linux.git/net/core/rtnetlink.c, branch v6.6

netlink: Correct offload_xstats size

2023-10-17T00:32:59+00:00

rtnl_offload_xstats_get_size_hw_s_info_one() conditionalizes the
size-computation for IFLA_OFFLOAD_XSTATS_HW_S_INFO_USED based on whether
or not the device has offload_xstats enabled.

However, rtnl_offload_xstats_fill_hw_s_info_one() is adding the u8 for
that field uncondtionally.

syzkaller triggered a WARNING in rtnl_stats_get due to this:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 754 at net/core/rtnetlink.c:5982 rtnl_stats_get+0x2f4/0x300
Modules linked in:
CPU: 0 PID: 754 Comm: syz-executor148 Not tainted 6.6.0-rc2-g331b78eb12af #45
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
RIP: 0010:rtnl_stats_get+0x2f4/0x300 net/core/rtnetlink.c:5982
Code: ff ff 89 ee e8 7d 72 50 ff 83 fd a6 74 17 e8 33 6e 50 ff 4c 89 ef be 02 00 00 00 e8 86 00 fa ff e9 7b fe ff ff e8 1c 6e 50 ff <0f> 0b eb e5 e8 73 79 7b 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc900006837c0 EFLAGS: 00010293
RAX: ffffffff81cf7f24 RBX: ffff8881015d9000 RCX: ffff888101815a00
RDX: 0000000000000000 RSI: 00000000ffffffa6 RDI: 00000000ffffffa6
RBP: 00000000ffffffa6 R08: ffffffff81cf7f03 R09: 0000000000000001
R10: ffff888101ba47b9 R11: ffff888101815a00 R12: ffff8881017dae00
R13: ffff8881017dad00 R14: ffffc90000683ab8 R15: ffffffff83c1f740
FS:  00007fbc22dbc740(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000046 CR3: 000000010264e003 CR4: 0000000000170ef0
Call Trace:
 
 rtnetlink_rcv_msg+0x677/0x710 net/core/rtnetlink.c:6480
 netlink_rcv_skb+0xea/0x1c0 net/netlink/af_netlink.c:2545
 netlink_unicast+0x430/0x500 net/netlink/af_netlink.c:1342
 netlink_sendmsg+0x4fc/0x620 net/netlink/af_netlink.c:1910
 sock_sendmsg+0xa8/0xd0 net/socket.c:730
 ____sys_sendmsg+0x22a/0x320 net/socket.c:2541
 ___sys_sendmsg+0x143/0x190 net/socket.c:2595
 __x64_sys_sendmsg+0xd8/0x150 net/socket.c:2624
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x47/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x6e/0xd8
RIP: 0033:0x7fbc22e8d6a9
Code: 5c c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 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 73 01 c3 48 8b 0d 4f 37 0d 00 f7 d8 64 89 01 48
RSP: 002b:00007ffc4320e778 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004007d0 RCX: 00007fbc22e8d6a9
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 0000000000000001 R08: 0000000000000000 R09: 00000000004007d0
R10: 0000000000000008 R11: 0000000000000246 R12: 00007ffc4320e898
R13: 00007ffc4320e8a8 R14: 00000000004004a0 R15: 00007fbc22fa5a80
 
---[ end trace 0000000000000000 ]---

Which didn't happen prior to commit bf9f1baa279f ("net: add dedicated
kmem_cache for typical/small skb->head") as the skb always was large
enough.

Fixes: 0e7788fd7622 ("net: rtnetlink: Add UAPI for obtaining L3 offload xstats")
Signed-off-by: Christoph Paasch 
Reviewed-by: Petr Machata 
Link: https://lore.kernel.org/r/20231013041448.8229-1-cpaasch@apple.com
Signed-off-by: Jakub Kicinski

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

2023-08-24T17:51:39+00:00

Cross-merge networking fixes after downstream PR.

Conflicts:

include/net/inet_sock.h
  f866fbc842de ("ipv4: fix data-races around inet->inet_id")
  c274af224269 ("inet: introduce inet->inet_flags")
https://lore.kernel.org/all/679ddff6-db6e-4ff6-b177-574e90d0103d@tessares.net/

Adjacent changes:

drivers/net/bonding/bond_alb.c
  e74216b8def3 ("bonding: fix macvlan over alb bond support")
  f11e5bd159b0 ("bonding: support balance-alb with openvswitch")

drivers/net/ethernet/broadcom/bgmac.c
  d6499f0b7c7c ("net: bgmac: Return PTR_ERR() for fixed_phy_register()")
  23a14488ea58 ("net: bgmac: Fix return value check for fixed_phy_register()")

drivers/net/ethernet/broadcom/genet/bcmmii.c
  32bbe64a1386 ("net: bcmgenet: Fix return value check for fixed_phy_register()")
  acf50d1adbf4 ("net: bcmgenet: Return PTR_ERR() for fixed_phy_register()")

net/sctp/socket.c
  f866fbc842de ("ipv4: fix data-races around inet->inet_id")
  b09bde5c3554 ("inet: move inet->mc_loop to inet->inet_frags")

Signed-off-by: Jakub Kicinski

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

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

2023-08-03T21:34:37+00:00

Cross-merge networking fixes after downstream PR.

Conflicts:

net/dsa/port.c
  9945c1fb03a3 ("net: dsa: fix older DSA drivers using phylink")
  a88dd7538461 ("net: dsa: remove legacy_pre_march2020 detection")
https://lore.kernel.org/all/20230731102254.2c9868ca@canb.auug.org.au/

net/xdp/xsk.c
  3c5b4d69c358 ("net: annotate data-races around sk->sk_mark")
  b7f72a30e9ac ("xsk: introduce wrappers and helpers for supporting multi-buffer in Tx path")
https://lore.kernel.org/all/20230731102631.39988412@canb.auug.org.au/

drivers/net/ethernet/broadcom/bnxt/bnxt.c
  37b61cda9c16 ("bnxt: don't handle XDP in netpoll")
  2b56b3d99241 ("eth: bnxt: handle invalid Tx completions more gracefully")
https://lore.kernel.org/all/20230801101708.1dc7faac@canb.auug.org.au/

Adjacent changes:

drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_fs.c
  62da08331f1a ("net/mlx5e: Set proper IPsec source port in L4 selector")
  fbd517549c32 ("net/mlx5e: Add function to get IPsec offload namespace")

drivers/net/ethernet/sfc/selftest.c
  55c1528f9b97 ("sfc: fix field-spanning memcpy in selftest")
  ae9d445cd41f ("sfc: Miscellaneous comment removals")

Signed-off-by: Jakub Kicinski

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

bridge: Add backup nexthop ID support

2023-07-19T09:53:49+00:00

Add a new bridge port attribute that allows attaching a nexthop object
ID to an skb that is redirected to a backup bridge port with VLAN
tunneling enabled.

Specifically, when redirecting a known unicast packet, read the backup
nexthop ID from the bridge port that lost its carrier and set it in the
bridge control block of the skb before forwarding it via the backup
port. Note that reading the ID from the bridge port should not result in
a cache miss as the ID is added next to the 'backup_port' field that was
already accessed. After this change, the 'state' field still stays on
the first cache line, together with other data path related fields such
as 'flags and 'vlgrp':

struct net_bridge_port {
        struct net_bridge *        br;                   /*     0     8 */
        struct net_device *        dev;                  /*     8     8 */
        netdevice_tracker          dev_tracker;          /*    16     0 */
        struct list_head           list;                 /*    16    16 */
        long unsigned int          flags;                /*    32     8 */
        struct net_bridge_vlan_group * vlgrp;            /*    40     8 */
        struct net_bridge_port *   backup_port;          /*    48     8 */
        u32                        backup_nhid;          /*    56     4 */
        u8                         priority;             /*    60     1 */
        u8                         state;                /*    61     1 */
        u16                        port_no;              /*    62     2 */
        /* --- cacheline 1 boundary (64 bytes) --- */
[...]
} __attribute__((__aligned__(8)));

When forwarding an skb via a bridge port that has VLAN tunneling
enabled, check if the backup nexthop ID stored in the bridge control
block is valid (i.e., not zero). If so, instead of attaching the
pre-allocated metadata (that only has the tunnel key set), allocate a
new metadata, set both the tunnel key and the nexthop object ID and
attach it to the skb.

By default, do not dump the new attribute to user space as a value of
zero is an invalid nexthop object ID.

The above is useful for EVPN multihoming. When one of the links
composing an Ethernet Segment (ES) fails, traffic needs to be redirected
towards the host via one of the other ES peers. For example, if a host
is multihomed to three different VTEPs, the backup port of each ES link
needs to be set to the VXLAN device and the backup nexthop ID needs to
point to an FDB nexthop group that includes the IP addresses of the
other two VTEPs. The VXLAN driver will extract the ID from the metadata
of the redirected skb, calculate its flow hash and forward it towards
one of the other VTEPs. If the ID does not exist, or represents an
invalid nexthop object, the VXLAN driver will drop the skb. This
relieves the bridge driver from the need to validate the ID.

Signed-off-by: Ido Schimmel 
Acked-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

rtnetlink: Move nesting cancellation rollback to proper function

2023-07-18T13:14:05+00:00

Make rtnl_fill_vf() cancel the vfinfo attribute on error instead of the
inner rtnl_fill_vfinfo(), as it is the function that starts it.

Signed-off-by: Gal Pressman 
Link: https://lore.kernel.org/r/20230716072440.2372567-1-gal@nvidia.com
Signed-off-by: Paolo Abeni

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