete and costly splitting into two parameters
and only performs bit operations when really needed on the caller side.

One missing conversion thankfully reported by kernel test robot. I missed
to enable kunit tests to build the mctp code.

Reported-by: kernel test robot 
Signed-off-by: Oliver Hartkopp 
Signed-off-by: David S. Miller

l2tp: Fix spelling mistakes

2021-06-07T21:08:30+00:00

Fix some spelling mistakes in comments:
negociated  ==> negotiated
dont  ==> don't

Signed-off-by: Zheng Yongjun 
Signed-off-by: David S. Miller

net: Remove the member netns_ok

2021-05-17T22:29:35+00:00

Every protocol has the 'netns_ok' member and it is euqal to 1. The
'if (!prot->netns_ok)' always false in inet_add_protocol().

Signed-off-by: Yejune Deng 
Signed-off-by: David S. Miller

l2tp: make magic feather checks more useful

2020-09-03T19:19:03+00:00

The l2tp tunnel and session structures contain a "magic feather" field
which was originally intended to help trace lifetime bugs in the code.

Since the introduction of the shared kernel refcount code in refcount.h,
and l2tp's porting to those APIs, we are covered by the refcount code's
checks and warnings.  Duplicating those checks in the l2tp code isn't
useful.

However, magic feather checks are still useful to help to detect bugs
stemming from misuse/trampling of the sk_user_data pointer in struct
sock.  The l2tp code makes extensive use of sk_user_data to stash
pointers to the tunnel and session structures, and if another subsystem
overwrites sk_user_data it's important to detect this.

As such, rework l2tp's magic feather checks to focus on validating the
tunnel and session data structures when they're extracted from
sk_user_data.

 * Add a new accessor function l2tp_sk_to_tunnel which contains a magic
   feather check, and is used by l2tp_core and l2tp_ip[6]
 * Comment l2tp_udp_encap_recv which doesn't use this new accessor function
   because of the specific nature of the codepath it is called in
 * Drop l2tp_session_queue_purge's check on the session magic feather:
   it is called from code which is walking the tunnel session list, and
   hence doesn't need validation
 * Drop l2tp_session_free's check on the tunnel magic feather: the
   intention of this check is covered by refcount.h's reference count
   sanity checking
 * Add session magic validation in pppol2tp_ioctl.  On failure return
   -EBADF, which mirrors the approach in pppol2tp_[sg]etsockopt.

Signed-off-by: Tom Parkin 
Signed-off-by: David S. Miller

l2tp: don't log data frames

2020-08-22T19:44:37+00:00

l2tp had logging to trace data frame receipt and transmission, including
code to dump packet contents.  This was originally intended to aid
debugging of core l2tp packet handling, but is of limited use now that
code is stable.

Signed-off-by: Tom Parkin 
Signed-off-by: David S. Miller

l2tp: tweak exports for l2tp_recv_common and l2tp_ioctl

2020-07-30T23:45:31+00:00

All of the l2tp subsystem's exported symbols are exported using
EXPORT_SYMBOL_GPL, except for l2tp_recv_common and l2tp_ioctl.

These functions alone are not useful without the rest of the l2tp
infrastructure, so there's no practical benefit to these symbols using a
different export policy.

Change these exports to use EXPORT_SYMBOL_GPL for consistency with the
rest of l2tp.

Signed-off-by: Tom Parkin 
Signed-off-by: David S. Miller

l2tp: avoid multiple assignments

2020-07-25T00:19:14+00:00

checkpatch warns about multiple assignments.

Update l2tp accordingly.

Signed-off-by: Tom Parkin 
Signed-off-by: David S. Miller

l2tp: cleanup comparisons to NULL

2020-07-23T18:54:40+00:00

checkpatch warns about comparisons to NULL, e.g.

        CHECK: Comparison to NULL could be written "!rt"
        #474: FILE: net/l2tp/l2tp_ip.c:474:
        +       if (rt == NULL) {

These sort of comparisons are generally clearer and more readable
the way checkpatch suggests, so update l2tp accordingly.

Signed-off-by: Tom Parkin 
Signed-off-by: David S. Miller