linux-stable.git/net/core/rtnetlink.c, branch v6.5

rtnetlink: Reject negative ifindexes in RTM_NEWLINK

2023-08-24T07:45:52+00:00

Negative ifindexes are illegal, but the kernel does not validate the
ifindex in the ancillary header of RTM_NEWLINK messages, resulting in
the kernel generating a warning [1] when such an ifindex is specified.

Fix by rejecting negative ifindexes.

[1]
WARNING: CPU: 0 PID: 5031 at net/core/dev.c:9593 dev_index_reserve+0x1a2/0x1c0 net/core/dev.c:9593
[...]
Call Trace:
 
 register_netdevice+0x69a/0x1490 net/core/dev.c:10081
 br_dev_newlink+0x27/0x110 net/bridge/br_netlink.c:1552
 rtnl_newlink_create net/core/rtnetlink.c:3471 [inline]
 __rtnl_newlink+0x115e/0x18c0 net/core/rtnetlink.c:3688
 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3701
 rtnetlink_rcv_msg+0x439/0xd30 net/core/rtnetlink.c:6427
 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2545
 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
 netlink_unicast+0x536/0x810 net/netlink/af_netlink.c:1368
 netlink_sendmsg+0x93c/0xe40 net/netlink/af_netlink.c:1910
 sock_sendmsg_nosec net/socket.c:728 [inline]
 sock_sendmsg+0xd9/0x180 net/socket.c:751
 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2538
 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2592
 __sys_sendmsg+0x117/0x1e0 net/socket.c:2621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: 38f7b870d4a6 ("[RTNETLINK]: Link creation API")
Reported-by: syzbot+5ba06978f34abb058571@syzkaller.appspotmail.com
Signed-off-by: Ido Schimmel 
Reviewed-by: Jiri Pirko 
Reviewed-by: Jakub Kicinski 
Link: https://lore.kernel.org/r/20230823064348.2252280-1-idosch@nvidia.com
Signed-off-by: Paolo Abeni

net: validate veth and vxcan peer ifindexes

2023-08-20T10:40:03+00:00

veth and vxcan need to make sure the ifindexes of the peer
are not negative, core does not validate this.

Using iproute2 with user-space-level checking removed:

Before:

  # ./ip link add index 10 type veth peer index -1
  # ip link show
  1: lo:  mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
  2: enp1s0:  mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000
    link/ether 52:54:00:74:b2:03 brd ff:ff:ff:ff:ff:ff
  10: veth1@veth0:  mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether 8a:90:ff:57:6d:5d brd ff:ff:ff:ff:ff:ff
  -1: veth0@veth1:  mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether ae:ed:18:e6:fa:7f brd ff:ff:ff:ff:ff:ff

Now:

  $ ./ip link add index 10 type veth peer index -1
  Error: ifindex can't be negative.

This problem surfaced in net-next because an explicit WARN()
was added, the root cause is older.

Fixes: e6f8f1a739b6 ("veth: Allow to create peer link with given ifindex")
Fixes: a8f820a380a2 ("can: add Virtual CAN Tunnel driver (vxcan)")
Reported-by: syzbot+5ba06978f34abb058571@syzkaller.appspotmail.com
Signed-off-by: Jakub Kicinski 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller

rtnetlink: let rtnl_bridge_setlink checks IFLA_BRIDGE_MODE length

2023-07-28T00:14:01+00:00

There are totally 9 ndo_bridge_setlink handlers in the current kernel,
which are 1) bnxt_bridge_setlink, 2) be_ndo_bridge_setlink 3)
i40e_ndo_bridge_setlink 4) ice_bridge_setlink 5)
ixgbe_ndo_bridge_setlink 6) mlx5e_bridge_setlink 7)
nfp_net_bridge_setlink 8) qeth_l2_bridge_setlink 9) br_setlink.

By investigating the code, we find that 1-7 parse and use nlattr
IFLA_BRIDGE_MODE but 3 and 4 forget to do the nla_len check. This can
lead to an out-of-attribute read and allow a malformed nlattr (e.g.,
length 0) to be viewed as a 2 byte integer.

To avoid such issues, also for other ndo_bridge_setlink handlers in the
future. This patch adds the nla_len check in rtnl_bridge_setlink and
does an early error return if length mismatches. To make it works, the
break is removed from the parsing for IFLA_BRIDGE_FLAGS to make sure
this nla_for_each_nested iterates every attribute.

Fixes: b1edc14a3fbf ("ice: Implement ice_bridge_getlink and ice_bridge_setlink")
Fixes: 51616018dd1b ("i40e: Add support for getlink, setlink ndo ops")
Suggested-by: Jakub Kicinski 
Signed-off-by: Lin Ma 
Acked-by: Nikolay Aleksandrov 
Reviewed-by: Hangbin Liu 
Link: https://lore.kernel.org/r/20230726075314.1059224-1-linma@zju.edu.cn
Signed-off-by: Jakub Kicinski

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

2023-06-27T16:45:22+00:00

Merge in late fixes to prepare for the 6.5 net-next PR.

Signed-off-by: Jakub Kicinski

netlink: do not hard code device address lenth in fdb dumps

2023-06-23T02:36:58+00:00

syzbot reports that some netdev devices do not have a six bytes
address [1]

Replace ETH_ALEN by dev->addr_len.

[1] (Case of a device where dev->addr_len = 4)

BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in copyout+0xb8/0x100 lib/iov_iter.c:169
instrument_copy_to_user include/linux/instrumented.h:114 [inline]
copyout+0xb8/0x100 lib/iov_iter.c:169
_copy_to_iter+0x6d8/0x1d00 lib/iov_iter.c:536
copy_to_iter include/linux/uio.h:206 [inline]
simple_copy_to_iter+0x68/0xa0 net/core/datagram.c:513
__skb_datagram_iter+0x123/0xdc0 net/core/datagram.c:419
skb_copy_datagram_iter+0x5c/0x200 net/core/datagram.c:527
skb_copy_datagram_msg include/linux/skbuff.h:3960 [inline]
netlink_recvmsg+0x4ae/0x15a0 net/netlink/af_netlink.c:1970
sock_recvmsg_nosec net/socket.c:1019 [inline]
sock_recvmsg net/socket.c:1040 [inline]
____sys_recvmsg+0x283/0x7f0 net/socket.c:2722
___sys_recvmsg+0x223/0x840 net/socket.c:2764
do_recvmmsg+0x4f9/0xfd0 net/socket.c:2858
__sys_recvmmsg net/socket.c:2937 [inline]
__do_sys_recvmmsg net/socket.c:2960 [inline]
__se_sys_recvmmsg net/socket.c:2953 [inline]
__x64_sys_recvmmsg+0x397/0x490 net/socket.c:2953
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was stored to memory at:
__nla_put lib/nlattr.c:1009 [inline]
nla_put+0x1c6/0x230 lib/nlattr.c:1067
nlmsg_populate_fdb_fill+0x2b8/0x600 net/core/rtnetlink.c:4071
nlmsg_populate_fdb net/core/rtnetlink.c:4418 [inline]
ndo_dflt_fdb_dump+0x616/0x840 net/core/rtnetlink.c:4456
rtnl_fdb_dump+0x14ff/0x1fc0 net/core/rtnetlink.c:4629
netlink_dump+0x9d1/0x1310 net/netlink/af_netlink.c:2268
netlink_recvmsg+0xc5c/0x15a0 net/netlink/af_netlink.c:1995
sock_recvmsg_nosec+0x7a/0x120 net/socket.c:1019
____sys_recvmsg+0x664/0x7f0 net/socket.c:2720
___sys_recvmsg+0x223/0x840 net/socket.c:2764
do_recvmmsg+0x4f9/0xfd0 net/socket.c:2858
__sys_recvmmsg net/socket.c:2937 [inline]
__do_sys_recvmmsg net/socket.c:2960 [inline]
__se_sys_recvmmsg net/socket.c:2953 [inline]
__x64_sys_recvmmsg+0x397/0x490 net/socket.c:2953
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
slab_post_alloc_hook+0x12d/0xb60 mm/slab.h:716
slab_alloc_node mm/slub.c:3451 [inline]
__kmem_cache_alloc_node+0x4ff/0x8b0 mm/slub.c:3490
kmalloc_trace+0x51/0x200 mm/slab_common.c:1057
kmalloc include/linux/slab.h:559 [inline]
__hw_addr_create net/core/dev_addr_lists.c:60 [inline]
__hw_addr_add_ex+0x2e5/0x9e0 net/core/dev_addr_lists.c:118
__dev_mc_add net/core/dev_addr_lists.c:867 [inline]
dev_mc_add+0x9a/0x130 net/core/dev_addr_lists.c:885
igmp6_group_added+0x267/0xbc0 net/ipv6/mcast.c:680
ipv6_mc_up+0x296/0x3b0 net/ipv6/mcast.c:2754
ipv6_mc_remap+0x1e/0x30 net/ipv6/mcast.c:2708
addrconf_type_change net/ipv6/addrconf.c:3731 [inline]
addrconf_notify+0x4d3/0x1d90 net/ipv6/addrconf.c:3699
notifier_call_chain kernel/notifier.c:93 [inline]
raw_notifier_call_chain+0xe4/0x430 kernel/notifier.c:461
call_netdevice_notifiers_info net/core/dev.c:1935 [inline]
call_netdevice_notifiers_extack net/core/dev.c:1973 [inline]
call_netdevice_notifiers+0x1ee/0x2d0 net/core/dev.c:1987
bond_enslave+0xccd/0x53f0 drivers/net/bonding/bond_main.c:1906
do_set_master net/core/rtnetlink.c:2626 [inline]
rtnl_newlink_create net/core/rtnetlink.c:3460 [inline]
__rtnl_newlink net/core/rtnetlink.c:3660 [inline]
rtnl_newlink+0x378c/0x40e0 net/core/rtnetlink.c:3673
rtnetlink_rcv_msg+0x16a6/0x1840 net/core/rtnetlink.c:6395
netlink_rcv_skb+0x371/0x650 net/netlink/af_netlink.c:2546
rtnetlink_rcv+0x34/0x40 net/core/rtnetlink.c:6413
netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
netlink_unicast+0xf28/0x1230 net/netlink/af_netlink.c:1365
netlink_sendmsg+0x122f/0x13d0 net/netlink/af_netlink.c:1913
sock_sendmsg_nosec net/socket.c:724 [inline]
sock_sendmsg net/socket.c:747 [inline]
____sys_sendmsg+0x999/0xd50 net/socket.c:2503
___sys_sendmsg+0x28d/0x3c0 net/socket.c:2557
__sys_sendmsg net/socket.c:2586 [inline]
__do_sys_sendmsg net/socket.c:2595 [inline]
__se_sys_sendmsg net/socket.c:2593 [inline]
__x64_sys_sendmsg+0x304/0x490 net/socket.c:2593
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

Bytes 2856-2857 of 3500 are uninitialized
Memory access of size 3500 starts at ffff888018d99104
Data copied to user address 0000000020000480

Fixes: d83b06036048 ("net: add fdb generic dump routine")
Reported-by: syzbot 
Signed-off-by: Eric Dumazet 
Reviewed-by: Jiri Pirko 
Link: https://lore.kernel.org/r/20230621174720.1845040-1-edumazet@google.com
Signed-off-by: Jakub Kicinski

rtnetlink: move validate_linkmsg out of do_setlink

2023-06-15T05:34:13+00:00

This patch moves validate_linkmsg() out of do_setlink() to its callers
and deletes the early validate_linkmsg() call in __rtnl_newlink(), so
that it will not call validate_linkmsg() twice in either of the paths:

  - __rtnl_newlink() -> do_setlink()
  - __rtnl_newlink() -> rtnl_newlink_create() -> rtnl_create_link()

Additionally, as validate_linkmsg() is now only called with a real
dev, we can remove the NULL check for dev in validate_linkmsg().

Note that we moved validate_linkmsg() check to the places where it has
not done any changes to the dev, as Jakub suggested.

Signed-off-by: Xin Long 
Reviewed-by: Simon Horman 
Link: https://lore.kernel.org/r/cf2ef061e08251faf9e8be25ff0d61150c030475.1686585334.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski

rtnetlink: extend RTEXT_FILTER_SKIP_STATS to IFLA_VF_INFO

2023-06-14T11:28:26+00:00

This filter already exists for excluding IPv6 SNMP stats. Extend its
definition to also exclude IFLA_VF_INFO stats in RTM_GETLINK.

This patch constitutes a partial fix for a netlink attribute nesting
overflow bug in IFLA_VFINFO_LIST. By excluding the stats when the
requester doesn't need them, the truncation of the VF list is avoided.

While it was technically only the stats added in commit c5a9f6f0ab40
("net/core: Add drop counters to VF statistics") breaking the camel's
back, the appreciable size of the stats data should never have been
included without due consideration for the maximum number of VFs
supported by PCI.

Fixes: 3b766cd83232 ("net/core: Add reading VF statistics through the PF netdevice")
Fixes: c5a9f6f0ab40 ("net/core: Add drop counters to VF statistics")
Signed-off-by: Edwin Peer 
Cc: Edwin Peer 
Signed-off-by: Gal Pressman 
Link: https://lore.kernel.org/r/20230611105108.122586-1-gal@nvidia.com
Signed-off-by: Paolo Abeni

rtnetlink: add the missing IFLA_GRO_ tb check in validate_linkmsg

2023-06-01T16:59:44+00:00

This fixes the issue that dev gro_max_size and gso_ipv4_max_size
can be set to a huge value:

  # ip link add dummy1 type dummy
  # ip link set dummy1 gro_max_size 4294967295
  # ip -d link show dummy1
    dummy addrgenmode eui64 ... gro_max_size 4294967295

Fixes: 0fe79f28bfaf ("net: allow gro_max_size to exceed 65536")
Fixes: 9eefedd58ae1 ("net: add gso_ipv4_max_size and gro_ipv4_max_size per device")
Reported-by: Xiumei Mu 
Signed-off-by: Xin Long 
Reviewed-by: Simon Horman 
Signed-off-by: Jakub Kicinski

rtnetlink: move IFLA_GSO_ tb check to validate_linkmsg

2023-06-01T16:59:44+00:00

These IFLA_GSO_* tb check should also be done for the new created link,
otherwise, they can be set to a huge value when creating links:

  # ip link add dummy1 gso_max_size 4294967295 type dummy
  # ip -d link show dummy1
    dummy addrgenmode eui64 ... gso_max_size 4294967295

Fixes: 46e6b992c250 ("rtnetlink: allow GSO maximums to be set on device creation")
Fixes: 9eefedd58ae1 ("net: add gso_ipv4_max_size and gro_ipv4_max_size per device")
Signed-off-by: Xin Long 
Reviewed-by: Simon Horman 
Signed-off-by: Jakub Kicinski

rtnetlink: call validate_linkmsg in rtnl_create_link

2023-06-01T16:59:43+00:00

validate_linkmsg() was introduced by commit 1840bb13c22f5b ("[RTNL]:
Validate hardware and broadcast address attribute for RTM_NEWLINK")
to validate tb[IFLA_ADDRESS/BROADCAST] for existing links. The same
check should also be done for newly created links.

This patch adds validate_linkmsg() call in rtnl_create_link(), to
avoid the invalid address set when creating some devices like:

  # ip link add dummy0 type dummy
  # ip link add link dummy0 name mac0 address 01:02 type macsec

Fixes: 0e06877c6fdb ("[RTNETLINK]: rtnl_link: allow specifying initial device address")
Signed-off-by: Xin Long 
Reviewed-by: Simon Horman 
Signed-off-by: Jakub Kicinski