In genl_register_family(), when idr_alloc() fails,
we forget to free the memory we possibly allocate for
family->attrbuf.
Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: 2ae0f17df1 ("genetlink: use idr to track families")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The rhashtable_walk_init function has been obsolete for more than
two years. This patch finally converts its last users over to
rhashtable_walk_enter and removes it.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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 <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 <jakub.kicinski@netronome.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 <dsahern@gmail.com>
Acked-by: Christian Brauner <christian@brauner.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 <dsahern@gmail.com>
Acked-by: Christian Brauner <christian@brauner.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 <zhangyu31@baidu.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: netdev@vger.kernel.org
Fairly-blamed-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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: 61f4b23769 ("netlink: Don't shift with UB on nlk->ngroups")
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: netdev@vger.kernel.org
Cc: stable@vger.kernel.org
Reported-and-Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 <davem@davemloft.net>
'protocol' is a user-controlled value, so sanitize it after the bounds
check to avoid using it for speculative out-of-bounds access to arrays
indexed by it.
This addresses the following accesses detected with the help of smatch:
* net/netlink/af_netlink.c:654 __netlink_create() warn: potential
spectre issue 'nlk_cb_mutex_keys' [w]
* net/netlink/af_netlink.c:654 __netlink_create() warn: potential
spectre issue 'nlk_cb_mutex_key_strings' [w]
* net/netlink/af_netlink.c:685 netlink_create() warn: potential spectre
issue 'nl_table' [w] (local cap)
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jeremy Cline <jcline@redhat.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On i386 nlk->ngroups might be 32 or 0. Which leads to UB, resulting in
hang during boot.
Check for 0 ngroups and use (unsigned long long) as a type to shift.
Fixes: 7acf9d4237 ("netlink: Do not subscribe to non-existent groups").
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make ABI more strict about subscribing to group > ngroups.
Code doesn't check for that and it looks bogus.
(one can subscribe to non-existing group)
Still, it's possible to bind() to all possible groups with (-1)
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: netdev@vger.kernel.org
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
->start() is called once when dump is being initialized, there is no
need to store it in netlink_cb.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The poll() changes were not well thought out, and completely
unexplained. They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.
Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead. That gets rid of one of the new indirections.
But that doesn't fix the new complexity that is completely unwarranted
for the regular case. The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.
[ This revert is a revert of about 30 different commits, not reverted
individually because that would just be unnecessarily messy - Linus ]
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull aio updates from Al Viro:
"Majority of AIO stuff this cycle. aio-fsync and aio-poll, mostly.
The only thing I'm holding back for a day or so is Adam's aio ioprio -
his last-minute fixup is trivial (missing stub in !CONFIG_BLOCK case),
but let it sit in -next for decency sake..."
* 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
aio: sanitize the limit checking in io_submit(2)
aio: fold do_io_submit() into callers
aio: shift copyin of iocb into io_submit_one()
aio_read_events_ring(): make a bit more readable
aio: all callers of aio_{read,write,fsync,poll} treat 0 and -EIOCBQUEUED the same way
aio: take list removal to (some) callers of aio_complete()
aio: add missing break for the IOCB_CMD_FDSYNC case
random: convert to ->poll_mask
timerfd: convert to ->poll_mask
eventfd: switch to ->poll_mask
pipe: convert to ->poll_mask
crypto: af_alg: convert to ->poll_mask
net/rxrpc: convert to ->poll_mask
net/iucv: convert to ->poll_mask
net/phonet: convert to ->poll_mask
net/nfc: convert to ->poll_mask
net/caif: convert to ->poll_mask
net/bluetooth: convert to ->poll_mask
net/sctp: convert to ->poll_mask
net/tipc: convert to ->poll_mask
...
Variants of proc_create{,_data} that directly take a struct seq_operations
and deal with network namespaces in ->open and ->release. All callers of
proc_create + seq_open_net converted over, and seq_{open,release}_net are
removed entirely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Making sure the headers line up properly with the actual value output of the command
`cat /proc/net/netlink`
Before the patch:
<sk Eth Pid Groups Rmem Wmem Dump Locks Drops Inode
<ffff8cd2c2f7b000 0 909 00000550 0 0 0 2 0 18946
After the patch:
>sk Eth Pid Groups Rmem Wmem Dump Locks Drops Inode
>0000000033203952 0 897 00000113 0 0 0 2 0 14906
Signed-off-by: Bo YU <tsu.yubo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Minor conflicts in drivers/net/ethernet/mellanox/mlx5/core/en_rep.c,
we had some overlapping changes:
1) In 'net' MLX5E_PARAMS_LOG_{SQ,RQ}_SIZE -->
MLX5E_REP_PARAMS_LOG_{SQ,RQ}_SIZE
2) In 'net-next' params->log_rq_size is renamed to be
params->log_rq_mtu_frames.
3) In 'net-next' params->hard_mtu is added.
Signed-off-by: David S. Miller <davem@davemloft.net>
Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
KMSAN reports use of uninitialized memory in the case when |alen| is
smaller than sizeof(struct sockaddr_nl), and therefore |nladdr| isn't
fully copied from the userspace.
Signed-off-by: Alexander Potapenko <glider@google.com>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fun set of conflict resolutions here...
For the mac80211 stuff, these were fortunately just parallel
adds. Trivially resolved.
In drivers/net/phy/phy.c we had a bug fix in 'net' that moved the
function phy_disable_interrupts() earlier in the file, whilst in
'net-next' the phy_error() call from this function was removed.
In net/ipv4/xfrm4_policy.c, David Ahern's changes to remove the
'rt_table_id' member of rtable collided with a bug fix in 'net' that
added a new struct member "rt_mtu_locked" which needs to be copied
over here.
The mlxsw driver conflict consisted of net-next separating
the span code and definitions into separate files, whilst
a 'net' bug fix made some changes to that moved code.
The mlx5 infiniband conflict resolution was quite non-trivial,
the RDMA tree's merge commit was used as a guide here, and
here are their notes:
====================
Due to bug fixes found by the syzkaller bot and taken into the for-rc
branch after development for the 4.17 merge window had already started
being taken into the for-next branch, there were fairly non-trivial
merge issues that would need to be resolved between the for-rc branch
and the for-next branch. This merge resolves those conflicts and
provides a unified base upon which ongoing development for 4.17 can
be based.
Conflicts:
drivers/infiniband/hw/mlx5/main.c - Commit 42cea83f95
(IB/mlx5: Fix cleanup order on unload) added to for-rc and
commit b5ca15ad7e (IB/mlx5: Add proper representors support)
add as part of the devel cycle both needed to modify the
init/de-init functions used by mlx5. To support the new
representors, the new functions added by the cleanup patch
needed to be made non-static, and the init/de-init list
added by the representors patch needed to be modified to
match the init/de-init list changes made by the cleanup
patch.
Updates:
drivers/infiniband/hw/mlx5/mlx5_ib.h - Update function
prototypes added by representors patch to reflect new function
names as changed by cleanup patch
drivers/infiniband/hw/mlx5/ib_rep.c - Update init/de-init
stage list to match new order from cleanup patch
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
nlmsg_multicast() consumes always the skb, thus the original skb must be
freed only when this function is called with a clone.
Fixes: cb9f7a9a5c ("netlink: ensure to loop over all netns in genlmsg_multicast_allns()")
Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Before, if cb->start() failed, the module reference would never be put,
because cb->cb_running is intentionally false at this point. Users are
generally annoyed by this because they can no longer unload modules that
leak references. Also, it may be possible to tediously wrap a reference
counter back to zero, especially since module.c still uses atomic_inc
instead of refcount_inc.
This patch expands the error path to simply call module_put if
cb->start() fails.
Fixes: 41c87425a1 ("netlink: do not set cb_running if dump's start() errs")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
These pernet_operations init just allocated net memory,
and they obviously can be executed in parallel in any
others.
v3: New
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This pernet_operations create and destroy net::genl_sock.
Foreign pernet_operations don't touch it.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The methods of netlink_net_ops create and destroy "netlink"
file, which are not interesting for foreigh pernet_operations.
So, netlink_net_ops may safely be made async.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Changes since v1:
Added changes in these files:
drivers/infiniband/hw/usnic/usnic_transport.c
drivers/staging/lustre/lnet/lnet/lib-socket.c
drivers/target/iscsi/iscsi_target_login.c
drivers/vhost/net.c
fs/dlm/lowcomms.c
fs/ocfs2/cluster/tcp.c
security/tomoyo/network.c
Before:
All these functions either return a negative error indicator,
or store length of sockaddr into "int *socklen" parameter
and return zero on success.
"int *socklen" parameter is awkward. For example, if caller does not
care, it still needs to provide on-stack storage for the value
it does not need.
None of the many FOO_getname() functions of various protocols
ever used old value of *socklen. They always just overwrite it.
This change drops this parameter, and makes all these functions, on success,
return length of sockaddr. It's always >= 0 and can be differentiated
from an error.
Tests in callers are changed from "if (err)" to "if (err < 0)", where needed.
rpc_sockname() lost "int buflen" parameter, since its only use was
to be passed to kernel_getsockname() as &buflen and subsequently
not used in any way.
Userspace API is not changed.
text data bss dec hex filename
30108430 2633624 873672 33615726 200ef6e vmlinux.before.o
30108109 2633612 873672 33615393 200ee21 vmlinux.o
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: David S. Miller <davem@davemloft.net>
CC: linux-kernel@vger.kernel.org
CC: netdev@vger.kernel.org
CC: linux-bluetooth@vger.kernel.org
CC: linux-decnet-user@lists.sourceforge.net
CC: linux-wireless@vger.kernel.org
CC: linux-rdma@vger.kernel.org
CC: linux-sctp@vger.kernel.org
CC: linux-nfs@vger.kernel.org
CC: linux-x25@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
Nowadays, nlmsg_multicast() returns only 0 or -ESRCH but this was not the
case when commit 134e63756d was pushed.
However, there was no reason to stop the loop if a netns does not have
listeners.
Returns -ESRCH only if there was no listeners in all netns.
To avoid having the same problem in the future, I didn't take the
assumption that nlmsg_multicast() returns only 0 or -ESRCH.
Fixes: 134e63756d ("genetlink: make netns aware")
CC: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The BPF verifier conflict was some minor contextual issue.
The TUN conflict was less trivial. Cong Wang fixed a memory leak of
tfile->tx_array in 'net'. This is an skb_array. But meanwhile in
net-next tun changed tfile->tx_arry into tfile->tx_ring which is a
ptr_ring.
Signed-off-by: David S. Miller <davem@davemloft.net>
Move up the extack reset/initialization in netlink_rcv_skb, so that
those 'goto ack' will not skip it. Otherwise, later on netlink_ack
may use the uninitialized extack and cause kernel crash.
Fixes: cbbdf8433a ("netlink: extack needs to be reset each time through loop")
Reported-by: syzbot+03bee3680a37466775e7@syzkaller.appspotmail.com
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
/proc has been ignoring struct file_operations::owner field for 10 years.
Specifically, it started with commit 786d7e1612
("Fix rmmod/read/write races in /proc entries"). Notice the chunk where
inode->i_fop is initialized with proxy struct file_operations for
regular files:
- if (de->proc_fops)
- inode->i_fop = de->proc_fops;
+ if (de->proc_fops) {
+ if (S_ISREG(inode->i_mode))
+ inode->i_fop = &proc_reg_file_ops;
+ else
+ inode->i_fop = de->proc_fops;
+ }
VFS stopped pinning module at this point.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
syzbot triggered the WARN_ON in netlink_ack testing the bad_attr value.
The problem is that netlink_rcv_skb loops over the skb repeatedly invoking
the callback and without resetting the extack leaving potentially stale
data. Initializing each time through avoids the WARN_ON.
Fixes: 2d4bc93368 ("netlink: extended ACK reporting")
Reported-by: syzbot+315fa6766d0f7c359327@syzkaller.appspotmail.com
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Three sets of overlapping changes, two in the packet scheduler
and one in the meson-gxl PHY driver.
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, a nlmon link inside a child namespace can observe systemwide
netlink activity. Filter the traffic so that nlmon can only sniff
netlink messages from its own netns.
Test case:
vpnns -- bash -c "ip link add nlmon0 type nlmon; \
ip link set nlmon0 up; \
tcpdump -i nlmon0 -q -w /tmp/nlmon.pcap -U" &
sudo ip xfrm state add src 10.1.1.1 dst 10.1.1.2 proto esp \
spi 0x1 mode transport \
auth sha1 0x6162633132330000000000000000000000000000 \
enc aes 0x00000000000000000000000000000000
grep --binary abc123 /tmp/nlmon.pcap
Signed-off-by: Kevin Cernekee <cernekee@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Both netlink_add_tap() and netlink_remove_tap() are
called in process context, no need to bother spinlock.
Note, in fact, currently we always hold RTNL when calling
these two functions, so we don't need any other lock at
all, but keeping this lock doesn't harm anything.
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
nlmon device is not supposed to capture netlink events from
other netns, so instead of filtering events, we can simply
make netlink tap itself per netns.
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Kevin Cernekee <cernekee@chromium.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Most callers of rhashtable_walk_start don't care about a resize event
which is indicated by a return value of -EAGAIN. So calls to
rhashtable_walk_start are wrapped wih code to ignore -EAGAIN. Something
like this is common:
ret = rhashtable_walk_start(rhiter);
if (ret && ret != -EAGAIN)
goto out;
Since zero and -EAGAIN are the only possible return values from the
function this check is pointless. The condition never evaluates to true.
This patch changes rhashtable_walk_start to return void. This simplifies
code for the callers that ignore -EAGAIN. For the few cases where the
caller cares about the resize event, particularly where the table can be
walked in mulitple parts for netlink or seq file dump, the function
rhashtable_walk_start_check has been added that returns -EAGAIN on a
resize event.
Signed-off-by: Tom Herbert <tom@quantonium.net>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
netlink_skb_destructor() is actually defined before the first usage
in the file, so remove the unnecessary forward declaration.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The way people generally use netlink_dump is that they fill in the skb
as much as possible, breaking when nla_put returns an error. Then, they
get called again and start filling out the next skb, and again, and so
forth. The mechanism at work here is the ability for the iterative
dumping function to detect when the skb is filled up and not fill it
past the brim, waiting for a fresh skb for the rest of the data.
However, if the attributes are small and nicely packed, it is possible
that a dump callback function successfully fills in attributes until the
skb is of size 4080 (libmnl's default page-sized receive buffer size).
The dump function completes, satisfied, and then, if it happens to be
that this is actually the last skb, and no further ones are to be sent,
then netlink_dump will add on the NLMSG_DONE part:
nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI);
It is very important that netlink_dump does this, of course. However, in
this example, that call to nlmsg_put_answer will fail, because the
previous filling by the dump function did not leave it enough room. And
how could it possibly have done so? All of the nla_put variety of
functions simply check to see if the skb has enough tailroom,
independent of the context it is in.
In order to keep the important assumptions of all netlink dump users, it
is therefore important to give them an skb that has this end part of the
tail already reserved, so that the call to nlmsg_put_answer does not
fail. Otherwise, library authors are forced to find some bizarre sized
receive buffer that has a large modulo relative to the common sizes of
messages received, which is ugly and buggy.
This patch thus saves the NLMSG_DONE for an additional message, for the
case that things are dangerously close to the brim. This requires
keeping track of the errno from ->dump() across calls.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Files removed in 'net-next' had their license header updated
in 'net'. We take the remove from 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The NLMSGERR API already carries data (eg, a cookie) on the success path.
Allow a message string to be returned as well.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
YueHaibing