linux-stable.git/net/core, branch v5.1.3

flow_dissector: disable preemption around BPF calls

2019-05-16T17:35:38+00:00

[ Upstream commit b1c17a9a353878602fd5bfe9103e4afe5e9a3f96 ]

Various things in eBPF really require us to disable preemption
before running an eBPF program.

syzbot reported :

BUG: assuming atomic context at net/core/flow_dissector.c:737
in_atomic(): 0, irqs_disabled(): 0, pid: 24710, name: syz-executor.3
2 locks held by syz-executor.3/24710:
 #0: 00000000e81a4bf1 (&tfile->napi_mutex){+.+.}, at: tun_get_user+0x168e/0x3ff0 drivers/net/tun.c:1850
 #1: 00000000254afebd (rcu_read_lock){....}, at: __skb_flow_dissect+0x1e1/0x4bb0 net/core/flow_dissector.c:822
CPU: 1 PID: 24710 Comm: syz-executor.3 Not tainted 5.1.0+ #6
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+0x172/0x1f0 lib/dump_stack.c:113
 __cant_sleep kernel/sched/core.c:6165 [inline]
 __cant_sleep.cold+0xa3/0xbb kernel/sched/core.c:6142
 bpf_flow_dissect+0xfe/0x390 net/core/flow_dissector.c:737
 __skb_flow_dissect+0x362/0x4bb0 net/core/flow_dissector.c:853
 skb_flow_dissect_flow_keys_basic include/linux/skbuff.h:1322 [inline]
 skb_probe_transport_header include/linux/skbuff.h:2500 [inline]
 skb_probe_transport_header include/linux/skbuff.h:2493 [inline]
 tun_get_user+0x2cfe/0x3ff0 drivers/net/tun.c:1940
 tun_chr_write_iter+0xbd/0x156 drivers/net/tun.c:2037
 call_write_iter include/linux/fs.h:1872 [inline]
 do_iter_readv_writev+0x5fd/0x900 fs/read_write.c:693
 do_iter_write fs/read_write.c:970 [inline]
 do_iter_write+0x184/0x610 fs/read_write.c:951
 vfs_writev+0x1b3/0x2f0 fs/read_write.c:1015
 do_writev+0x15b/0x330 fs/read_write.c:1058
 __do_sys_writev fs/read_write.c:1131 [inline]
 __se_sys_writev fs/read_write.c:1128 [inline]
 __x64_sys_writev+0x75/0xb0 fs/read_write.c:1128
 do_syscall_64+0x103/0x670 arch/x86/entry/common.c:298
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: d58e468b1112 ("flow_dissector: implements flow dissector BPF hook")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Cc: Petar Penkov 
Cc: Stanislav Fomichev 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

fib_rules: return 0 directly if an exactly same rule exists when NLM_F_EXCL not supplied

2019-05-16T17:35:36+00:00

[ Upstream commit e9919a24d3022f72bcadc407e73a6ef17093a849 ]

With commit 153380ec4b9 ("fib_rules: Added NLM_F_EXCL support to
fib_nl_newrule") we now able to check if a rule already exists. But this
only works with iproute2. For other tools like libnl, NetworkManager,
it still could add duplicate rules with only NLM_F_CREATE flag, like

[localhost ~ ]# ip rule
0:      from all lookup local
32766:  from all lookup main
32767:  from all lookup default
100000: from 192.168.7.5 lookup 5
100000: from 192.168.7.5 lookup 5

As it doesn't make sense to create two duplicate rules, let's just return
0 if the rule exists.

Fixes: 153380ec4b9 ("fib_rules: Added NLM_F_EXCL support to fib_nl_newrule")
Reported-by: Thomas Haller 
Signed-off-by: Hangbin Liu 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

socket: fix compat SO_RCVTIMEO_NEW/SO_SNDTIMEO_NEW

2019-04-17T04:52:22+00:00

It looks like the new socket options only work correctly
for native execution, but in case of compat mode fall back
to the old behavior as we ignore the 'old_timeval' flag.

Rework so we treat SO_RCVTIMEO_NEW/SO_SNDTIMEO_NEW the
same way in compat and native 32-bit mode.

Cc: Deepa Dinamani 
Fixes: a9beb86ae6e5 ("sock: Add SO_RCVTIMEO_NEW and SO_SNDTIMEO_NEW")
Signed-off-by: Arnd Bergmann 
Acked-by: Deepa Dinamani 
Signed-off-by: David S. Miller

net: Fix missing meta data in skb with vlan packet

2019-04-17T04:29:38+00:00

skb_reorder_vlan_header() should move XDP meta data with ethernet header
if XDP meta data exists.

Fixes: de8f3a83b0a0 ("bpf: add meta pointer for direct access")
Signed-off-by: Yuya Kusakabe 
Signed-off-by: Takeru Hayasaka 
Co-developed-by: Takeru Hayasaka 
Reviewed-by: Toshiaki Makita 
Signed-off-by: David S. Miller

net/core: work around section mismatch warning for ptp_classifier

2019-04-17T03:46:17+00:00

The routine ptp_classifier_init() uses an initializer for an
automatic struct type variable which refers to an __initdata
symbol. This is perfectly legal, but may trigger a section
mismatch warning when running the compiler in -fpic mode, due
to the fact that the initializer may be emitted into an anonymous
.data section thats lack the __init annotation. So work around it
by using assignments instead.

Signed-off-by: Ard Biesheuvel 
Signed-off-by: Gerald Schaefer 
Signed-off-by: David S. Miller

Revert "net-sysfs: Fix memory leak in netdev_register_kobject"

2019-04-15T20:10:27+00:00

This reverts commit 6b70fc94afd165342876e53fc4b2f7d085009945.

The reverted bugfix will cause another issue.
Reported by syzbot+6024817a931b2830bc93@syzkaller.appspotmail.com.
See https://syzkaller.appspot.com/x/log.txt?x=1737671b200000 for
details.

Signed-off-by: Wang Hai 
Acked-by: Andy Shevchenko 
Signed-off-by: David S. Miller

rtnetlink: fix rtnl_valid_stats_req() nlmsg_len check

2019-04-14T21:10:08+00:00

Jakub forgot to either use nlmsg_len() or nlmsg_msg_size(),
allowing KMSAN to detect a possible uninit-value in rtnl_stats_get

BUG: KMSAN: uninit-value in rtnl_stats_get+0x6d9/0x11d0 net/core/rtnetlink.c:4997
CPU: 0 PID: 10428 Comm: syz-executor034 Not tainted 5.1.0-rc2+ #24
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+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x131/0x2a0 mm/kmsan/kmsan.c:619
 __msan_warning+0x7a/0xf0 mm/kmsan/kmsan_instr.c:310
 rtnl_stats_get+0x6d9/0x11d0 net/core/rtnetlink.c:4997
 rtnetlink_rcv_msg+0x115b/0x1550 net/core/rtnetlink.c:5192
 netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2485
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5210
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x127f/0x1300 net/netlink/af_netlink.c:1925
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg net/socket.c:632 [inline]
 ___sys_sendmsg+0xdb3/0x1220 net/socket.c:2137
 __sys_sendmsg net/socket.c:2175 [inline]
 __do_sys_sendmsg net/socket.c:2184 [inline]
 __se_sys_sendmsg+0x305/0x460 net/socket.c:2182
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2182
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Fixes: 51bc860d4a99 ("rtnetlink: stats: validate attributes in get as well as dumps")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Cc: Jakub Kicinski 
Signed-off-by: David S. Miller

bpf: Check address length before reading address family

2019-04-12T17:25:03+00:00

KMSAN will complain if valid address length passed to bpf_bind() is
shorter than sizeof("struct sockaddr"->sa_family) bytes.

Signed-off-by: Tetsuo Handa 
Acked-by: Andrey Ignatov 
Signed-off-by: David S. Miller

failover: allow name change on IFF_UP slave interfaces

2019-04-11T05:12:26+00:00

When a netdev appears through hot plug then gets enslaved by a failover
master that is already up and running, the slave will be opened
right away after getting enslaved. Today there's a race that userspace
(udev) may fail to rename the slave if the kernel (net_failover)
opens the slave earlier than when the userspace rename happens.
Unlike bond or team, the primary slave of failover can't be renamed by
userspace ahead of time, since the kernel initiated auto-enslavement is
unable to, or rather, is never meant to be synchronized with the rename
request from userspace.

As the failover slave interfaces are not designed to be operated
directly by userspace apps: IP configuration, filter rules with
regard to network traffic passing and etc., should all be done on master
interface. In general, userspace apps only care about the
name of master interface, while slave names are less important as long
as admin users can see reliable names that may carry
other information describing the netdev. For e.g., they can infer that
"ens3nsby" is a standby slave of "ens3", while for a
name like "eth0" they can't tell which master it belongs to.

Historically the name of IFF_UP interface can't be changed because
there might be admin script or management software that is already
relying on such behavior and assumes that the slave name can't be
changed once UP. But failover is special: with the in-kernel
auto-enslavement mechanism, the userspace expectation for device
enumeration and bring-up order is already broken. Previously initramfs
and various userspace config tools were modified to bypass failover
slaves because of auto-enslavement and duplicate MAC address. Similarly,
in case that users care about seeing reliable slave name, the new type
of failover slaves needs to be taken care of specifically in userspace
anyway.

It's less risky to lift up the rename restriction on failover slave
which is already UP. Although it's possible this change may potentially
break userspace component (most likely configuration scripts or
management software) that assumes slave name can't be changed while
UP, it's relatively a limited and controllable set among all userspace
components, which can be fixed specifically to listen for the rename
events on failover slaves. Userspace component interacting with slaves
is expected to be changed to operate on failover master interface
instead, as the failover slave is dynamic in nature which may come and
go at any point.  The goal is to make the role of failover slaves less
relevant, and userspace components should only deal with failover master
in the long run.

Fixes: 30c8bd5aa8b2 ("net: Introduce generic failover module")
Signed-off-by: Si-Wei Liu 
Reviewed-by: Liran Alon 
Acked-by: Sridhar Samudrala 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

2019-04-04T20:30:55+00:00

Daniel Borkmann says:

====================
pull-request: bpf 2019-04-04

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Batch of fixes to the existing BPF flow dissector API to support
   calling BPF programs from the eth_get_headlen context (support for
   latter is planned to be added in bpf-next), from Stanislav.
====================

Signed-off-by: David S. Miller