linux-stable.git/net/netlink, branch linux-5.0.y

genetlink: Fix a memory leak on error path

2019-04-03T04:27:22+00:00

[ Upstream commit ceabee6c59943bdd5e1da1a6a20dc7ee5f8113a2 ]

In genl_register_family(), when idr_alloc() fails,
we forget to free the memory we possibly allocate for
family->attrbuf.

Reported-by: Hulk Robot 
Fixes: 2ae0f17df1cd ("genetlink: use idr to track families")
Signed-off-by: YueHaibing 
Reviewed-by: Kirill Tkhai 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: netlink: rename NETLINK_DUMP_STRICT_CHK -> NETLINK_GET_STRICT_CHK

2018-12-14T19:44:31+00:00

NETLINK_DUMP_STRICT_CHK can be used for all GET requests,
dumps as well as doit handlers.  Replace the DUMP in the
name with GET make that clearer.

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

netlink: Add answer_flags to netlink_callback

2018-10-16T07:13:12+00:00

With dump filtering we need a way to ensure the NLM_F_DUMP_FILTERED
flag is set on a message back to the user if the data returned is
influenced by some input attributes. Normally this can be done as
messages are added to the skb, but if the filter results in no data
being returned, the user could be confused as to why.

This patch adds answer_flags to the netlink_callback allowing dump
handlers to set the NLM_F_DUMP_FILTERED at a minimum in the
NLMSG_DONE message ensuring the flag gets back to the user.

The netlink_callback space is initialized to 0 via a memset in
__netlink_dump_start, so init of the new answer_flags is covered.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

netlink: Add new socket option to enable strict checking on dumps

2018-10-08T17:39:04+00:00

Add a new socket option, NETLINK_DUMP_STRICT_CHK, that userspace
can use via setsockopt to request strict checking of headers and
attributes on dump requests.

To get dump features such as kernel side filtering based on data in
the header or attributes appended to the dump request, userspace
must call setsockopt() for NETLINK_DUMP_STRICT_CHK and a non-zero
value. Since the netlink sock and its flags are private to the
af_netlink code, the strict checking flag is passed to dump handlers
via a flag in the netlink_callback struct.

For old userspace on new kernel there is no impact as all of the data
checks in later patches are wrapped in a check on the new strict flag.

For new userspace on old kernel, the setsockopt will fail and even if
new userspace sets data in the headers and appended attributes the
kernel will silently ignore it. Moving forward when the setsockopt
succeeds, the new userspace on old kernel means the dump request can
pass an attribute the kernel does not understand. The dump will then
fail as the older kernel does not understand it.

New userspace on new kernel setting the socket option gets the benefit
of the improved data dump.

Kernel side the NETLINK_DUMP_STRICT_CHK uapi is converted to a generic
NETLINK_F_STRICT_CHK flag which can potentially be leveraged for tighter
checking on the NEW, DEL, and SET commands.

Signed-off-by: David Ahern 
Acked-by: Christian Brauner 
Signed-off-by: David S. Miller

netlink: Pass extack to dump handlers

2018-10-08T17:39:03+00:00

Declare extack in netlink_dump and pass to dump handlers via
netlink_callback. Add any extack message after the dump_done_errno
allowing error messages to be returned. This will be useful when
strict checking is done on dump requests, returning why the dump
fails EINVAL.

Signed-off-by: David Ahern 
Acked-by: Christian Brauner 
Signed-off-by: David S. Miller

netlink: remove hash::nelems check in netlink_insert

2018-09-12T07:08:44+00:00

The type of hash::nelems has been changed from size_t to atom_t
which in fact is int, so not need to check if BITS_PER_LONG, that
is bit number of size_t, is bigger than 32

and rht_grow_above_max() will be called to check if hashtable is
too big, ensure it can not bigger than 1<<31

Signed-off-by: Zhang Yu 
Signed-off-by: Li RongQing 
Signed-off-by: David S. Miller

netlink: Make groups check less stupid in netlink_bind()

2018-09-06T05:11:33+00:00

As Linus noted, the test for 0 is needless, groups type can follow the
usual kernel style and 8*sizeof(unsigned long) is BITS_PER_LONG:

> The code [..] isn't technically incorrect...
> But it is stupid.
> Why stupid? Because the test for 0 is pointless.
>
> Just doing
>        if (nlk->ngroups < 8*sizeof(groups))
>                groups &= (1UL << nlk->ngroups) - 1;
>
> would have been fine and more understandable, since the "mask by shift
> count" already does the right thing for a ngroups value of 0. Now that
> test for zero makes me go "what's special about zero?". It turns out
> that the answer to that is "nothing".
[..]
> The type of "groups" is kind of silly too.
>
> Yeah, "long unsigned int" isn't _technically_ wrong. But we normally
> call that type "unsigned long".

Cleanup my piece of pointlessness.

Cc: "David S. Miller" 
Cc: Herbert Xu 
Cc: Steffen Klassert 
Cc: netdev@vger.kernel.org
Fairly-blamed-by: Linus Torvalds 
Signed-off-by: Dmitry Safonov 
Signed-off-by: David S. Miller

Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net

2018-08-05T20:04:31+00:00

Lots of overlapping changes, mostly trivial in nature.

The mlxsw conflict was resolving using the example
resolution at:

https://github.com/jpirko/linux_mlxsw/blob/combined_queue/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c

Signed-off-by: David S. Miller

netlink: Don't shift on 64 for ngroups

2018-08-05T00:52:51+00:00

It's legal to have 64 groups for netlink_sock.

As user-supplied nladdr->nl_groups is __u32, it's possible to subscribe
only to first 32 groups.

The check for correctness of .bind() userspace supplied parameter
is done by applying mask made from ngroups shift. Which broke Android
as they have 64 groups and the shift for mask resulted in an overflow.

Fixes: 61f4b23769f0 ("netlink: Don't shift with UB on nlk->ngroups")
Cc: "David S. Miller" 
Cc: Herbert Xu 
Cc: Steffen Klassert 
Cc: netdev@vger.kernel.org
Cc: stable@vger.kernel.org
Reported-and-Tested-by: Nathan Chancellor 
Signed-off-by: Dmitry Safonov 
Signed-off-by: David S. Miller

Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net

2018-08-02T17:55:32+00:00

The BTF conflicts were simple overlapping changes.

The virtio_net conflict was an overlap of a fix of statistics counter,
happening alongisde a move over to a bonafide statistics structure
rather than counting value on the stack.

Signed-off-by: David S. Miller