Commit Graph

497 Commits

Author SHA1 Message Date
22fa15e6f5 rtnetlink: ndo_dflt_fdb_dump() only work for ARPHRD_ETHER devices
[ Upstream commit 688838934c ]

kmsan was able to trigger a kernel-infoleak using a gre device [1]

nlmsg_populate_fdb_fill() has a hard coded assumption
that dev->addr_len is ETH_ALEN, as normally guaranteed
for ARPHRD_ETHER devices.

A similar issue was fixed recently in commit da71577545
("rtnetlink: Disallow FDB configuration for non-Ethernet device")

[1]
BUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:143 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x4c0/0x2700 lib/iov_iter.c:576
CPU: 0 PID: 6697 Comm: syz-executor310 Not tainted 4.20.0-rc3+ #95
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x32d/0x480 lib/dump_stack.c:113
 kmsan_report+0x12c/0x290 mm/kmsan/kmsan.c:683
 kmsan_internal_check_memory+0x32a/0xa50 mm/kmsan/kmsan.c:743
 kmsan_copy_to_user+0x78/0xd0 mm/kmsan/kmsan_hooks.c:634
 copyout lib/iov_iter.c:143 [inline]
 _copy_to_iter+0x4c0/0x2700 lib/iov_iter.c:576
 copy_to_iter include/linux/uio.h:143 [inline]
 skb_copy_datagram_iter+0x4e2/0x1070 net/core/datagram.c:431
 skb_copy_datagram_msg include/linux/skbuff.h:3316 [inline]
 netlink_recvmsg+0x6f9/0x19d0 net/netlink/af_netlink.c:1975
 sock_recvmsg_nosec net/socket.c:794 [inline]
 sock_recvmsg+0x1d1/0x230 net/socket.c:801
 ___sys_recvmsg+0x444/0xae0 net/socket.c:2278
 __sys_recvmsg net/socket.c:2327 [inline]
 __do_sys_recvmsg net/socket.c:2337 [inline]
 __se_sys_recvmsg+0x2fa/0x450 net/socket.c:2334
 __x64_sys_recvmsg+0x4a/0x70 net/socket.c:2334
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x441119
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fffc7f008a8 EFLAGS: 00000207 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000441119
RDX: 0000000000000040 RSI: 00000000200005c0 RDI: 0000000000000003
RBP: 00000000006cc018 R08: 0000000000000100 R09: 0000000000000100
R10: 0000000000000100 R11: 0000000000000207 R12: 0000000000402080
R13: 0000000000402110 R14: 0000000000000000 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:246 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:261 [inline]
 kmsan_internal_chain_origin+0x13d/0x240 mm/kmsan/kmsan.c:469
 kmsan_memcpy_memmove_metadata+0x1a9/0xf70 mm/kmsan/kmsan.c:344
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:362
 __msan_memcpy+0x61/0x70 mm/kmsan/kmsan_instr.c:162
 __nla_put lib/nlattr.c:744 [inline]
 nla_put+0x20a/0x2d0 lib/nlattr.c:802
 nlmsg_populate_fdb_fill+0x444/0x810 net/core/rtnetlink.c:3466
 nlmsg_populate_fdb net/core/rtnetlink.c:3775 [inline]
 ndo_dflt_fdb_dump+0x73a/0x960 net/core/rtnetlink.c:3807
 rtnl_fdb_dump+0x1318/0x1cb0 net/core/rtnetlink.c:3979
 netlink_dump+0xc79/0x1c90 net/netlink/af_netlink.c:2244
 __netlink_dump_start+0x10c4/0x11d0 net/netlink/af_netlink.c:2352
 netlink_dump_start include/linux/netlink.h:216 [inline]
 rtnetlink_rcv_msg+0x141b/0x1540 net/core/rtnetlink.c:4910
 netlink_rcv_skb+0x394/0x640 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4965
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x1699/0x1740 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x13c7/0x1440 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 ___sys_sendmsg+0xe3b/0x1240 net/socket.c:2116
 __sys_sendmsg net/socket.c:2154 [inline]
 __do_sys_sendmsg net/socket.c:2163 [inline]
 __se_sys_sendmsg+0x305/0x460 net/socket.c:2161
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:246 [inline]
 kmsan_internal_poison_shadow+0x6d/0x130 mm/kmsan/kmsan.c:170
 kmsan_kmalloc+0xa1/0x100 mm/kmsan/kmsan_hooks.c:186
 __kmalloc+0x14c/0x4d0 mm/slub.c:3825
 kmalloc include/linux/slab.h:551 [inline]
 __hw_addr_create_ex net/core/dev_addr_lists.c:34 [inline]
 __hw_addr_add_ex net/core/dev_addr_lists.c:80 [inline]
 __dev_mc_add+0x357/0x8a0 net/core/dev_addr_lists.c:670
 dev_mc_add+0x6d/0x80 net/core/dev_addr_lists.c:687
 ip_mc_filter_add net/ipv4/igmp.c:1128 [inline]
 igmp_group_added+0x4d4/0xb80 net/ipv4/igmp.c:1311
 __ip_mc_inc_group+0xea9/0xf70 net/ipv4/igmp.c:1444
 ip_mc_inc_group net/ipv4/igmp.c:1453 [inline]
 ip_mc_up+0x1c3/0x400 net/ipv4/igmp.c:1775
 inetdev_event+0x1d03/0x1d80 net/ipv4/devinet.c:1522
 notifier_call_chain kernel/notifier.c:93 [inline]
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x13d/0x240 kernel/notifier.c:401
 __dev_notify_flags+0x3da/0x860 net/core/dev.c:1733
 dev_change_flags+0x1ac/0x230 net/core/dev.c:7569
 do_setlink+0x165f/0x5ea0 net/core/rtnetlink.c:2492
 rtnl_newlink+0x2ad7/0x35a0 net/core/rtnetlink.c:3111
 rtnetlink_rcv_msg+0x1148/0x1540 net/core/rtnetlink.c:4947
 netlink_rcv_skb+0x394/0x640 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4965
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x1699/0x1740 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x13c7/0x1440 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 ___sys_sendmsg+0xe3b/0x1240 net/socket.c:2116
 __sys_sendmsg net/socket.c:2154 [inline]
 __do_sys_sendmsg net/socket.c:2163 [inline]
 __se_sys_sendmsg+0x305/0x460 net/socket.c:2161
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Bytes 36-37 of 105 are uninitialized
Memory access of size 105 starts at ffff88819686c000
Data copied to user address 0000000020000380

Fixes: d83b060360 ("net: add fdb generic dump routine")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Ido Schimmel <idosch@mellanox.com>
Cc: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-17 09:28:47 +01:00
4ca72d6336 rtnetlink: Disallow FDB configuration for non-Ethernet device
[ Upstream commit da71577545 ]

When an FDB entry is configured, the address is validated to have the
length of an Ethernet address, but the device for which the address is
configured can be of any type.

The above can result in the use of uninitialized memory when the address
is later compared against existing addresses since 'dev->addr_len' is
used and it may be greater than ETH_ALEN, as with ip6tnl devices.

Fix this by making sure that FDB entries are only configured for
Ethernet devices.

BUG: KMSAN: uninit-value in memcmp+0x11d/0x180 lib/string.c:863
CPU: 1 PID: 4318 Comm: syz-executor998 Not tainted 4.19.0-rc3+ #49
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0x14b/0x190 lib/dump_stack.c:113
  kmsan_report+0x183/0x2b0 mm/kmsan/kmsan.c:956
  __msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:645
  memcmp+0x11d/0x180 lib/string.c:863
  dev_uc_add_excl+0x165/0x7b0 net/core/dev_addr_lists.c:464
  ndo_dflt_fdb_add net/core/rtnetlink.c:3463 [inline]
  rtnl_fdb_add+0x1081/0x1270 net/core/rtnetlink.c:3558
  rtnetlink_rcv_msg+0xa0b/0x1530 net/core/rtnetlink.c:4715
  netlink_rcv_skb+0x36e/0x5f0 net/netlink/af_netlink.c:2454
  rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4733
  netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
  netlink_unicast+0x1638/0x1720 net/netlink/af_netlink.c:1343
  netlink_sendmsg+0x1205/0x1290 net/netlink/af_netlink.c:1908
  sock_sendmsg_nosec net/socket.c:621 [inline]
  sock_sendmsg net/socket.c:631 [inline]
  ___sys_sendmsg+0xe70/0x1290 net/socket.c:2114
  __sys_sendmsg net/socket.c:2152 [inline]
  __do_sys_sendmsg net/socket.c:2161 [inline]
  __se_sys_sendmsg+0x2a3/0x3d0 net/socket.c:2159
  __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2159
  do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
  entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x440ee9
Code: e8 cc ab 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 bb 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff6a93b518 EFLAGS: 00000213 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440ee9
RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000213 R12: 000000000000b4b0
R13: 0000000000401ec0 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
  kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
  kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:181
  kmsan_kmalloc+0x98/0x100 mm/kmsan/kmsan_hooks.c:91
  kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:100
  slab_post_alloc_hook mm/slab.h:446 [inline]
  slab_alloc_node mm/slub.c:2718 [inline]
  __kmalloc_node_track_caller+0x9e7/0x1160 mm/slub.c:4351
  __kmalloc_reserve net/core/skbuff.c:138 [inline]
  __alloc_skb+0x2f5/0x9e0 net/core/skbuff.c:206
  alloc_skb include/linux/skbuff.h:996 [inline]
  netlink_alloc_large_skb net/netlink/af_netlink.c:1189 [inline]
  netlink_sendmsg+0xb49/0x1290 net/netlink/af_netlink.c:1883
  sock_sendmsg_nosec net/socket.c:621 [inline]
  sock_sendmsg net/socket.c:631 [inline]
  ___sys_sendmsg+0xe70/0x1290 net/socket.c:2114
  __sys_sendmsg net/socket.c:2152 [inline]
  __do_sys_sendmsg net/socket.c:2161 [inline]
  __se_sys_sendmsg+0x2a3/0x3d0 net/socket.c:2159
  __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2159
  do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
  entry_SYSCALL_64_after_hwframe+0x63/0xe7

v2:
* Make error message more specific (David)

Fixes: 090096bf3d ("net: generic fdb support for drivers without ndo_fdb_<op>")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-and-tested-by: syzbot+3a288d5f5530b901310e@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+d53ab4e92a1db04110ff@syzkaller.appspotmail.com
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-04 14:52:50 +01:00
a8b0f004eb rtnl: limit IFLA_NUM_TX_QUEUES and IFLA_NUM_RX_QUEUES to 4096
[ Upstream commit 0e1d6eca51 ]

We have an impressive number of syzkaller bugs that are linked
to the fact that syzbot was able to create a networking device
with millions of TX (or RX) queues.

Let's limit the number of RX/TX queues to 4096, this really should
cover all known cases.

A separate patch will add various cond_resched() in the loops
handling sysfs entries at device creation and dismantle.

Tested:

lpaa6:~# ip link add gre-4097 numtxqueues 4097 numrxqueues 4097 type ip6gretap
RTNETLINK answers: Invalid argument

lpaa6:~# time ip link add gre-4096 numtxqueues 4096 numrxqueues 4096 type ip6gretap

real	0m0.180s
user	0m0.000s
sys	0m0.107s

Fixes: 76ff5cc919 ("rtnl: allow to specify number of rx and tx queues on device creation")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:19 +02:00
5f999abba3 rtnetlink: fix rtnl_fdb_dump() for ndmsg header
[ Upstream commit bd961c9bc6 ]

Currently, rtnl_fdb_dump() assumes the family header is 'struct ifinfomsg',
which is not always true -- 'struct ndmsg' is used by iproute2 ('ip neigh').

The problem is, the function bails out early if nlmsg_parse() fails, which
does occur for iproute2 usage of 'struct ndmsg' because the payload length
is shorter than the family header alone (as 'struct ifinfomsg' is assumed).

This breaks backward compatibility with userspace -- nothing is sent back.

Some examples with iproute2 and netlink library for go [1]:

 1) $ bridge fdb show
    33:33:00:00:00:01 dev ens3 self permanent
    01:00:5e:00:00:01 dev ens3 self permanent
    33:33:ff:15:98:30 dev ens3 self permanent

      This one works, as it uses 'struct ifinfomsg'.

      fdb_show() @ iproute2/bridge/fdb.c
        """
        .n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
        ...
        if (rtnl_dump_request(&rth, RTM_GETNEIGH, [...]
        """

 2) $ ip --family bridge neigh
    RTNETLINK answers: Invalid argument
    Dump terminated

      This one fails, as it uses 'struct ndmsg'.

      do_show_or_flush() @ iproute2/ip/ipneigh.c
        """
        .n.nlmsg_type = RTM_GETNEIGH,
        .n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)),
        """

 3) $ ./neighlist
    < no output >

      This one fails, as it uses 'struct ndmsg'-based.

      neighList() @ netlink/neigh_linux.go
        """
        req := h.newNetlinkRequest(unix.RTM_GETNEIGH, [...]
        msg := Ndmsg{
        """

The actual breakage was introduced by commit 0ff50e83b5 ("net: rtnetlink:
bail out from rtnl_fdb_dump() on parse error"), because nlmsg_parse() fails
if the payload length (with the _actual_ family header) is less than the
family header length alone (which is assumed, in parameter 'hdrlen').
This is true in the examples above with struct ndmsg, with size and payload
length shorter than struct ifinfomsg.

However, that commit just intends to fix something under the assumption the
family header is indeed an 'struct ifinfomsg' - by preventing access to the
payload as such (via 'ifm' pointer) if the payload length is not sufficient
to actually contain it.

The assumption was introduced by commit 5e6d243587 ("bridge: netlink dump
interface at par with brctl"), to support iproute2's 'bridge fdb' command
(not 'ip neigh') which indeed uses 'struct ifinfomsg', thus is not broken.

So, in order to unbreak the 'struct ndmsg' family headers and still allow
'struct ifinfomsg' to continue to work, check for the known message sizes
used with 'struct ndmsg' in iproute2 (with zero or one attribute which is
not used in this function anyway) then do not parse the data as ifinfomsg.

Same examples with this patch applied (or revert/before the original fix):

    $ bridge fdb show
    33:33:00:00:00:01 dev ens3 self permanent
    01:00:5e:00:00:01 dev ens3 self permanent
    33:33:ff:15:98:30 dev ens3 self permanent

    $ ip --family bridge neigh
    dev ens3 lladdr 33:33:00:00:00:01 PERMANENT
    dev ens3 lladdr 01:00:5e:00:00:01 PERMANENT
    dev ens3 lladdr 33:33:ff:15:98:30 PERMANENT

    $ ./neighlist
    netlink.Neigh{LinkIndex:2, Family:7, State:128, Type:0, Flags:2, IP:net.IP(nil), HardwareAddr:net.HardwareAddr{0x33, 0x33, 0x0, 0x0, 0x0, 0x1}, LLIPAddr:net.IP(nil), Vlan:0, VNI:0}
    netlink.Neigh{LinkIndex:2, Family:7, State:128, Type:0, Flags:2, IP:net.IP(nil), HardwareAddr:net.HardwareAddr{0x1, 0x0, 0x5e, 0x0, 0x0, 0x1}, LLIPAddr:net.IP(nil), Vlan:0, VNI:0}
    netlink.Neigh{LinkIndex:2, Family:7, State:128, Type:0, Flags:2, IP:net.IP(nil), HardwareAddr:net.HardwareAddr{0x33, 0x33, 0xff, 0x15, 0x98, 0x30}, LLIPAddr:net.IP(nil), Vlan:0, VNI:0}

Tested on mainline (v4.19-rc6) and net-next (3bd09b05b0).

References:

[1] netlink library for go (test-case)
    https://github.com/vishvananda/netlink

    $ cat ~/go/src/neighlist/main.go
    package main
    import ("fmt"; "syscall"; "github.com/vishvananda/netlink")
    func main() {
        neighs, _ := netlink.NeighList(0, syscall.AF_BRIDGE)
        for _, neigh := range neighs { fmt.Printf("%#v\n", neigh) }
    }

    $ export GOPATH=~/go
    $ go get github.com/vishvananda/netlink
    $ go build neighlist
    $ ~/go/src/neighlist/neighlist

Thanks to David Ahern for suggestions to improve this patch.

Fixes: 0ff50e83b5 ("net: rtnetlink: bail out from rtnl_fdb_dump() on parse error")
Fixes: 5e6d243587 ("bridge: netlink dump interface at par with brctl")
Reported-by: Aidan Obley <aobley@pivotal.io>
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:18 +02:00
23557c5d34 rtnetlink: add rtnl_link_state check in rtnl_configure_link
[ Upstream commit 5025f7f7d5 ]

rtnl_configure_link sets dev->rtnl_link_state to
RTNL_LINK_INITIALIZED and unconditionally calls
__dev_notify_flags to notify user-space of dev flags.

current call sequence for rtnl_configure_link
rtnetlink_newlink
    rtnl_link_ops->newlink
    rtnl_configure_link (unconditionally notifies userspace of
                         default and new dev flags)

If a newlink handler wants to call rtnl_configure_link
early, we will end up with duplicate notifications to
user-space.

This patch fixes rtnl_configure_link to check rtnl_link_state
and call __dev_notify_flags with gchanges = 0 if already
RTNL_LINK_INITIALIZED.

Later in the series, this patch will help the following sequence
where a driver implementing newlink can call rtnl_configure_link
to initialize the link early.

makes the following call sequence work:
rtnetlink_newlink
    rtnl_link_ops->newlink (vxlan) -> rtnl_configure_link (initializes
                                                link and notifies
                                                user-space of default
                                                dev flags)
    rtnl_configure_link (updates dev flags if requested by user ifm
                         and notifies user-space of new dev flags)

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-28 07:55:42 +02:00
c931c9aee2 rtnetlink: validate attributes in do_setlink()
[ Upstream commit 644c7eebbf ]

It seems that rtnl_group_changelink() can call do_setlink
while a prior call to validate_linkmsg(dev = NULL, ...) could
not validate IFLA_ADDRESS / IFLA_BROADCAST

Make sure do_setlink() calls validate_linkmsg() instead
of letting its callers having this responsibility.

With help from Dmitry Vyukov, thanks a lot !

BUG: KMSAN: uninit-value in is_valid_ether_addr include/linux/etherdevice.h:199 [inline]
BUG: KMSAN: uninit-value in eth_prepare_mac_addr_change net/ethernet/eth.c:275 [inline]
BUG: KMSAN: uninit-value in eth_mac_addr+0x203/0x2b0 net/ethernet/eth.c:308
CPU: 1 PID: 8695 Comm: syz-executor3 Not tainted 4.17.0-rc5+ #103
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x149/0x260 mm/kmsan/kmsan.c:1084
 __msan_warning_32+0x6e/0xc0 mm/kmsan/kmsan_instr.c:686
 is_valid_ether_addr include/linux/etherdevice.h:199 [inline]
 eth_prepare_mac_addr_change net/ethernet/eth.c:275 [inline]
 eth_mac_addr+0x203/0x2b0 net/ethernet/eth.c:308
 dev_set_mac_address+0x261/0x530 net/core/dev.c:7157
 do_setlink+0xbc3/0x5fc0 net/core/rtnetlink.c:2317
 rtnl_group_changelink net/core/rtnetlink.c:2824 [inline]
 rtnl_newlink+0x1fe9/0x37a0 net/core/rtnetlink.c:2976
 rtnetlink_rcv_msg+0xa32/0x1560 net/core/rtnetlink.c:4646
 netlink_rcv_skb+0x378/0x600 net/netlink/af_netlink.c:2448
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4664
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x1678/0x1750 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x104f/0x1350 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg net/socket.c:639 [inline]
 ___sys_sendmsg+0xec0/0x1310 net/socket.c:2117
 __sys_sendmsg net/socket.c:2155 [inline]
 __do_sys_sendmsg net/socket.c:2164 [inline]
 __se_sys_sendmsg net/socket.c:2162 [inline]
 __x64_sys_sendmsg+0x331/0x460 net/socket.c:2162
 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x455a09
RSP: 002b:00007fc07480ec68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fc07480f6d4 RCX: 0000000000455a09
RDX: 0000000000000000 RSI: 00000000200003c0 RDI: 0000000000000014
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000005d0 R14: 00000000006fdc20 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:294 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:685
 kmsan_memcpy_origins+0x11d/0x170 mm/kmsan/kmsan.c:527
 __msan_memcpy+0x109/0x160 mm/kmsan/kmsan_instr.c:478
 do_setlink+0xb84/0x5fc0 net/core/rtnetlink.c:2315
 rtnl_group_changelink net/core/rtnetlink.c:2824 [inline]
 rtnl_newlink+0x1fe9/0x37a0 net/core/rtnetlink.c:2976
 rtnetlink_rcv_msg+0xa32/0x1560 net/core/rtnetlink.c:4646
 netlink_rcv_skb+0x378/0x600 net/netlink/af_netlink.c:2448
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4664
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x1678/0x1750 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x104f/0x1350 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg net/socket.c:639 [inline]
 ___sys_sendmsg+0xec0/0x1310 net/socket.c:2117
 __sys_sendmsg net/socket.c:2155 [inline]
 __do_sys_sendmsg net/socket.c:2164 [inline]
 __se_sys_sendmsg net/socket.c:2162 [inline]
 __x64_sys_sendmsg+0x331/0x460 net/socket.c:2162
 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:189
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:315
 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan.c:322
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2753 [inline]
 __kmalloc_node_track_caller+0xb32/0x11b0 mm/slub.c:4395
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cb/0x9e0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:988 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline]
 netlink_sendmsg+0x76e/0x1350 net/netlink/af_netlink.c:1876
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg net/socket.c:639 [inline]
 ___sys_sendmsg+0xec0/0x1310 net/socket.c:2117
 __sys_sendmsg net/socket.c:2155 [inline]
 __do_sys_sendmsg net/socket.c:2164 [inline]
 __se_sys_sendmsg net/socket.c:2162 [inline]
 __x64_sys_sendmsg+0x331/0x460 net/socket.c:2162
 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: e7ed828f10 ("netlink: support setting devgroup parameters")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-11 22:49:22 +02:00
2459b4c635 net: enable interface alias removal via rtnl
IFLA_IFALIAS is defined as NLA_STRING. It means that the minimal length of
the attribute is 1 ("\0"). However, to remove an alias, the attribute
length must be 0 (see dev_set_alias()).

Let's define the type to NLA_BINARY to allow 0-length string, so that the
alias can be removed.

Example:
$ ip l s dummy0 alias foo
$ ip l l dev dummy0
5: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether ae:20:30:4f:a7:f3 brd ff:ff:ff:ff:ff:ff
    alias foo

Before the patch:
$ ip l s dummy0 alias ""
RTNETLINK answers: Numerical result out of range

After the patch:
$ ip l s dummy0 alias ""
$ ip l l dev dummy0
5: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether ae:20:30:4f:a7:f3 brd ff:ff:ff:ff:ff:ff

CC: Oliver Hartkopp <oliver@hartkopp.net>
CC: Stephen Hemminger <stephen@networkplumber.org>
Fixes: 96ca4a2cc1 ("net: remove ifalias on empty given alias")
Reported-by: Julien FLoret <julien.floret@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-16 20:52:43 +01:00
2d7f669b42 rtnetlink: do not set notification for tx_queue_len in do_setlink
NETDEV_CHANGE_TX_QUEUE_LEN event process in rtnetlink_event would
send a notification for userspace and tx_queue_len's setting in
do_setlink would trigger NETDEV_CHANGE_TX_QUEUE_LEN.

So it shouldn't set DO_SETLINK_NOTIFY status for this change to
send a notification any more.

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>
2017-10-16 20:48:45 +01:00
64ff90cc2e rtnetlink: check DO_SETLINK_NOTIFY correctly in do_setlink
The check 'status & DO_SETLINK_NOTIFY' in do_setlink doesn't really
work after status & DO_SETLINK_MODIFIED, as:

  DO_SETLINK_MODIFIED 0x1
  DO_SETLINK_NOTIFY 0x3

Considering that notifications are suppposed to be sent only when
status have the flag DO_SETLINK_NOTIFY, the right check would be:

  (status & DO_SETLINK_NOTIFY) == DO_SETLINK_NOTIFY

This would avoid lots of duplicated notifications when setting some
properties of a link.

Fixes: ba9989069f ("rtnl/do_setlink(): notify when a netdev is modified")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: David Ahern <dsahern@gmail.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-16 20:48:45 +01:00
dc709f3757 rtnetlink: bring NETDEV_CHANGEUPPER event process back in rtnetlink_event
libteam needs this event notification in userspace when dev's master
dev has been changed. After this, the redundant notifications issue
would be fixed in the later patch 'rtnetlink: check DO_SETLINK_NOTIFY
correctly in do_setlink'.

Fixes: b6b36eb23a ("rtnetlink: Do not generate notifications for NETDEV_CHANGEUPPER event")
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>
2017-10-16 20:48:45 +01:00
e6e6659446 rtnetlink: bring NETDEV_POST_TYPE_CHANGE event process back in rtnetlink_event
As I said in patch 'rtnetlink: bring NETDEV_CHANGEMTU event process back
in rtnetlink_event', removing NETDEV_POST_TYPE_CHANGE event was not the
right fix for the redundant notifications issue.

So bring this event process back to rtnetlink_event and the old redundant
notifications issue would be fixed in the later patch 'rtnetlink: check
DO_SETLINK_NOTIFY correctly in do_setlink'.

Fixes: aef091ae58 ("rtnetlink: Do not generate notifications for POST_TYPE_CHANGE event")
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>
2017-10-16 20:48:45 +01:00
ebdcf0450b rtnetlink: bring NETDEV_CHANGE_TX_QUEUE_LEN event process back in rtnetlink_event
The same fix for changing mtu in the patch 'rtnetlink: bring
NETDEV_CHANGEMTU event process back in rtnetlink_event' is
needed for changing tx_queue_len.

Note that the redundant notifications issue for tx_queue_len
will be fixed in the later patch 'rtnetlink: do not send
notification for tx_queue_len in do_setlink'.

Fixes: 27b3b551d8 ("rtnetlink: Do not generate notifications for NETDEV_CHANGE_TX_QUEUE_LEN event")
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>
2017-10-16 20:48:44 +01:00
8a212589fe rtnetlink: bring NETDEV_CHANGEMTU event process back in rtnetlink_event
Commit 085e1a65f0 ("rtnetlink: Do not generate notifications for MTU
events") tried to fix the redundant notifications issue when ip link
set mtu by removing NETDEV_CHANGEMTU event process in rtnetlink_event.

But it also resulted in no notification generated when dev's mtu is
changed via other methods, like:
  'ifconfig eth1 mtu 1400' or 'echo 1400 > /sys/class/net/eth1/mtu'
It would cause users not to be notified by this change.

This patch is to fix it by bringing NETDEV_CHANGEMTU event back into
rtnetlink_event, and the redundant notifications issue will be fixed
in the later patch 'rtnetlink: check DO_SETLINK_NOTIFY correctly in
do_setlink'.

Fixes: 085e1a65f0 ("rtnetlink: Do not generate notifications for MTU events")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-16 20:48:44 +01:00
ce024f42c2 net: rtnetlink: fix info leak in RTM_GETSTATS call
When RTM_GETSTATS was added the fields of its header struct were not all
initialized when returning the result thus leaking 4 bytes of information
to user-space per rtnl_fill_statsinfo call, so initialize them now. Thanks
to Alexander Potapenko for the detailed report and bisection.

Reported-by: Alexander Potapenko <glider@google.com>
Fixes: 10c9ead9f3 ("rtnetlink: add new RTM_GETSTATS message to dump link stats")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-03 10:18:00 -07:00
d0225784be rtnelink: Move link dump consistency check out of the loop
Calls to rtnl_dump_ifinfo() are protected by RTNL lock. So are the
{list,unlist}_netdevice() calls where we bump the net->dev_base_seq
number.

For this reason net->dev_base_seq can't change under out feet while
we're looping over links in rtnl_dump_ifinfo(). So move the check for
net->dev_base_seq change (since the last time we were called) out of the
loop.

This way we avoid giving a wrong impression that there are concurrent
updates to the link list going on while we're iterating over them.

Signed-off-by: Jakub Sitnicki <jkbs@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-13 19:43:57 -07:00
8caa38b56c rtnetlink: fallback to UNSPEC if current family has no doit callback
We need to use PF_UNSPEC in case the requested family has no doit
callback, otherwise this now fails with EOPNOTSUPP instead of running the
unspec doit callback, as before.

Fixes: 6853dd4881 ("rtnetlink: protect handler table with rcu")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-10 09:50:22 -07:00
d38a65125f rtnetlink: init handler refcounts to 1
If using CONFIG_REFCOUNT_FULL=y we get following splat:
 refcount_t: increment on 0; use-after-free.
WARNING: CPU: 0 PID: 304 at lib/refcount.c:152 refcount_inc+0x47/0x50
Call Trace:
 rtnetlink_rcv_msg+0x191/0x260
 ...

This warning is harmless (0 is "no callback running", not "memory
was freed").

Use '1' as the new 'no handler is running' base instead of 0 to avoid
this.

Fixes: 019a316992 ("rtnetlink: add reference counting to prevent module unload while dump is in progress")
Reported-by: Sabrina Dubroca <sdubroca@redhat.com>
Reported-by: kernel test robot <fengguang.wu@intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-10 09:50:22 -07:00
8515ae3843 rtnetlink: switch rtnl_link_get_slave_info_data_size to rcu
David Ahern reports following splat:
 RTNL: assertion failed at net/core/dev.c (5717)
 netdev_master_upper_dev_get+0x5f/0x70
 if_nlmsg_size+0x158/0x240
 rtnl_calcit.isra.26+0xa3/0xf0

rtnl_link_get_slave_info_data_size currently assumes RTNL protection, but
there appears to be no hard requirement for this, so use rcu instead.

At the time of this writing, there are three 'get_slave_size' callbacks
(now invoked under rcu): bond_get_slave_size, vrf_get_slave_size and
br_port_get_slave_size, all return constant only (i.e. they don't sleep).

Fixes: 6853dd4881 ("rtnetlink: protect handler table with rcu")
Reported-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-10 09:50:22 -07:00
5c2bb9b6e2 rtnetlink: do not use RTM_GETLINK directly
Userspace sends RTM_GETLINK type, but the kernel substracts
RTM_BASE from this, i.e. 'type' doesn't contain RTM_GETLINK
anymore but instead RTM_GETLINK - RTM_BASE.

This caused the calcit callback to not be invoked when it
should have been (and vice versa).

While at it, also fix a off-by one when checking family index. vs
handler array size.

Fixes: e1fa6d216d ("rtnetlink: call rtnl_calcit directly")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-10 09:50:22 -07:00
377cb24884 rtnetlink: use rcu_dereference_raw to silence rcu splat
Ido reports a rcu splat in __rtnl_register.
The splat is correct; as rtnl_register doesn't grab any logs
and doesn't use rcu locks either.  It has always been like this.
handler families are not registered in parallel so there are no
races wrt. the kmalloc ordering.

The only reason to use rcu_dereference in the first place was to
avoid sparse from complaining about this.

Thus this switches to _raw() to not have rcu checks here.

The alternative is to add rtnl locking to register/unregister,
however, I don't see a compelling reason to do so as this has been
lockless for the past twenty years or so.

Fixes: 6853dd4881 ("rtnetlink: protect handler table with rcu")
Reported-by: Ido Schimmel <idosch@idosch.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Tested-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-10 09:50:21 -07:00
62256f98f2 rtnetlink: add RTNL_FLAG_DOIT_UNLOCKED
Allow callers to tell rtnetlink core that its doit callback
should be invoked without holding rtnl mutex.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 16:57:38 -07:00
6853dd4881 rtnetlink: protect handler table with rcu
Note that netlink dumps still acquire rtnl mutex via the netlink
dump infrastructure.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 16:57:38 -07:00
0cc09020ae rtnetlink: small rtnl lock pushdown
instead of rtnl lock/unload at the top level, push it down
to the called function.

This is just an intermediate step, next commit switches protection
of the rtnl_link ops table to rcu, in which case (for dumps) the
rtnl lock is acquired only by the netlink dumper infrastructure
(current lock/unlock/dump/lock/unlock rtnl sequence becomes
 rcu lock/rcu unlock/dump).

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 16:57:38 -07:00
019a316992 rtnetlink: add reference counting to prevent module unload while dump is in progress
I don't see what prevents rmmod (unregister_all is called) while a dump
is active.

Even if we'd add rtnl lock/unlock pair to unregister_all (as done here),
thats not enough either as rtnl_lock is released right before the dump
process starts.

So this adds a refcount:
 * acquire rtnl mutex
 * bump refcount
 * release mutex
 * start the dump

... and make unregister_all remove the callbacks (no new dumps possible)
and then wait until refcount is 0.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 16:57:38 -07:00
b97bac64a5 rtnetlink: make rtnl_register accept a flags parameter
This change allows us to later indicate to rtnetlink core that certain
doit functions should be called without acquiring rtnl_mutex.

This change should have no effect, we simply replace the last (now
unused) calcit argument with the new flag.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 16:57:38 -07:00
e1fa6d216d rtnetlink: call rtnl_calcit directly
There is only a single place in the kernel that regisers the "calcit"
callback (to determine min allocation for dumps).

This is in rtnetlink.c for PF_UNSPEC RTM_GETLINK.
The function that checks for calcit presence at run time will first check
the requested family (which will always fail for !PF_UNSPEC as no callsite
registers this), then falls back to checking PF_UNSPEC.

Therefore we can just check if type is RTM_GETLINK and then do a direct
call.  Because of fallback to PF_UNSPEC all RTM_GETLINK types used this
regardless of family.

This has the advantage that we don't need to allocate space for
the function pointer for all the other families.

A followup patch will drop the calcit function pointer from the
rtnl_link callback structure.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 16:57:38 -07:00
153711f942 rtnetlink: allocate more memory for dev_set_mac_address()
virtnet_set_mac_address() interprets mac address as struct
sockaddr, but upper layer only allocates dev->addr_len
which is ETH_ALEN + sizeof(sa_family_t) in this case.

We lack a unified definition for mac address, so just fix
the upper layer, this also allows drivers to interpret it
to struct sockaddr freely.

Reported-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-20 15:23:22 -07:00
3753654e54 Revert "rtnetlink: Do not generate notifications for CHANGEADDR event"
This reverts commit cd8966e75e.

The duplicate CHANGEADDR event message is sent regardless of link
status whereas the setlink changes only generate a notification when
the link is up. Not sending a notification when the link is down breaks
dhcpcd which only processes hwaddr changes when the link is down.

Fixes reported regression:
    https://bugzilla.kernel.org/show_bug.cgi?id=196355

Reported-by: Yaroslav Isakov <yaroslav.isakov@gmail.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-19 22:29:41 -07:00
633547973f net: convert sk_buff.users from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-01 07:39:07 -07:00
d116ffc770 net: add netlink_ext_ack argument to rtnl_link_ops.slave_validate
Add support for extended error reporting.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-26 23:13:22 -04:00
17dd0ec470 net: add netlink_ext_ack argument to rtnl_link_ops.slave_changelink
Add support for extended error reporting.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-26 23:13:22 -04:00
a8b8a889e3 net: add netlink_ext_ack argument to rtnl_link_ops.validate
Add support for extended error reporting.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-26 23:13:22 -04:00
ad744b223c net: add netlink_ext_ack argument to rtnl_link_ops.changelink
Add support for extended error reporting.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-26 23:13:22 -04:00
7a3f4a1851 net: add netlink_ext_ack argument to rtnl_link_ops.newlink
Add support for extended error reporting.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-26 23:13:21 -04:00
ce158e580a xdp: add reporting of offload mode
Extend the XDP_ATTACHED_* values to include offloaded mode.
Let drivers report whether program is installed in the driver
or the HW by changing the prog_attached field from bool to
u8 (type of the netlink attribute).

Exploit the fact that the value of XDP_ATTACHED_DRV is 1,
therefore since all drivers currently assign the mode with
double negation:
       mode = !!xdp_prog;
no drivers have to be modified.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-23 13:42:20 -04:00
ee5d032f7d xdp: add HW offload mode flag for installing programs
Add an installation-time flag for requesting that the program
be installed only if it can be offloaded to HW.

Internally new command for ndo_xdp is added, this way we avoid
putting checks into drivers since they all return -EINVAL on
an unknown command.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-23 13:42:19 -04:00
3d09198243 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two entries being added at the same time to the IFLA
policy table, whilst parallel bug fixes to decnet
routing dst handling overlapping with the dst gc removal
in net-next.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-21 17:35:22 -04:00
5f729eaabe rtnetlink: add restricted rtnl groups for ipv4 and ipv6 mroute
Add RTNLGRP_{IPV4,IPV6}_MROUTE_R as two new restricted groups for the
NETLINK_ROUTE family.
Binding to these groups specifically requires CAP_NET_ADMIN to allow
multicast of sensitive messages (e.g. mroute cache reports).

Suggested-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Julien Gomes <julien@arista.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-21 11:22:52 -04:00
db833d40ad rtnetlink: add IFLA_GROUP to ifla_policy
Network interface groups support added while ago, however
there is no IFLA_GROUP attribute description in policy
and netlink message size calculations until now.

Add IFLA_GROUP attribute to the policy.

Fixes: cbda10fa97 ("net_device: add support for network device groups")
Signed-off-by: Serhey Popovych <serhe.popovych@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-20 15:36:16 -04:00
58038695e6 net: Add IFLA_XDP_PROG_ID
Expose prog_id through IFLA_XDP_PROG_ID.  This patch
makes modification to generic_xdp.  The later patches will
modify other xdp-supported drivers.

prog_id is added to struct net_dev_xdp.

iproute2 patch will be followed. Here is how the 'ip link'
will look like:
> ip link show eth0
3: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 xdp(prog_id:1) qdisc fq_codel state UP mode DEFAULT group default qlen 1000

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-16 11:58:36 -04:00
0ddead90b2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The conflicts were two cases of overlapping changes in
batman-adv and the qed driver.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-15 11:59:32 -04:00
0eed9cf584 net: Zero ifla_vf_info in rtnl_fill_vfinfo()
Some of the structure's fields are not initialized by the
rtnetlink. If driver doesn't set those in ndo_get_vf_config(),
they'd leak memory to user.

Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
CC: Michal Schmidt <mschmidt@redhat.com>
Reviewed-by: Greg Rose <gvrose8192@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-08 10:58:02 -04:00
8c6c918da1 rtnetlink: use the new rtnl_get_event() interface
Small clean-up to rtmsg_ifinfo() to use the rtnl_get_event()
interface instead of using 'internal' values directly.

Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-31 13:08:36 -04:00
3d3ea5af5c rtnl: Add support for netdev event to link messages
When netdev events happen, a rtnetlink_event() handler will send
messages for every event in it's white list.  These messages contain
current information about a particular device, but they do not include
the iformation about which event just happened.  So, it is impossible
to tell what just happend for these events.

This patch adds a new extension to RTM_NEWLINK message called IFLA_EVENT
that would have an encoding of event that triggered this
message.  This would allow the the message consumer to easily determine
if it needs to perform certain actions.

Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-27 18:51:41 -04:00
34aa83c2fc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Overlapping changes in drivers/net/phy/marvell.c, bug fix in 'net'
restricting a HW workaround alongside cleanups in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-26 20:46:35 -04:00
0ff50e83b5 net: rtnetlink: bail out from rtnl_fdb_dump() on parse error
rtnl_fdb_dump() failed to check the result of nlmsg_parse(), which led
to contents of |ifm| being uninitialized because nlh->nlmsglen was too
small to accommodate |ifm|. The uninitialized data may affect some
branches and result in unwanted effects, although kernel data doesn't
seem to leak to the userspace directly.

The bug has been detected with KMSAN and syzkaller.

For the record, here is the KMSAN report:

==================================================================
BUG: KMSAN: use of unitialized memory in rtnl_fdb_dump+0x5dc/0x1000
CPU: 0 PID: 1039 Comm: probe Not tainted 4.11.0-rc5+ #2727
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16
 dump_stack+0x143/0x1b0 lib/dump_stack.c:52
 kmsan_report+0x12a/0x180 mm/kmsan/kmsan.c:1007
 __kmsan_warning_32+0x66/0xb0 mm/kmsan/kmsan_instr.c:491
 rtnl_fdb_dump+0x5dc/0x1000 net/core/rtnetlink.c:3230
 netlink_dump+0x84f/0x1190 net/netlink/af_netlink.c:2168
 __netlink_dump_start+0xc97/0xe50 net/netlink/af_netlink.c:2258
 netlink_dump_start ./include/linux/netlink.h:165
 rtnetlink_rcv_msg+0xae9/0xb40 net/core/rtnetlink.c:4094
 netlink_rcv_skb+0x339/0x5a0 net/netlink/af_netlink.c:2339
 rtnetlink_rcv+0x83/0xa0 net/core/rtnetlink.c:4110
 netlink_unicast_kernel net/netlink/af_netlink.c:1272
 netlink_unicast+0x13b7/0x1480 net/netlink/af_netlink.c:1298
 netlink_sendmsg+0x10b8/0x10f0 net/netlink/af_netlink.c:1844
 sock_sendmsg_nosec net/socket.c:633
 sock_sendmsg net/socket.c:643
 ___sys_sendmsg+0xd4b/0x10f0 net/socket.c:1997
 __sys_sendmsg net/socket.c:2031
 SYSC_sendmsg+0x2c6/0x3f0 net/socket.c:2042
 SyS_sendmsg+0x87/0xb0 net/socket.c:2038
 do_syscall_64+0x102/0x150 arch/x86/entry/common.c:285
 entry_SYSCALL64_slow_path+0x25/0x25 arch/x86/entry/entry_64.S:246
RIP: 0033:0x401300
RSP: 002b:00007ffc3b0e6d58 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002b0 RCX: 0000000000401300
RDX: 0000000000000000 RSI: 00007ffc3b0e6d80 RDI: 0000000000000003
RBP: 00007ffc3b0e6e00 R08: 000000000000000b R09: 0000000000000004
R10: 000000000000000d R11: 0000000000000246 R12: 0000000000000000
R13: 00000000004065a0 R14: 0000000000406630 R15: 0000000000000000
origin: 000000008fe00056
 save_stack_trace+0x59/0x60 arch/x86/kernel/stacktrace.c:59
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:352
 kmsan_internal_poison_shadow+0xb1/0x1a0 mm/kmsan/kmsan.c:247
 kmsan_poison_shadow+0x6d/0xc0 mm/kmsan/kmsan.c:260
 slab_alloc_node mm/slub.c:2743
 __kmalloc_node_track_caller+0x1f4/0x390 mm/slub.c:4349
 __kmalloc_reserve net/core/skbuff.c:138
 __alloc_skb+0x2cd/0x740 net/core/skbuff.c:231
 alloc_skb ./include/linux/skbuff.h:933
 netlink_alloc_large_skb net/netlink/af_netlink.c:1144
 netlink_sendmsg+0x934/0x10f0 net/netlink/af_netlink.c:1819
 sock_sendmsg_nosec net/socket.c:633
 sock_sendmsg net/socket.c:643
 ___sys_sendmsg+0xd4b/0x10f0 net/socket.c:1997
 __sys_sendmsg net/socket.c:2031
 SYSC_sendmsg+0x2c6/0x3f0 net/socket.c:2042
 SyS_sendmsg+0x87/0xb0 net/socket.c:2038
 do_syscall_64+0x102/0x150 arch/x86/entry/common.c:285
 return_from_SYSCALL_64+0x0/0x6a arch/x86/entry/entry_64.S:246
==================================================================

and the reproducer:

==================================================================
  #include <sys/socket.h>
  #include <net/if_arp.h>
  #include <linux/netlink.h>
  #include <stdint.h>

  int main()
  {
    int sock = socket(PF_NETLINK, SOCK_DGRAM | SOCK_NONBLOCK, 0);
    struct msghdr msg;
    memset(&msg, 0, sizeof(msg));
    char nlmsg_buf[32];
    memset(nlmsg_buf, 0, sizeof(nlmsg_buf));
    struct nlmsghdr *nlmsg = nlmsg_buf;
    nlmsg->nlmsg_len = 0x11;
    nlmsg->nlmsg_type = 0x1e; // RTM_NEWROUTE = RTM_BASE + 0x0e
    // type = 0x0e = 1110b
    // kind = 2
    nlmsg->nlmsg_flags = 0x101; // NLM_F_ROOT | NLM_F_REQUEST
    nlmsg->nlmsg_seq = 0;
    nlmsg->nlmsg_pid = 0;
    nlmsg_buf[16] = (char)7;
    struct iovec iov;
    iov.iov_base = nlmsg_buf;
    iov.iov_len = 17;
    msg.msg_iov = &iov;
    msg.msg_iovlen = 1;
    sendmsg(sock, &msg, 0);
    return 0;
  }
==================================================================

Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-24 15:27:16 -04:00
c6cd850d65 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-05-18 16:11:32 -04:00
0cd2950357 net: make struct net_device::tx_queue_len unsigned int
4 billion packet queue is something unthinkable so use 32-bit value
for now.

Space savings on x86_64:

	add/remove: 0/0 grow/shrink: 3/70 up/down: 16/-131 (-115)
	function                                     old     new   delta
	change_tx_queue_len                           94     108     +14
	qdisc_create                                1176    1177      +1
	alloc_netdev_mqs                            1124    1125      +1
	xenvif_alloc                                 533     532      -1
	x25_asy_setup                                167     166      -1
			...
	tun_queue_resize                             945     940      -5
	pfifo_fast_enqueue                           167     162      -5
	qfq_init_qdisc                               168     158     -10
	tap_queue_resize                             810     799     -11
	transmit                                     719     698     -21

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-18 10:19:30 -04:00
f6c5775ff0 net: Improve handling of failures on link and route dumps
In general, rtnetlink dumps do not anticipate failure to dump a single
object (e.g., link or route) on a single pass. As both route and link
objects have grown via more attributes, that is no longer a given.

netlink dumps can handle a failure if the dump function returns an
error; specifically, netlink_dump adds the return code to the response
if it is <= 0 so userspace is notified of the failure. The missing
piece is the rtnetlink dump functions returning the error.

Fix route and link dump functions to return the errors if no object is
added to an skb (detected by skb->len != 0). IPv6 route dumps
(rt6_dump_route) already return the error; this patch updates IPv4 and
link dumps. Other dump functions may need to be ajusted as well.

Reported-by: Jan Moskyto Matejka <mq@ucw.cz>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-16 14:54:11 -04:00
d67b9cd28c xdp: refine xdp api with regards to generic xdp
While working on the iproute2 generic XDP frontend, I noticed that
as of right now it's possible to have native *and* generic XDP
programs loaded both at the same time for the case when a driver
supports native XDP.

The intended model for generic XDP from b5cdae3291 ("net: Generic
XDP") is, however, that only one out of the two can be present at
once which is also indicated as such in the XDP netlink dump part.
The main rationale for generic XDP is to ease accessibility (in
case a driver does not yet have XDP support) and to generically
provide a semantical model as an example for driver developers
wanting to add XDP support. The generic XDP option for an XDP
aware driver can still be useful for comparing and testing both
implementations.

However, it is not intended to have a second XDP processing stage
or layer with exactly the same functionality of the first native
stage. Only reason could be to have a partial fallback for future
XDP features that are not supported yet in the native implementation
and we probably also shouldn't strive for such fallback and instead
encourage native feature support in the first place. Given there's
currently no such fallback issue or use case, lets not go there yet
if we don't need to.

Therefore, change semantics for loading XDP and bail out if the
user tries to load a generic XDP program when a native one is
present and vice versa. Another alternative to bailing out would
be to handle the transition from one flavor to another gracefully,
but that would require to bring the device down, exchange both
types of programs, and bring it up again in order to avoid a tiny
window where a packet could hit both hooks. Given this complicates
the logic for just a debugging feature in the native case, I went
with the simpler variant.

For the dump, remove IFLA_XDP_FLAGS that was added with b5cdae3291
and reuse IFLA_XDP_ATTACHED for indicating the mode. Dumping all
or just a subset of flags that were used for loading the XDP prog
is suboptimal in the long run since not all flags are useful for
dumping and if we start to reuse the same flag definitions for
load and dump, then we'll waste bit space. What we really just
want is to dump the mode for now.

Current IFLA_XDP_ATTACHED semantics are: nothing was installed (0),
a program is running at the native driver layer (1). Thus, add a
mode that says that a program is running at generic XDP layer (2).
Applications will handle this fine in that older binaries will
just indicate that something is attached at XDP layer, effectively
this is similar to IFLA_XDP_FLAGS attr that we would have had
modulo the redundancy.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-11 21:30:57 -04:00