linux-stable.git/net/core/dev.c, branch linux-3.18.y

net-gro: reset skb->pkt_type in napi_reuse_skb()

2018-11-27T15:05:36+00:00

[ Upstream commit 33d9a2c72f086cbf1087b2fd2d1a15aa9df14a7f ]

eth_type_trans() assumes initial value for skb->pkt_type
is PACKET_HOST.

This is indeed the value right after a fresh skb allocation.

However, it is possible that GRO merged a packet with a different
value (like PACKET_OTHERHOST in case macvlan is used), so
we need to make sure napi->skb will have pkt_type set back to
PACKET_HOST.

Otherwise, valid packets might be dropped by the stack because
their pkt_type is not PACKET_HOST.

napi_reuse_skb() was added in commit 96e93eab2033 ("gro: Add
internal interfaces for VLAN"), but this bug always has
been there.

Fixes: 96e93eab2033 ("gro: Add internal interfaces for VLAN")
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: propagate dev_get_valid_name return code

2018-08-28T05:21:33+00:00

[ Upstream commit 7892bd081045222b9e4027fec279a28d6fe7aa66 ]

if dev_get_valid_name failed, propagate its return code

and remove the setting err to ENODEV, it will be set to
0 again before dev_change_net_namespace exits.

Signed-off-by: Li RongQing 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

net: fool proof dev_valid_name()

2018-04-13T17:52:24+00:00

[ Upstream commit a9d48205d0aedda021fc3728972a9e9934c2b9de ]

We want to use dev_valid_name() to validate tunnel names,
so better use strnlen(name, IFNAMSIZ) than strlen(name) to make
sure to not upset KASAN.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: fix possible out-of-bound read in skb_network_protocol()

2018-04-13T17:52:23+00:00

[ Upstream commit 1dfe82ebd7d8fd43dba9948fdfb31f145014baa0 ]

skb mac header is not necessarily set at the time skb_network_protocol()
is called. Use skb->data instead.

BUG: KASAN: slab-out-of-bounds in skb_network_protocol+0x46b/0x4b0 net/core/dev.c:2739
Read of size 2 at addr ffff8801b3097a0b by task syz-executor5/14242

CPU: 1 PID: 14242 Comm: syz-executor5 Not tainted 4.16.0-rc6+ #280
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x24d lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x23c/0x360 mm/kasan/report.c:412
 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report.c:443
 skb_network_protocol+0x46b/0x4b0 net/core/dev.c:2739
 harmonize_features net/core/dev.c:2924 [inline]
 netif_skb_features+0x509/0x9b0 net/core/dev.c:3011
 validate_xmit_skb+0x81/0xb00 net/core/dev.c:3084
 validate_xmit_skb_list+0xbf/0x120 net/core/dev.c:3142
 packet_direct_xmit+0x117/0x790 net/packet/af_packet.c:256
 packet_snd net/packet/af_packet.c:2944 [inline]
 packet_sendmsg+0x3aed/0x60b0 net/packet/af_packet.c:2969
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:639
 ___sys_sendmsg+0x767/0x8b0 net/socket.c:2047
 __sys_sendmsg+0xe5/0x210 net/socket.c:2081

Fixes: 19acc327258a ("gso: Handle Trans-Ether-Bridging protocol in skb_network_protocol()")
Signed-off-by: Eric Dumazet 
Cc: Pravin B Shelar 
Reported-by: Reported-by: syzbot 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: fix race on decreasing number of TX queues

2018-03-11T15:12:18+00:00

[ Upstream commit ac5b70198adc25c73fba28de4f78adcee8f6be0b ]

netif_set_real_num_tx_queues() can be called when netdev is up.
That usually happens when user requests change of number of
channels/rings with ethtool -L.  The procedure for changing
the number of queues involves resetting the qdiscs and setting
dev->num_tx_queues to the new value.  When the new value is
lower than the old one, extra care has to be taken to ensure
ordering of accesses to the number of queues vs qdisc reset.

Currently the queues are reset before new dev->num_tx_queues
is assigned, leaving a window of time where packets can be
enqueued onto the queues going down, leading to a likely
crash in the drivers, since most drivers don't check if TX
skbs are assigned to an active queue.

Fixes: e6484930d7c7 ("net: allocate tx queues in register_netdevice")
Signed-off-by: Jakub Kicinski 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: avoid skb_warn_bad_offload on IS_ERR

2018-02-25T10:01:18+00:00

commit 8d74e9f88d65af8bb2e095aff506aa6eac755ada upstream.

skb_warn_bad_offload warns when packets enter the GSO stack that
require skb_checksum_help or vice versa. Do not warn on arbitrary
bad packets. Packet sockets can craft many. Syzkaller was able to
demonstrate another one with eth_type games.

In particular, suppress the warning when segmentation returns an
error, which is for reasons other than checksum offload.

See also commit 36c92474498a ("net: WARN if skb_checksum_help() is
called on skb requiring segmentation") for context on this warning.

Signed-off-by: Willem de Bruijn 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: qdisc_pkt_len_init() should be more robust

2018-01-31T13:46:15+00:00

[ Upstream commit 7c68d1a6b4db9012790af7ac0f0fdc0d2083422a ]

Without proper validation of DODGY packets, we might very well
feed qdisc_pkt_len_init() with invalid GSO packets.

tcp_hdrlen() might access out-of-bound data, so let's use
skb_header_pointer() and proper checks.

Whole story is described in commit d0c081b49137 ("flow_dissector:
properly cap thoff field")

We have the goal of validating DODGY packets earlier in the stack,
so we might very well revert this fix in the future.

Signed-off-by: Eric Dumazet 
Cc: Willem de Bruijn 
Cc: Jason Wang 
Reported-by: syzbot+9da69ebac7dddd804552@syzkaller.appspotmail.com
Acked-by: Jason Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: Resend IGMP memberships upon peer notification.

2017-12-20T09:01:30+00:00

[ Upstream commit 37c343b4f4e70e9dc328ab04903c0ec8d154c1a4 ]

When we notify peers of potential changes,  it's also good to update
IGMP memberships.  For example, during VM migration, updating IGMP
memberships will redirect existing multicast streams to the VM at the
new location.

Signed-off-by: Vladislav Yasevich 
Acked-by: Michael S. Tsirkin 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

tun: call dev_get_valid_name() before register_netdevice()

2017-11-18T10:06:30+00:00

[ Upstream commit 0ad646c81b2182f7fa67ec0c8c825e0ee165696d ]

register_netdevice() could fail early when we have an invalid
dev name, in which case ->ndo_uninit() is not called. For tun
device, this is a problem because a timer etc. are already
initialized and it expects ->ndo_uninit() to clean them up.

We could move these initializations into a ->ndo_init() so
that register_netdevice() knows better, however this is still
complicated due to the logic in tun_detach().

Therefore, I choose to just call dev_get_valid_name() before
register_netdevice(), which is quicker and much easier to audit.
And for this specific case, it is already enough.

Fixes: 96442e42429e ("tuntap: choose the txq based on rxq")
Reported-by: Dmitry Alexeev 
Cc: Jason Wang 
Cc: "Michael S. Tsirkin" 
Signed-off-by: Cong Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: core: Prevent from dereferencing null pointer when releasing SKB

2017-10-08T08:11:20+00:00

[ Upstream commit 9899886d5e8ec5b343b1efe44f185a0e68dc6454 ]

Added NULL check to make __dev_kfree_skb_irq consistent with kfree
family of functions.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=195289

Signed-off-by: Myungho Jung 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman