linux-toradex.git/include/linux/netlink.h, branch v5.12-rc6

netlink: add tracepoint at NL_SET_ERR_MSG

2021-02-05T02:05:59+00:00

Often userspace won't request the extack information, or they don't log it
because of log level or so, and even when they do, sometimes it's not
enough to know exactly what caused the error.

Netlink extack is the standard way of reporting erros with descriptive
error messages. With a trace point on it, we then can know exactly where
the error happened, regardless of userspace app. Also, we can even see if
the err msg was overwritten.

The wrapper do_trace_netlink_extack() is because trace points shouldn't be
called from .h files, as trace points are not that small, and the function
call to do_trace_netlink_extack() on the macros is not protected by
tracepoint_enabled() because the macros are called from modules, and this
would require exporting some trace structs. As this is error path, it's
better to export just the wrapper instead.

v2: removed leftover tracepoint declaration

Signed-off-by: Marcelo Ricardo Leitner 
Reviewed-by: David Ahern 
Link: https://lore.kernel.org/r/4546b63e67b2989789d146498b13cc09e1fdc543.1612403190.git.marcelo.leitner@gmail.com
Signed-off-by: Jakub Kicinski

rtnetlink: fix data overflow in rtnl_calcit()

2020-10-22T01:24:08+00:00

"ip addr show" command execute error when we have a physical
network card with a large number of VFs

The return value of if_nlmsg_size() in rtnl_calcit() will exceed
range of u16 data type when any network cards has a larger number of
VFs. rtnl_vfinfo_size() will significant increase needed dump size when
the value of num_vfs is larger.

Eventually we get a wrong value of min_ifinfo_dump_size because of overflow
which decides the memory size needed by netlink dump and netlink_dump()
will return -EMSGSIZE because of not enough memory was allocated.

So fix it by promoting  min_dump_alloc data type to u32 to
avoid whole netlink message size overflow and it's also align
with the data type of struct netlink_callback{}.min_dump_alloc
which is assigned by return value of rtnl_calcit()

Signed-off-by: Di Zhu 
Link: https://lore.kernel.org/r/20201021020053.1401-1-zhudi21@huawei.com
Signed-off-by: Jakub Kicinski

netlink: export policy in extended ACK

2020-10-10T03:22:32+00:00

Add a new attribute NLMSGERR_ATTR_POLICY to the extended ACK
to advertise the policy, e.g. if an attribute was out of range,
you'll know the range that's permissible.

Add new NL_SET_ERR_MSG_ATTR_POL() and NL_SET_ERR_MSG_ATTR_POL()
macros to set this, since realistically it's only useful to do
this when the bad attribute (offset) is also returned.

Use it in lib/nlattr.c which practically does all the policy
validation.

v2:
 - add and use netlink_policy_dump_attr_size_estimate()
v3:
 - remove redundant break
v4:
 - really remove redundant break ... sorry

Reviewed-by: Jakub Kicinski 
Signed-off-by: Johannes Berg 
Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-03-26T01:58:11+00:00

Overlapping header include additions in macsec.c

A bug fix in 'net' overlapping with the removal of 'version'
string in ena_netdev.c

Overlapping test additions in selftests Makefile

Overlapping PCI ID table adjustments in iwlwifi driver.

Signed-off-by: David S. Miller

netlink: check for null extack in cookie helpers

2020-03-24T04:19:20+00:00

Unlike NL_SET_ERR_* macros, nl_set_extack_cookie_u64() and
nl_set_extack_cookie_u32() helpers do not check extack argument for null
and neither do their callers, as syzbot recently discovered for
ethnl_parse_header().

Instead of fixing the callers and leaving the trap in place, add check of
null extack to both helpers to make them consistent with NL_SET_ERR_*
macros.

v2: drop incorrect second Fixes tag

Fixes: 2363d73a2f3e ("ethtool: reject unrecognized request flags")
Reported-by: syzbot+258a9089477493cea67b@syzkaller.appspotmail.com
Signed-off-by: Michal Kubecek 
Signed-off-by: David S. Miller

netlink: add nl_set_extack_cookie_u32()

2020-03-16T09:04:24+00:00

Similar to existing nl_set_extack_cookie_u64(), add new helper
nl_set_extack_cookie_u32() which sets extack cookie to a u32 value.

Signed-off-by: Michal Kubecek 
Signed-off-by: David S. Miller

bpf: inet_diag: Dump bpf_sk_storages in inet_diag_dump()

2020-02-28T02:50:19+00:00

This patch will dump out the bpf_sk_storages of a sk
if the request has the INET_DIAG_REQ_SK_BPF_STORAGES nlattr.

An array of SK_DIAG_BPF_STORAGE_REQ_MAP_FD can be specified in
INET_DIAG_REQ_SK_BPF_STORAGES to select which bpf_sk_storage to dump.
If no map_fd is specified, all bpf_sk_storages of a sk will be dumped.

bpf_sk_storages can be added to the system at runtime.  It is difficult
to find a proper static value for cb->min_dump_alloc.

This patch learns the nlattr size required to dump the bpf_sk_storages
of a sk.  If it happens to be the very first nlmsg of a dump and it
cannot fit the needed bpf_sk_storages,  it will try to expand the
skb by "pskb_expand_head()".

Instead of expanding it in inet_sk_diag_fill(), it is expanded at a
sleepable context in __inet_diag_dump() so __GFP_DIRECT_RECLAIM can
be used.  In __inet_diag_dump(), it will retry as long as the
skb is empty and the cb->min_dump_alloc becomes larger than before.
cb->min_dump_alloc is bounded by KMALLOC_MAX_SIZE.  The min_dump_alloc
is also changed from 'u16' to 'u32' to accommodate a sk that may have
a few large bpf_sk_storages.

The updated cb->min_dump_alloc will also be used to allocate the skb in
the next dump.  This logic already exists in netlink_dump().

Here is the sample output of a locally modified 'ss' and it could be made
more readable by using BTF later:
[root@arch-fb-vm1 ~]# ss --bpf-map-id 14 --bpf-map-id 13 -t6an 'dst [::1]:8989'
State Recv-Q Send-Q Local Address:Port  Peer Address:PortProcess
ESTAB 0      0              [::1]:51072        [::1]:8989
	 bpf_map_id:14 value:[ 3feb ]
	 bpf_map_id:13 value:[ 3f ]
ESTAB 0      0              [::1]:51070        [::1]:8989
	 bpf_map_id:14 value:[ 3feb ]
	 bpf_map_id:13 value:[ 3f ]

[root@arch-fb-vm1 ~]# ~/devshare/github/iproute2/misc/ss --bpf-maps -t6an 'dst [::1]:8989'
State         Recv-Q         Send-Q                   Local Address:Port                    Peer Address:Port         Process
ESTAB         0              0                                [::1]:51072                          [::1]:8989
	 bpf_map_id:14 value:[ 3feb ]
	 bpf_map_id:13 value:[ 3f ]
	 bpf_map_id:12 value:[ 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000... total:65407 ]
ESTAB         0              0                                [::1]:51070                          [::1]:8989
	 bpf_map_id:14 value:[ 3feb ]
	 bpf_map_id:13 value:[ 3f ]
	 bpf_map_id:12 value:[ 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000... total:65407 ]

Signed-off-by: Martin KaFai Lau 
Signed-off-by: Alexei Starovoitov 
Acked-by: Song Liu 
Link: https://lore.kernel.org/bpf/20200225230427.1976129-1-kafai@fb.com

netlink: use 48 byte ctx instead of 6 signed longs for callback

2019-07-02T02:12:10+00:00

People are inclined to stuff random things into cb->args[n] because it
looks like an array of integers. Sometimes people even put u64s in there
with comments noting that a certain member takes up two slots. The
horror! Really this should mirror the usage of skb->cb, which are just
48 opaque bytes suitable for casting a struct. Then people can create
their usual casting macros for accessing strongly typed members of a
struct.

As a plus, this also gives us the same amount of space on 32bit and 64bit.

Signed-off-by: Jason A. Donenfeld 
Reviewed-by: Johannes Berg 
Signed-off-by: David S. Miller

net: netlink: add helper to retrieve NETLINK_F_STRICT_CHK

2019-01-19T18:09:58+00:00

Dumps can read state of the NETLINK_F_STRICT_CHK flag from
a field in the callback structure.  For non-dump GET requests
we need a way to access the state of that flag from a socket.

Signed-off-by: Jakub Kicinski 
Signed-off-by: David S. Miller

linux/netlink.h: drop unnecessary extern prefix

2018-12-21T00:43:54+00:00

Don't need extern prefix before function prototypes.
Checkpatch has complained about this for a couple of years.

Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller