Commit Graph

638 Commits

Author SHA1 Message Date
Eric Dumazet
7707a4d01a netlink: annotate data races around nlk->bound
While existing code is correct, KCSAN is reporting
a data-race in netlink_insert / netlink_sendmsg [1]

It is correct to read nlk->bound without a lock, as netlink_autobind()
will acquire all needed locks.

[1]
BUG: KCSAN: data-race in netlink_insert / netlink_sendmsg

write to 0xffff8881031c8b30 of 1 bytes by task 18752 on cpu 0:
 netlink_insert+0x5cc/0x7f0 net/netlink/af_netlink.c:597
 netlink_autobind+0xa9/0x150 net/netlink/af_netlink.c:842
 netlink_sendmsg+0x479/0x7c0 net/netlink/af_netlink.c:1892
 sock_sendmsg_nosec net/socket.c:703 [inline]
 sock_sendmsg net/socket.c:723 [inline]
 ____sys_sendmsg+0x360/0x4d0 net/socket.c:2392
 ___sys_sendmsg net/socket.c:2446 [inline]
 __sys_sendmsg+0x1ed/0x270 net/socket.c:2475
 __do_sys_sendmsg net/socket.c:2484 [inline]
 __se_sys_sendmsg net/socket.c:2482 [inline]
 __x64_sys_sendmsg+0x42/0x50 net/socket.c:2482
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881031c8b30 of 1 bytes by task 18751 on cpu 1:
 netlink_sendmsg+0x270/0x7c0 net/netlink/af_netlink.c:1891
 sock_sendmsg_nosec net/socket.c:703 [inline]
 sock_sendmsg net/socket.c:723 [inline]
 __sys_sendto+0x2a8/0x370 net/socket.c:2019
 __do_sys_sendto net/socket.c:2031 [inline]
 __se_sys_sendto net/socket.c:2027 [inline]
 __x64_sys_sendto+0x74/0x90 net/socket.c:2027
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 18751 Comm: syz-executor.0 Not tainted 5.14.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: da314c9923 ("netlink: Replace rhash_portid with bound")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-05 13:11:09 +01:00
Yajun Deng
bc83052561 net: netlink: Remove unused function
lockdep_genl_is_held() and its caller arm not used now, just remove them.

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Link: https://lore.kernel.org/r/20210729074854.8968-1-yajun.deng@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-30 18:35:47 +02:00
Yajun Deng
f9b282b36d net: netlink: add the case when nlh is NULL
Add the case when nlh is NULL in nlmsg_report(),
so that the caller doesn't need to deal with this case.

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-27 11:43:50 +01:00
Yajun Deng
fef773fc81 netlink: Deal with ESRCH error in nlmsg_notify()
Yonghong Song report:
The bpf selftest tc_bpf failed with latest bpf-next.
The following is the command to run and the result:
$ ./test_progs -n 132
[   40.947571] bpf_testmod: loading out-of-tree module taints kernel.
test_tc_bpf:PASS:test_tc_bpf__open_and_load 0 nsec
test_tc_bpf:PASS:bpf_tc_hook_create(BPF_TC_INGRESS) 0 nsec
test_tc_bpf:PASS:bpf_tc_hook_create invalid hook.attach_point 0 nsec
test_tc_bpf_basic:PASS:bpf_obj_get_info_by_fd 0 nsec
test_tc_bpf_basic:PASS:bpf_tc_attach 0 nsec
test_tc_bpf_basic:PASS:handle set 0 nsec
test_tc_bpf_basic:PASS:priority set 0 nsec
test_tc_bpf_basic:PASS:prog_id set 0 nsec
test_tc_bpf_basic:PASS:bpf_tc_attach replace mode 0 nsec
test_tc_bpf_basic:PASS:bpf_tc_query 0 nsec
test_tc_bpf_basic:PASS:handle set 0 nsec
test_tc_bpf_basic:PASS:priority set 0 nsec
test_tc_bpf_basic:PASS:prog_id set 0 nsec
libbpf: Kernel error message: Failed to send filter delete notification
test_tc_bpf_basic:FAIL:bpf_tc_detach unexpected error: -3 (errno 3)
test_tc_bpf:FAIL:test_tc_internal ingress unexpected error: -3 (errno 3)

The failure seems due to the commit
    cfdf0d9ae7 ("rtnetlink: use nlmsg_notify() in rtnetlink_send()")

Deal with ESRCH error in nlmsg_notify() even the report variable is zero.

Reported-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Link: https://lore.kernel.org/r/20210719051816.11762-1-yajun.deng@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-20 11:45:09 +02:00
Yajun Deng
01757f536a net: Use nlmsg_unicast() instead of netlink_unicast()
It has 'if (err >0 )' statement in nlmsg_unicast(), so use nlmsg_unicast()
instead of netlink_unicast(), this looks more concise.

v2: remove the change in netfilter.

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-13 09:28:29 -07:00
Alexander Aring
e3ae2365ef net: sock: introduce sk_error_report
This patch introduces a function wrapper to call the sk_error_report
callback. That will prepare to add additional handling whenever
sk_error_report is called, for example to trace socket errors.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29 11:28:21 -07:00
Johannes Berg
1d482e666b netlink: disable IRQs for netlink_lock_table()
Syzbot reports that in mac80211 we have a potential deadlock
between our "local->stop_queue_reasons_lock" (spinlock) and
netlink's nl_table_lock (rwlock). This is because there's at
least one situation in which we might try to send a netlink
message with this spinlock held while it is also possible to
take the spinlock from a hardirq context, resulting in the
following deadlock scenario reported by lockdep:

       CPU0                    CPU1
       ----                    ----
  lock(nl_table_lock);
                               local_irq_disable();
                               lock(&local->queue_stop_reason_lock);
                               lock(nl_table_lock);
  <Interrupt>
    lock(&local->queue_stop_reason_lock);

This seems valid, we can take the queue_stop_reason_lock in
any kind of context ("CPU0"), and call ieee80211_report_ack_skb()
with the spinlock held and IRQs disabled ("CPU1") in some
code path (ieee80211_do_stop() via ieee80211_free_txskb()).

Short of disallowing netlink use in scenarios like these
(which would be rather complex in mac80211's case due to
the deep callchain), it seems the only fix for this is to
disable IRQs while nl_table_lock is held to avoid hitting
this scenario, this disallows the "CPU0" portion of the
reported deadlock.

Note that the writer side (netlink_table_grab()) already
disables IRQs for this lock.

Unfortunately though, this seems like a huge hammer, and
maybe the whole netlink table locking should be reworked.

Reported-by: syzbot+69ff9dff50dcfe14ddd4@syzkaller.appspotmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-17 15:31:03 -07:00
Florian Westphal
f2764bd4f6 netlink: don't call ->netlink_bind with table lock held
When I added support to allow generic netlink multicast groups to be
restricted to subscribers with CAP_NET_ADMIN I was unaware that a
genl_bind implementation already existed in the past.

It was reverted due to ABBA deadlock:

1. ->netlink_bind gets called with the table lock held.
2. genetlink bind callback is invoked, it grabs the genl lock.

But when a new genl subsystem is (un)registered, these two locks are
taken in reverse order.

One solution would be to revert again and add a comment in genl
referring 1e82a62fec, "genetlink: remove genl_bind").

This would need a second change in mptcp to not expose the raw token
value anymore, e.g.  by hashing the token with a secret key so userspace
can still associate subflow events with the correct mptcp connection.

However, Paolo Abeni reminded me to double-check why the netlink table is
locked in the first place.

I can't find one.  netlink_bind() is already called without this lock
when userspace joins a group via NETLINK_ADD_MEMBERSHIP setsockopt.
Same holds for the netlink_unbind operation.

Digging through the history, commit f773608026
("netlink: access nlk groups safely in netlink bind and getname")
expanded the lock scope.

commit 3a20773bee ("net: netlink: cap max groups which will be considered in netlink_bind()")
... removed the nlk->ngroups access that the lock scope
extension was all about.

Reduce the lock scope again and always call ->netlink_bind without
the table lock.

The Fixes tag should be vs. the patch mentioned in the link below,
but that one got squash-merged into the patch that came earlier in the
series.

Fixes: 4d54cc3211 ("mptcp: avoid lock_fast usage in accept path")
Link: https://lore.kernel.org/mptcp/20210213000001.379332-8-mathew.j.martineau@linux.intel.com/T/#u
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Xin Long <lucien.xin@gmail.com>
Cc: Johannes Berg <johannes.berg@intel.com>
Cc: Sean Tranchetti <stranche@codeaurora.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 17:01:04 -07:00
Florian Westphal
4d54cc3211 mptcp: avoid lock_fast usage in accept path
Once event support is added this may need to allocate memory while msk
lock is held with softirqs disabled.

Not using lock_fast also allows to do the allocation with GFP_KERNEL.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-12 16:31:46 -08:00
Marcelo Ricardo Leitner
7e3ce05e7f netlink: add tracepoint at NL_SET_ERR_MSG
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 <marcelo.leitner@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/4546b63e67b2989789d146498b13cc09e1fdc543.1612403190.git.marcelo.leitner@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-02-04 18:05:59 -08:00
Johannes Berg
44f3625bc6 netlink: export policy in extended ACK
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 <kuba@kernel.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-09 20:22:32 -07:00
Johannes Berg
d2681e93b0 netlink: policy: refactor per-attr policy writing
Refactor the per-attribute policy writing into a new
helper function, to be used later for dumping out the
policy of a rejected attribute.

v2:
 - fix some indentation
v3:
 - change variable order in netlink_policy_dump_write()

Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-09 20:22:31 -07:00
Jakub Kicinski
bdbb4e29df netlink: add mask validation
We don't have good validation policy for existing unsigned int attrs
which serve as flags (for new ones we could use NLA_BITFIELD32).
With increased use of policy dumping having the validation be
expressed as part of the policy is important. Add validation
policy in form of a mask of supported/valid bits.

Support u64 in the uAPI to be future-proof, but really for now
the embedded mask member can only hold 32 bits, so anything with
bit 32+ set will always fail validation.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-06 06:25:55 -07:00
Jakub Kicinski
e992a6eda9 genetlink: allow dumping command-specific policy
Right now CTRL_CMD_GETPOLICY can only dump the family-wide
policy. Support dumping policy of a specific op.

v3:
 - rebase after per-op policy export and handle that
v2:
 - make cmd U32, just in case.
v1:
 - don't echo op in the output in a naive way, this should
   make it cleaner to extend the output format for dumping
   policies for all the commands at once in the future.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20201001225933.1373426-11-kuba@kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-03 14:18:29 -07:00
Johannes Berg
50a896cf2d genetlink: properly support per-op policy dumping
Add support for per-op policy dumping. The data is pretty much
as before, except that now the assumption that the policy with
index 0 is "the" policy no longer holds - you now need to look
at the new CTRL_ATTR_OP_POLICY attribute which is a nested attr
(indexed by op) containing attributes for do and dump policies.

When a single op is requested, the CTRL_ATTR_OP_POLICY will be
added in the same way, since do and dump policies may differ.

v2:
 - conditionally advertise per-command policies only if there
   actually is a policy being used for the do/dump and it's
   present at all

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-03 14:18:29 -07:00
Johannes Berg
aa85ee5f95 genetlink: factor skb preparation out of ctrl_dumppolicy()
We'll need this later for the per-op policy index dump.

Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-03 14:18:29 -07:00
Johannes Berg
04a351a62b netlink: rework policy dump to support multiple policies
Rework the policy dump code a bit to support adding multiple
policies to a single dump, in order to e.g. support per-op
policies in generic netlink.

v2:
 - move kernel-doc to implementation [Jakub]
 - squash the first patch to not flip-flop on the prototype
   [Jakub]
 - merge netlink_policy_dump_get_policy_idx() with the old
   get_policy_idx() we already had
 - rebase without Jakub's patch to have per-op dump

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-03 14:18:29 -07:00
Johannes Berg
899b07c578 netlink: compare policy more accurately
The maxtype is really an integral part of the policy, and while we
haven't gotten into a situation yet where this happens, it seems
that some developer might eventually have two places pointing to
identical policies, with different maxattr to exclude some attrs
in one of the places.

Even if not, it's really the right thing to compare both since the
two data items fundamentally belong together.

v2:
 - also do the proper comparison in get_policy_idx()

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-03 14:18:29 -07:00
Jakub Kicinski
a4bb4f5fc8 genetlink: switch control commands to per-op policies
In preparation for adding a new attribute to CTRL_CMD_GETPOLICY
split the policies for getpolicy and getfamily apart.

This will cause a slight user-visible change in that dumping
the policies will switch from per family to per op, but
supposedly sniffer-type applications (which are the main use
case for policy dumping thus far) should support both, anyway.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02 19:11:12 -07:00
Jakub Kicinski
8e1ed28fd8 genetlink: use parsed attrs in dumppolicy
Attributes are already parsed based on the policy specified
in the family and ready-to-use in info->attrs. No need to
call genlmsg_parse() again.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02 19:11:12 -07:00
Jakub Kicinski
48526a0f4c genetlink: bring back per op policy
Add policy to the struct genl_ops structure, this time
with maxattr, so it can be used properly.

Propagate .policy and .maxattr from the family
in genl_get_cmd() if needed, this way the rest of the
code does not have to worry if the policy is per op
or global.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02 19:11:12 -07:00
Jakub Kicinski
78ade619c1 genetlink: use .start callback for dumppolicy
The structure of ctrl_dumppolicy() is clearly split into
init and dumping. Move the init to a .start callback
for clarity, it's a more idiomatic netlink dump code structure.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02 19:11:12 -07:00
Jakub Kicinski
adc848450f genetlink: add a structure for dump state
Whenever netlink dump uses more than 2 cb->args[] entries
code gets hard to read. We're about to add more state to
ctrl_dumppolicy() so create a structure.

Since the structure is typed and clearly named we can remove
the local fam_id variable and use ctx->fam_id directly.

v3:
 - rebase onto explicit free fix
v1:
 - s/nl_policy_dump/netlink_policy_dump_state/
 - forward declare struct netlink_policy_dump_state,
   and move from passing unsigned long to actual pointer type
 - add build bug on
 - u16 fam_id
 - s/args/ctx/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02 19:11:12 -07:00
Jakub Kicinski
0b588afdd1 genetlink: add small version of ops
We want to add maxattr and policy back to genl_ops, to enable
dumping per command policy to user space. This, however, would
cause bloat for all the families with global policies. Introduce
smaller version of ops (half the size of genl_ops). Translate
these smaller ops into a full blown struct before use in the
core.

v1:
 - use struct assignment
 - put a full copy of the op in struct genl_dumpit_info
 - s/light/small/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02 19:11:11 -07:00
David S. Miller
c16bcd70a1 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next
Steffen Klassert says:

====================
pull request (net-next): ipsec-next 2020-10-02

1) Add a full xfrm compatible layer for 32-bit applications on
   64-bit kernels. From Dmitry Safonov.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02 13:16:15 -07:00
Johannes Berg
949ca6b82e netlink: fix policy dump leak
[ Upstream commit a95bc734e6 ]

If userspace doesn't complete the policy dump, we leak the
allocated state. Fix this.

Fixes: d07dcf9aad ("netlink: add infrastructure to expose policies to userspace")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02 13:07:42 -07:00
Dmitry Safonov
e11eb32de3 netlink/compat: Append NLMSG_DONE/extack to frag_list
Modules those use netlink may supply a 2nd skb, (via frag_list)
that contains an alternative data set meant for applications
using 32bit compatibility mode.

In such a case, netlink_recvmsg will use this 2nd skb instead of the
original one.

Without this patch, such compat applications will retrieve
all netlink dump data, but will then get an unexpected EOF.

Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2020-09-24 08:53:03 +02:00
Yang Yingliang
4d11af5d00 netlink: add spaces around '&' in netlink_recv/sendmsg()
It's hard to read the code without spaces around '&',
for better reading, add spaces around '&'.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-17 16:53:47 -07:00
Jakub Kicinski
44a8c4f33c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
We got slightly different patches removing a double word
in a comment in net/ipv4/raw.c - picked the version from net.

Simple conflict in drivers/net/ethernet/ibm/ibmvnic.c. Use cached
values instead of VNIC login response buffer (following what
commit 507ebe6444 ("ibmvnic: Fix use-after-free of VNIC login
response buffer") did).

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-04 21:28:59 -07:00
Linus Torvalds
3e8d3bdc2a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Use netif_rx_ni() when necessary in batman-adv stack, from Jussi
    Kivilinna.

 2) Fix loss of RTT samples in rxrpc, from David Howells.

 3) Memory leak in hns_nic_dev_probe(), from Dignhao Liu.

 4) ravb module cannot be unloaded, fix from Yuusuke Ashizuka.

 5) We disable BH for too lokng in sctp_get_port_local(), add a
    cond_resched() here as well, from Xin Long.

 6) Fix memory leak in st95hf_in_send_cmd, from Dinghao Liu.

 7) Out of bound access in bpf_raw_tp_link_fill_link_info(), from
    Yonghong Song.

 8) Missing of_node_put() in mt7530 DSA driver, from Sumera
    Priyadarsini.

 9) Fix crash in bnxt_fw_reset_task(), from Michael Chan.

10) Fix geneve tunnel checksumming bug in hns3, from Yi Li.

11) Memory leak in rxkad_verify_response, from Dinghao Liu.

12) In tipc, don't use smp_processor_id() in preemptible context. From
    Tuong Lien.

13) Fix signedness issue in mlx4 memory allocation, from Shung-Hsi Yu.

14) Missing clk_disable_prepare() in gemini driver, from Dan Carpenter.

15) Fix ABI mismatch between driver and firmware in nfp, from Louis
    Peens.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (110 commits)
  net/smc: fix sock refcounting in case of termination
  net/smc: reset sndbuf_desc if freed
  net/smc: set rx_off for SMCR explicitly
  net/smc: fix toleration of fake add_link messages
  tg3: Fix soft lockup when tg3_reset_task() fails.
  doc: net: dsa: Fix typo in config code sample
  net: dp83867: Fix WoL SecureOn password
  nfp: flower: fix ABI mismatch between driver and firmware
  tipc: fix shutdown() of connectionless socket
  ipv6: Fix sysctl max for fib_multipath_hash_policy
  drivers/net/wan/hdlc: Change the default of hard_header_len to 0
  net: gemini: Fix another missing clk_disable_unprepare() in probe
  net: bcmgenet: fix mask check in bcmgenet_validate_flow()
  amd-xgbe: Add support for new port mode
  net: usb: dm9601: Add USB ID of Keenetic Plus DSL
  vhost: fix typo in error message
  net: ethernet: mlx4: Fix memory allocation in mlx4_buddy_init()
  pktgen: fix error message with wrong function name
  net: ethernet: ti: am65-cpsw: fix rmii 100Mbit link mode
  cxgb4: fix thermal zone device registration
  ...
2020-09-03 18:50:48 -07:00
Johannes Berg
c30a3c957c netlink: policy: correct validation type check
In the policy export for binary attributes I erroneously used
a != NLA_VALIDATE_NONE comparison instead of checking for the
two possible values, which meant that if a validation function
pointer ended up aliasing the min/max as negatives, we'd hit
a warning in nla_get_range_unsigned().

Fix this to correctly check for only the two types that should
be handled here, i.e. range with or without warn-too-long.

Reported-by: syzbot+353df1490da781637624@syzkaller.appspotmail.com
Fixes: 8aa26c575f ("netlink: make NLA_BINARY validation more flexible")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-31 12:01:15 -07:00
zhudi
174bce38ca netlink: fix a data race in netlink_rcv_wake()
The data races were reported by KCSAN:
BUG: KCSAN: data-race in netlink_recvmsg / skb_queue_tail

write (marked) to 0xffff8c0986e5a8c8 of 8 bytes by interrupt on cpu 3:
 skb_queue_tail+0xcc/0x120
 __netlink_sendskb+0x55/0x80
 netlink_broadcast_filtered+0x465/0x7e0
 nlmsg_notify+0x8f/0x120
 rtnl_notify+0x8e/0xb0
 __neigh_notify+0xf2/0x120
 neigh_update+0x927/0xde0
 arp_process+0x8a3/0xf50
 arp_rcv+0x27c/0x3b0
 __netif_receive_skb_core+0x181c/0x1840
 __netif_receive_skb+0x38/0xf0
 netif_receive_skb_internal+0x77/0x1c0
 napi_gro_receive+0x1bd/0x1f0
 e1000_clean_rx_irq+0x538/0xb20 [e1000]
 e1000_clean+0x5e4/0x1340 [e1000]
 net_rx_action+0x310/0x9d0
 __do_softirq+0xe8/0x308
 irq_exit+0x109/0x110
 do_IRQ+0x7f/0xe0
 ret_from_intr+0x0/0x1d
 0xffffffffffffffff

read to 0xffff8c0986e5a8c8 of 8 bytes by task 1463 on cpu 0:
 netlink_recvmsg+0x40b/0x820
 sock_recvmsg+0xc9/0xd0
 ___sys_recvmsg+0x1a4/0x3b0
 __sys_recvmsg+0x86/0x120
 __x64_sys_recvmsg+0x52/0x70
 do_syscall_64+0xb5/0x360
 entry_SYSCALL_64_after_hwframe+0x65/0xca
 0xffffffffffffffff

Since the write is under sk_receive_queue->lock but the read
is done as lockless. so fix it by using skb_queue_empty_lockless()
instead of skb_queue_empty() for the read in netlink_rcv_wake()

Signed-off-by: zhudi <zhudi21@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-28 06:51:11 -07:00
Randy Dunlap
8540591885 net: netlink: delete repeated words
Drop duplicated words in net/netlink/.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-24 17:31:20 -07:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
David S. Miller
7611cbb900 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-08-23 11:48:27 -07:00
Johannes Berg
d1fb555929 netlink: fix state reallocation in policy export
Evidently, when I did this previously, we didn't have more than
10 policies and didn't run into the reallocation path, because
it's missing a memset() for the unused policies. Fix that.

Fixes: d07dcf9aad ("netlink: add infrastructure to expose policies to userspace")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-19 15:39:36 -07:00
Johannes Berg
8aa26c575f netlink: make NLA_BINARY validation more flexible
Add range validation for NLA_BINARY, allowing validation of any
combination of combination minimum or maximum lengths, using the
existing NLA_POLICY_RANGE()/NLA_POLICY_FULL_RANGE() macros, just
like for integers where the value is checked.

Also make NLA_POLICY_EXACT_LEN(), NLA_POLICY_EXACT_LEN_WARN()
and NLA_POLICY_MIN_LEN() special cases of this, removing the old
types NLA_EXACT_LEN and NLA_MIN_LEN.

This allows us to save some code where both minimum and maximum
lengths are requires, currently the policy only allows maximum
(NLA_BINARY), minimum (NLA_MIN_LEN) or exact (NLA_EXACT_LEN), so
a range of lengths cannot be accepted and must be checked by the
code that consumes the attributes later.

Also, this allows advertising the correct ranges in the policy
export to userspace. Here, NLA_MIN_LEN and NLA_EXACT_LEN already
were special cases of NLA_BINARY with min and min/max length
respectively.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-18 12:28:45 -07:00
Linus Torvalds
96e3f3c16b - Add support to enable/disable the thermal zones resulting on core code and
drivers cleanup (Andrzej Pietrasiewicz)
 
 - Add generic netlink support for userspace notifications: events, temperature
   and discovery commands (Daniel Lezcano)
 
 - Fix redundant initialization for a ret variable (Colin Ian King)
 
 - Remove the clock cooling code as it is used nowhere (Amit Kucheria)
 
 - Add the rcar_gen3_thermal's r8a774e1 support (Marian-Cristian Rotariu)
 
 - Replace all references to thermal.txt in the documentation to the
   corresponding yaml files (Amit Kucheria)
 
 - Add maintainer entry for the IPA (Lukasz Luba)
 
 - Add support for MSM8939 for the tsens (Shawn Guo)
 
 - Update power allocator and devfreq cooling to SPDX licensing (Lukasz Luba)
 
 - Add Cannon Lake Low Power PCH support (Sumeet Pawnikar)
 
 - Add tsensor support for V2 mediatek thermal system (Henry Yen)
 
 - Fix thermal zone lookup by ID for the core code (Thierry Reding)
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Merge tag 'thermal-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux

Pull thermal updates from Daniel Lezcano:

 - Add support to enable/disable the thermal zones resulting on core
   code and drivers cleanup (Andrzej Pietrasiewicz)

 - Add generic netlink support for userspace notifications: events,
   temperature and discovery commands (Daniel Lezcano)

 - Fix redundant initialization for a ret variable (Colin Ian King)

 - Remove the clock cooling code as it is used nowhere (Amit Kucheria)

 - Add the rcar_gen3_thermal's r8a774e1 support (Marian-Cristian
   Rotariu)

 - Replace all references to thermal.txt in the documentation to the
   corresponding yaml files (Amit Kucheria)

 - Add maintainer entry for the IPA (Lukasz Luba)

 - Add support for MSM8939 for the tsens (Shawn Guo)

 - Update power allocator and devfreq cooling to SPDX licensing (Lukasz
   Luba)

 - Add Cannon Lake Low Power PCH support (Sumeet Pawnikar)

 - Add tsensor support for V2 mediatek thermal system (Henry Yen)

 - Fix thermal zone lookup by ID for the core code (Thierry Reding)

* tag 'thermal-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux: (40 commits)
  thermal: intel: intel_pch_thermal: Add Cannon Lake Low Power PCH support
  thermal: mediatek: Add tsensor support for V2 thermal system
  thermal: mediatek: Prepare to add support for other platforms
  thermal: Update power allocator and devfreq cooling to SPDX licensing
  MAINTAINERS: update entry to thermal governors file name prefixing
  thermal: core: Add thermal zone enable/disable notification
  thermal: qcom: tsens-v0_1: Add support for MSM8939
  dt-bindings: tsens: qcom: Document MSM8939 compatible
  thermal: core: Fix thermal zone lookup by ID
  thermal: int340x: processor_thermal: fix: update Jasper Lake PCI id
  thermal: imx8mm: Support module autoloading
  thermal: ti-soc-thermal: Fix reversed condition in ti_thermal_expose_sensor()
  MAINTAINERS: Add maintenance information for IPA
  thermal: rcar_gen3_thermal: Do not shadow thcode variable
  dt-bindings: thermal: Get rid of thermal.txt and replace references
  thermal: core: Move initialization after core initcall
  thermal: netlink: Improve the initcall ordering
  net: genetlink: Move initialization to core_initcall
  thermal: rcar_gen3_thermal: Add r8a774e1 support
  thermal/drivers/clock_cooling: Remove clock_cooling code
  ...
2020-08-06 18:10:55 -07:00
Yonghong Song
14fc6bd6b7 bpf: Refactor bpf_iter_reg to have separate seq_info member
There is no functionality change for this patch.
Struct bpf_iter_reg is used to register a bpf_iter target,
which includes information for both prog_load, link_create
and seq_file creation.

This patch puts fields related seq_file creation into
a different structure. This will be useful for map
elements iterator where one iterator covers different
map types and different map types may have different
seq_ops, init/fini private_data function and
private_data size.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184109.590030-1-yhs@fb.com
2020-07-25 20:16:32 -07:00
Christoph Hellwig
a7b75c5a8c net: pass a sockptr_t into ->setsockopt
Rework the remaining setsockopt code to pass a sockptr_t instead of a
plain user pointer.  This removes the last remaining set_fs(KERNEL_DS)
outside of architecture specific code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154]
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24 15:41:54 -07:00
Yonghong Song
951cf368bc bpf: net: Use precomputed btf_id for bpf iterators
One additional field btf_id is added to struct
bpf_ctx_arg_aux to store the precomputed btf_ids.
The btf_id is computed at build time with
BTF_ID_LIST or BTF_ID_LIST_GLOBAL macro definitions.
All existing bpf iterators are changed to used
pre-compute btf_ids.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200720163403.1393551-1-yhs@fb.com
2020-07-21 13:26:26 -07:00
Daniel Lezcano
c62e7ac395 net: genetlink: Move initialization to core_initcall
The generic netlink is initialized far after the netlink protocol
itself at subsys_initcall. The devlink is initialized at the same
level, but after, as shown by a disassembly of the vmlinux:

[ ... ]
374 ffff8000115f22c0 <__initcall_devlink_init4>:
375 ffff8000115f22c4 <__initcall_genl_init4>:
[ ... ]

The function devlink_init() calls genl_register_family() before the
generic netlink subsystem is initialized.

As the generic netlink initcall level is set since 2005, it seems that
was not a problem, but now we have the thermal framework initialized
at the core_initcall level which creates the generic netlink family
and sends a notification which leads to a subtle memory corruption
only detectable when the CONFIG_INIT_ON_ALLOC_DEFAULT_ON option is set
with the earlycon at init time.

The thermal framework needs to be initialized early in order to begin
the mitigation as soon as possible. Moving it to postcore_initcall is
acceptable.

This patch changes the initialization level for the generic netlink
family to the core_initcall and comes after the netlink protocol
initialization.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Link: https://lore.kernel.org/r/20200715074120.8768-1-daniel.lezcano@linaro.org
2020-07-21 10:40:08 +02:00
Sean Tranchetti
1e82a62fec genetlink: remove genl_bind
A potential deadlock can occur during registering or unregistering a
new generic netlink family between the main nl_table_lock and the
cb_lock where each thread wants the lock held by the other, as
demonstrated below.

1) Thread 1 is performing a netlink_bind() operation on a socket. As part
   of this call, it will call netlink_lock_table(), incrementing the
   nl_table_users count to 1.
2) Thread 2 is registering (or unregistering) a genl_family via the
   genl_(un)register_family() API. The cb_lock semaphore will be taken for
   writing.
3) Thread 1 will call genl_bind() as part of the bind operation to handle
   subscribing to GENL multicast groups at the request of the user. It will
   attempt to take the cb_lock semaphore for reading, but it will fail and
   be scheduled away, waiting for Thread 2 to finish the write.
4) Thread 2 will call netlink_table_grab() during the (un)registration
   call. However, as Thread 1 has incremented nl_table_users, it will not
   be able to proceed, and both threads will be stuck waiting for the
   other.

genl_bind() is a noop, unless a genl_family implements the mcast_bind()
function to handle setting up family-specific multicast operations. Since
no one in-tree uses this functionality as Cong pointed out, simply removing
the genl_bind() function will remove the possibility for deadlock, as there
is no attempt by Thread 1 above to take the cb_lock semaphore.

Fixes: c380d9a7af ("genetlink: pass multicast bind/unbind to families")
Suggested-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Johannes Berg <johannes.berg@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Sean Tranchetti <stranche@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-01 15:49:11 -07:00
Cong Wang
bf64ff4c2a genetlink: get rid of family->attrbuf
genl_family_rcv_msg_attrs_parse() reuses the global family->attrbuf
when family->parallel_ops is false. However, family->attrbuf is not
protected by any lock on the genl_family_rcv_msg_doit() code path.

This leads to several different consequences, one of them is UAF,
like the following:

genl_family_rcv_msg_doit():		genl_start():
					  genl_family_rcv_msg_attrs_parse()
					    attrbuf = family->attrbuf
					    __nlmsg_parse(attrbuf);
  genl_family_rcv_msg_attrs_parse()
    attrbuf = family->attrbuf
    __nlmsg_parse(attrbuf);
					  info->attrs = attrs;
					  cb->data = info;

netlink_unicast_kernel():
 consume_skb()
					genl_lock_dumpit():
					  genl_dumpit_info(cb)->attrs

Note family->attrbuf is an array of pointers to the skb data, once
the skb is freed, any dereference of family->attrbuf will be a UAF.

Maybe we could serialize the family->attrbuf with genl_mutex too, but
that would make the locking more complicated. Instead, we can just get
rid of family->attrbuf and always allocate attrbuf from heap like the
family->parallel_ops==true code path. This may add some performance
overhead but comparing with taking the global genl_mutex, it still
looks better.

Fixes: 75cdbdd089 ("net: ieee802154: have genetlink code to parse the attrs during dumpit")
Fixes: 057af70713 ("net: tipc: have genetlink code to parse the attrs during dumpit")
Reported-and-tested-by: syzbot+3039ddf6d7b13daf3787@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+80cad1e3cb4c41cde6ff@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+736bcbcb11b60d0c0792@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+520f8704db2b68091d44@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+c96e4dfb32f8987fdeed@syzkaller.appspotmail.com
Cc: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-29 17:15:57 -07:00
Linus Torvalds
96144c58ab Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Fix cfg80211 deadlock, from Johannes Berg.

 2) RXRPC fails to send norigications, from David Howells.

 3) MPTCP RM_ADDR parsing has an off by one pointer error, fix from
    Geliang Tang.

 4) Fix crash when using MSG_PEEK with sockmap, from Anny Hu.

 5) The ucc_geth driver needs __netdev_watchdog_up exported, from
    Valentin Longchamp.

 6) Fix hashtable memory leak in dccp, from Wang Hai.

 7) Fix how nexthops are marked as FDB nexthops, from David Ahern.

 8) Fix mptcp races between shutdown and recvmsg, from Paolo Abeni.

 9) Fix crashes in tipc_disc_rcv(), from Tuong Lien.

10) Fix link speed reporting in iavf driver, from Brett Creeley.

11) When a channel is used for XSK and then reused again later for XSK,
    we forget to clear out the relevant data structures in mlx5 which
    causes all kinds of problems. Fix from Maxim Mikityanskiy.

12) Fix memory leak in genetlink, from Cong Wang.

13) Disallow sockmap attachments to UDP sockets, it simply won't work.
    From Lorenz Bauer.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (83 commits)
  net: ethernet: ti: ale: fix allmulti for nu type ale
  net: ethernet: ti: am65-cpsw-nuss: fix ale parameters init
  net: atm: Remove the error message according to the atomic context
  bpf: Undo internal BPF_PROBE_MEM in BPF insns dump
  libbpf: Support pre-initializing .bss global variables
  tools/bpftool: Fix skeleton codegen
  bpf: Fix memlock accounting for sock_hash
  bpf: sockmap: Don't attach programs to UDP sockets
  bpf: tcp: Recv() should return 0 when the peer socket is closed
  ibmvnic: Flush existing work items before device removal
  genetlink: clean up family attributes allocations
  net: ipa: header pad field only valid for AP->modem endpoint
  net: ipa: program upper nibbles of sequencer type
  net: ipa: fix modem LAN RX endpoint id
  net: ipa: program metadata mask differently
  ionic: add pcie_print_link_status
  rxrpc: Fix race between incoming ACK parser and retransmitter
  net/mlx5: E-Switch, Fix some error pointer dereferences
  net/mlx5: Don't fail driver on failure to create debugfs
  net/mlx5e: CT: Fix ipv6 nat header rewrite actions
  ...
2020-06-13 16:27:13 -07:00
Masahiro Yamada
a7f7f6248d treewide: replace '---help---' in Kconfig files with 'help'
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-14 01:57:21 +09:00
Cong Wang
b65ce380b7 genetlink: clean up family attributes allocations
genl_family_rcv_msg_attrs_parse() and genl_family_rcv_msg_attrs_free()
take a boolean parameter to determine whether allocate/free the family
attrs. This is unnecessary as we can just check family->parallel_ops.
More importantly, callers would not need to worry about pairing these
parameters correctly after this patch.

And this fixes a memory leak, as after commit c36f055591
("genetlink: fix memory leaks in genl_family_rcv_msg_dumpit()")
we call genl_family_rcv_msg_attrs_parse() for both parallel and
non-parallel cases.

Fixes: c36f055591 ("genetlink: fix memory leaks in genl_family_rcv_msg_dumpit()")
Reported-by: Ido Schimmel <idosch@idosch.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Tested-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-12 14:05:08 -07:00
Cong Wang
c36f055591 genetlink: fix memory leaks in genl_family_rcv_msg_dumpit()
There are two kinds of memory leaks in genl_family_rcv_msg_dumpit():

1. Before we call ops->start(), whenever an error happens, we forget
   to free the memory allocated in genl_family_rcv_msg_dumpit().

2. When ops->start() fails, the 'info' has been already installed on
   the per socket control block, so we should not free it here. More
   importantly, nlk->cb_running is still false at this point, so
   netlink_sock_destruct() cannot free it either.

The first kind of memory leaks is easier to resolve, but the second
one requires some deeper thoughts.

After reviewing how netfilter handles this, the most elegant solution
I find is just to use a similar way to allocate the memory, that is,
moving memory allocations from caller into ops->start(). With this,
we can solve both kinds of memory leaks: for 1), no memory allocation
happens before ops->start(); for 2), ops->start() handles its own
failures and 'info' is installed to the socket control block only
when success. The only ugliness here is we have to pass all local
variables on stack via a struct, but this is not hard to understand.

Alternatively, we can introduce a ops->free() to solve this too,
but it is overkill as only genetlink has this problem so far.

Fixes: 1927f41a22 ("net: genetlink: introduce dump info struct to be available during dumpit op")
Reported-by: syzbot+21f04f481f449c8db840@syzkaller.appspotmail.com
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Cc: Shaochun Chen <cscnull@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-04 15:33:45 -07:00
Yonghong Song
3c32cc1bce bpf: Enable bpf_iter targets registering ctx argument types
Commit b121b341e5 ("bpf: Add PTR_TO_BTF_ID_OR_NULL
support") adds a field btf_id_or_null_non0_off to
bpf_prog->aux structure to indicate that the
first ctx argument is PTR_TO_BTF_ID reg_type and
all others are PTR_TO_BTF_ID_OR_NULL.
This approach does not really scale if we have
other different reg types in the future, e.g.,
a pointer to a buffer.

This patch enables bpf_iter targets registering ctx argument
reg types which may be different from the default one.
For example, for pointers to structures, the default reg_type
is PTR_TO_BTF_ID for tracing program. The target can register
a particular pointer type as PTR_TO_BTF_ID_OR_NULL which can
be used by the verifier to enforce accesses.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200513180221.2949882-1-yhs@fb.com
2020-05-13 12:30:50 -07:00
Yonghong Song
15172a46fa bpf: net: Refactor bpf_iter target registration
Currently bpf_iter_reg_target takes parameters from target
and allocates memory to save them. This is really not
necessary, esp. in the future we may grow information
passed from targets to bpf_iter manager.

The patch refactors the code so target reg_info
becomes static and bpf_iter manager can just take
a reference to it.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200513180219.2949605-1-yhs@fb.com
2020-05-13 12:30:50 -07:00