linux-stable.git/net, branch v4.4.210

netfilter: ipset: avoid null deref when IPSET_ATTR_LINENO is present

2020-01-14T19:03:07+00:00

commit 22dad713b8a5ff488e07b821195270672f486eb2 upstream.

The set uadt functions assume lineno is never NULL, but it is in
case of ip_set_utest().

syzkaller managed to generate a netlink message that calls this with
LINENO attr present:

general protection fault: 0000 [#1] PREEMPT SMP KASAN
RIP: 0010:hash_mac4_uadt+0x1bc/0x470 net/netfilter/ipset/ip_set_hash_mac.c:104
Call Trace:
 ip_set_utest+0x55b/0x890 net/netfilter/ipset/ip_set_core.c:1867
 nfnetlink_rcv_msg+0xcf2/0xfb0 net/netfilter/nfnetlink.c:229
 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
 nfnetlink_rcv+0x1ba/0x460 net/netfilter/nfnetlink.c:563

pass a dummy lineno storage, its easier than patching all set
implementations.

This seems to be a day-0 bug.

Cc: Jozsef Kadlecsik 
Reported-by: syzbot+34bd2369d38707f3f4a7@syzkaller.appspotmail.com
Fixes: a7b4f989a6294 ("netfilter: ipset: IP set core support")
Signed-off-by: Florian Westphal 
Acked-by: Jozsef Kadlecsik 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

netfilter: arp_tables: init netns pointer in xt_tgchk_param struct

2020-01-14T19:03:07+00:00

commit 1b789577f655060d98d20ed0c6f9fbd469d6ba63 upstream.

We get crash when the targets checkentry function tries to make
use of the network namespace pointer for arptables.

When the net pointer got added back in 2010, only ip/ip6/ebtables were
changed to initialize it, so arptables has this set to NULL.

This isn't a problem for normal arptables because no existing
arptables target has a checkentry function that makes use of par->net.

However, direct users of the setsockopt interface can provide any
target they want as long as its registered for ARP or UNPSEC protocols.

syzkaller managed to send a semi-valid arptables rule for RATEEST target
which is enough to trigger NULL deref:

kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
RIP: xt_rateest_tg_checkentry+0x11d/0xb40 net/netfilter/xt_RATEEST.c:109
[..]
 xt_check_target+0x283/0x690 net/netfilter/x_tables.c:1019
 check_target net/ipv4/netfilter/arp_tables.c:399 [inline]
 find_check_entry net/ipv4/netfilter/arp_tables.c:422 [inline]
 translate_table+0x1005/0x1d70 net/ipv4/netfilter/arp_tables.c:572
 do_replace net/ipv4/netfilter/arp_tables.c:977 [inline]
 do_arpt_set_ctl+0x310/0x640 net/ipv4/netfilter/arp_tables.c:1456

Fixes: add67461240c1d ("netfilter: add struct net * to target parameters")
Reported-by: syzbot+d7358a458d8a81aee898@syzkaller.appspotmail.com
Signed-off-by: Florian Westphal 
Acked-by: Cong Wang 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

vlan: fix memory leak in vlan_dev_set_egress_priority

2020-01-12T10:22:52+00:00

[ Upstream commit 9bbd917e0bec9aebdbd0c8dbc966caec15eb33e9 ]

There are few cases where the ndo_uninit() handler might be not
called if an error happens while device is initialized.

Since vlan_newlink() calls vlan_changelink() before
trying to register the netdevice, we need to make sure
vlan_dev_uninit() has been called at least once,
or we might leak allocated memory.

BUG: memory leak
unreferenced object 0xffff888122a206c0 (size 32):
  comm "syz-executor511", pid 7124, jiffies 4294950399 (age 32.240s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 61 73 00 00 00 00 00 00 00 00  ......as........
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<000000000eb3bb85>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline]
    [<000000000eb3bb85>] slab_post_alloc_hook mm/slab.h:586 [inline]
    [<000000000eb3bb85>] slab_alloc mm/slab.c:3320 [inline]
    [<000000000eb3bb85>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3549
    [<000000007b99f620>] kmalloc include/linux/slab.h:556 [inline]
    [<000000007b99f620>] vlan_dev_set_egress_priority+0xcc/0x150 net/8021q/vlan_dev.c:194
    [<000000007b0cb745>] vlan_changelink+0xd6/0x140 net/8021q/vlan_netlink.c:126
    [<0000000065aba83a>] vlan_newlink+0x135/0x200 net/8021q/vlan_netlink.c:181
    [<00000000fb5dd7a2>] __rtnl_newlink+0x89a/0xb80 net/core/rtnetlink.c:3305
    [<00000000ae4273a1>] rtnl_newlink+0x4e/0x80 net/core/rtnetlink.c:3363
    [<00000000decab39f>] rtnetlink_rcv_msg+0x178/0x4b0 net/core/rtnetlink.c:5424
    [<00000000accba4ee>] netlink_rcv_skb+0x61/0x170 net/netlink/af_netlink.c:2477
    [<00000000319fe20f>] rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5442
    [<00000000d51938dc>] netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
    [<00000000d51938dc>] netlink_unicast+0x223/0x310 net/netlink/af_netlink.c:1328
    [<00000000e539ac79>] netlink_sendmsg+0x2c0/0x570 net/netlink/af_netlink.c:1917
    [<000000006250c27e>] sock_sendmsg_nosec net/socket.c:639 [inline]
    [<000000006250c27e>] sock_sendmsg+0x54/0x70 net/socket.c:659
    [<00000000e2a156d1>] ____sys_sendmsg+0x2d0/0x300 net/socket.c:2330
    [<000000008c87466e>] ___sys_sendmsg+0x8a/0xd0 net/socket.c:2384
    [<00000000110e3054>] __sys_sendmsg+0x80/0xf0 net/socket.c:2417
    [<00000000d71077c8>] __do_sys_sendmsg net/socket.c:2426 [inline]
    [<00000000d71077c8>] __se_sys_sendmsg net/socket.c:2424 [inline]
    [<00000000d71077c8>] __x64_sys_sendmsg+0x23/0x30 net/socket.c:2424

Fixe: 07b5b17e157b ("[VLAN]: Use rtnl_link API")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

vlan: vlan_changelink() should propagate errors

2020-01-12T10:22:52+00:00

[ Upstream commit eb8ef2a3c50092bb018077c047b8dba1ce0e78e3 ]

Both vlan_dev_change_flags() and vlan_dev_set_egress_priority()
can return an error. vlan_changelink() should not ignore them.

Fixes: 07b5b17e157b ("[VLAN]: Use rtnl_link API")
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tcp: fix "old stuff" D-SACK causing SACK to be treated as D-SACK

2020-01-12T10:22:51+00:00

[ Upstream commit c9655008e7845bcfdaac10a1ed8554ec167aea88 ]

When we receive a D-SACK, where the sequence number satisfies:
	undo_marker <= start_seq < end_seq <= prior_snd_una
we consider this is a valid D-SACK and tcp_is_sackblock_valid()
returns true, then this D-SACK is discarded as "old stuff",
but the variable first_sack_index is not marked as negative
in tcp_sacktag_write_queue().

If this D-SACK also carries a SACK that needs to be processed
(for example, the previous SACK segment was lost), this SACK
will be treated as a D-SACK in the following processing of
tcp_sacktag_write_queue(), which will eventually lead to
incorrect updates of undo_retrans and reordering.

Fixes: fd6dad616d4f ("[TCP]: Earlier SACK block verification & simplify access to them")
Signed-off-by: Pengcheng Yang 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sctp: free cmd->obj.chunk for the unprocessed SCTP_CMD_REPLY

2020-01-12T10:22:51+00:00

[ Upstream commit be7a7729207797476b6666f046d765bdf9630407 ]

This patch is to fix a memleak caused by no place to free cmd->obj.chunk
for the unprocessed SCTP_CMD_REPLY. This issue occurs when failing to
process a cmd while there're still SCTP_CMD_REPLY cmds on the cmd seq
with an allocated chunk in cmd->obj.chunk.

So fix it by freeing cmd->obj.chunk for each SCTP_CMD_REPLY cmd left on
the cmd seq when any cmd returns error. While at it, also remove 'nomem'
label.

Reported-by: syzbot+107c4aff5f392bf1517f@syzkaller.appspotmail.com
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Xin Long 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

pkt_sched: fq: do not accept silly TCA_FQ_QUANTUM

2020-01-12T10:22:51+00:00

[ Upstream commit d9e15a2733067c9328fb56d98fe8e574fa19ec31 ]

As diagnosed by Florian :

If TCA_FQ_QUANTUM is set to 0x80000000, fq_deueue()
can loop forever in :

if (f->credit <= 0) {
  f->credit += q->quantum;
  goto begin;
}

... because f->credit is either 0 or -2147483648.

Let's limit TCA_FQ_QUANTUM to no more than 1 << 20 :
This max value should limit risks of breaking user setups
while fixing this bug.

Fixes: afe4fd062416 ("pkt_sched: fq: Fair Queue packet scheduler")
Signed-off-by: Eric Dumazet 
Diagnosed-by: Florian Westphal 
Reported-by: syzbot+dc9071cc5a85950bdfce@syzkaller.appspotmail.com
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

llc2: Fix return statement of llc_stat_ev_rx_null_dsap_xid_c (and _test_c)

2020-01-12T10:22:50+00:00

[ Upstream commit af1c0e4e00f3cc76cb136ebf2e2c04e8b6446285 ]

When a frame with NULL DSAP is received, llc_station_rcv is called.
In turn, llc_stat_ev_rx_null_dsap_xid_c is called to check if it is a NULL
XID frame. The return statement of llc_stat_ev_rx_null_dsap_xid_c returns 1
when the incoming frame is not a NULL XID frame and 0 otherwise. Hence, a
NULL XID response is returned unexpectedly, e.g. when the incoming frame is
a NULL TEST command.

To fix the error, simply remove the conditional operator.

A similar error in llc_stat_ev_rx_null_dsap_test_c is also fixed.

Signed-off-by: Chan Shu Tak, Alex 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

rfkill: Fix incorrect check to avoid NULL pointer dereference

2020-01-12T10:22:49+00:00

[ Upstream commit 6fc232db9e8cd50b9b83534de9cd91ace711b2d7 ]

In rfkill_register, the struct rfkill pointer is first derefernced
and then checked for NULL. This patch removes the BUG_ON and returns
an error to the caller in case rfkill is NULL.

Signed-off-by: Aditya Pakki 
Link: https://lore.kernel.org/r/20191215153409.21696-1-pakki001@umn.edu
Signed-off-by: Johannes Berg 
Signed-off-by: Sasha Levin

netfilter: ctnetlink: netns exit must wait for callbacks

2020-01-12T10:22:47+00:00

[ Upstream commit 18a110b022a5c02e7dc9f6109d0bd93e58ac6ebb ]

Curtis Taylor and Jon Maxwell reported and debugged a crash on 3.10
based kernel.

Crash occurs in ctnetlink_conntrack_events because net->nfnl socket is
NULL.  The nfnl socket was set to NULL by netns destruction running on
another cpu.

The exiting network namespace calls the relevant destructors in the
following order:

1. ctnetlink_net_exit_batch

This nulls out the event callback pointer in struct netns.

2. nfnetlink_net_exit_batch

This nulls net->nfnl socket and frees it.

3. nf_conntrack_cleanup_net_list

This removes all remaining conntrack entries.

This is order is correct. The only explanation for the crash so ar is:

cpu1: conntrack is dying, eviction occurs:
 -> nf_ct_delete()
   -> nf_conntrack_event_report \
     -> nf_conntrack_eventmask_report
       -> notify->fcn() (== ctnetlink_conntrack_events).

cpu1: a. fetches rcu protected pointer to obtain ctnetlink event callback.
      b. gets interrupted.
 cpu2: runs netns exit handlers:
     a runs ctnetlink destructor, event cb pointer set to NULL.
     b runs nfnetlink destructor, nfnl socket is closed and set to NULL.
cpu1: c. resumes and trips over NULL net->nfnl.

Problem appears to be that ctnetlink_net_exit_batch only prevents future
callers of nf_conntrack_eventmask_report() from obtaining the callback.
It doesn't wait of other cpus that might have already obtained the
callbacks address.

I don't see anything in upstream kernels that would prevent similar
crash: We need to wait for all cpus to have exited the event callback.

Fixes: 9592a5c01e79dbc59eb56fa ("netfilter: ctnetlink: netns support")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin