<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/include/net, branch v5.4.113</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v5.4.113</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v5.4.113'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2021-04-14T06:24:14+00:00</updated>
<entry>
<title>sch_red: fix off-by-one checks in red_check_params()</title>
<updated>2021-04-14T06:24:14+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2021-03-25T18:14:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=840a181729ac06da74fbb34ff043c2f4015d4ea5'/>
<id>urn:sha1:840a181729ac06da74fbb34ff043c2f4015d4ea5</id>
<content type='text'>
[ Upstream commit 3a87571f0ffc51ba3bf3ecdb6032861d0154b164 ]

This fixes following syzbot report:

UBSAN: shift-out-of-bounds in ./include/net/red.h:237:23
shift exponent 32 is too large for 32-bit type 'unsigned int'
CPU: 1 PID: 8418 Comm: syz-executor170 Not tainted 5.12.0-rc4-next-20210324-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x141/0x1d7 lib/dump_stack.c:120
 ubsan_epilogue+0xb/0x5a lib/ubsan.c:148
 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x181 lib/ubsan.c:327
 red_set_parms include/net/red.h:237 [inline]
 choke_change.cold+0x3c/0xc8 net/sched/sch_choke.c:414
 qdisc_create+0x475/0x12f0 net/sched/sch_api.c:1247
 tc_modify_qdisc+0x4c8/0x1a50 net/sched/sch_api.c:1663
 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5553
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2502
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:674
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2350
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2404
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2433
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x43f039
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 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 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdfa725168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043f039
RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000004
RBP: 0000000000403020 R08: 0000000000400488 R09: 0000000000400488
R10: 0000000000400488 R11: 0000000000000246 R12: 00000000004030b0
R13: 0000000000000000 R14: 00000000004ac018 R15: 0000000000400488

Fixes: 8afa10cbe281 ("net_sched: red: Avoid illegal values")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>xfrm: Fix NULL pointer dereference on policy lookup</title>
<updated>2021-04-14T06:24:14+00:00</updated>
<author>
<name>Steffen Klassert</name>
<email>steffen.klassert@secunet.com</email>
</author>
<published>2021-03-23T08:26:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=f819977ad42caf824b236fc919786c672d040ee8'/>
<id>urn:sha1:f819977ad42caf824b236fc919786c672d040ee8</id>
<content type='text'>
[ Upstream commit b1e3a5607034aa0a481c6f69a6893049406665fb ]

When xfrm interfaces are used in combination with namespaces
and ESP offload, we get a dst_entry NULL pointer dereference.
This is because we don't have a dst_entry attached in the ESP
offloading case and we need to do a policy lookup before the
namespace transition.

Fix this by expicit checking of skb_dst(skb) before accessing it.

Fixes: f203b76d78092 ("xfrm: Add virtual xfrm interfaces")
Signed-off-by: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: xfrm: Localize sequence counter per network namespace</title>
<updated>2021-04-14T06:24:13+00:00</updated>
<author>
<name>Ahmed S. Darwish</name>
<email>a.darwish@linutronix.de</email>
</author>
<published>2021-03-16T10:56:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=a128e07b472ba254dc98e85b6c718802343e7e19'/>
<id>urn:sha1:a128e07b472ba254dc98e85b6c718802343e7e19</id>
<content type='text'>
[ Upstream commit e88add19f68191448427a6e4eb059664650a837f ]

A sequence counter write section must be serialized or its internal
state can get corrupted. The "xfrm_state_hash_generation" seqcount is
global, but its write serialization lock (net-&gt;xfrm.xfrm_state_lock) is
instantiated per network namespace. The write protection is thus
insufficient.

To provide full protection, localize the sequence counter per network
namespace instead. This should be safe as both the seqcount read and
write sections access data exclusively within the network namespace. It
also lays the foundation for transforming "xfrm_state_hash_generation"
data type from seqcount_t to seqcount_LOCKNAME_t in further commits.

Fixes: b65e3d7be06f ("xfrm: state: add sequence count to detect hash resizes")
Signed-off-by: Ahmed S. Darwish &lt;a.darwish@linutronix.de&gt;
Signed-off-by: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: let skb_orphan_partial wake-up waiters.</title>
<updated>2021-04-14T06:24:12+00:00</updated>
<author>
<name>Paolo Abeni</name>
<email>pabeni@redhat.com</email>
</author>
<published>2021-03-30T16:43:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=b02bded94b91ca27888d9663e690e1c968d06c45'/>
<id>urn:sha1:b02bded94b91ca27888d9663e690e1c968d06c45</id>
<content type='text'>
commit 9adc89af724f12a03b47099cd943ed54e877cd59 upstream.

Currently the mentioned helper can end-up freeing the socket wmem
without waking-up any processes waiting for more write memory.

If the partially orphaned skb is attached to an UDP (or raw) socket,
the lack of wake-up can hang the user-space.

Even for TCP sockets not calling the sk destructor could have bad
effects on TSQ.

Address the issue using skb_orphan to release the sk wmem before
setting the new sock_efree destructor. Additionally bundle the
whole ownership update in a new helper, so that later other
potential users could avoid duplicate code.

v1 -&gt; v2:
 - use skb_orphan() instead of sort of open coding it (Eric)
 - provide an helper for the ownership change (Eric)

Fixes: f6ba8d33cfbb ("netem: fix skb_orphan_partial()")
Suggested-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>can: dev: Move device back to init netns on owning netns delete</title>
<updated>2021-03-30T12:35:29+00:00</updated>
<author>
<name>Martin Willi</name>
<email>martin@strongswan.org</email>
</author>
<published>2021-03-02T12:24:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=f866d1fa48e40af651d9c78b7f3c5a9a6ccf1815'/>
<id>urn:sha1:f866d1fa48e40af651d9c78b7f3c5a9a6ccf1815</id>
<content type='text'>
commit 3a5ca857079ea022e0b1b17fc154f7ad7dbc150f upstream.

When a non-initial netns is destroyed, the usual policy is to delete
all virtual network interfaces contained, but move physical interfaces
back to the initial netns. This keeps the physical interface visible
on the system.

CAN devices are somewhat special, as they define rtnl_link_ops even
if they are physical devices. If a CAN interface is moved into a
non-initial netns, destroying that netns lets the interface vanish
instead of moving it back to the initial netns. default_device_exit()
skips CAN interfaces due to having rtnl_link_ops set. Reproducer:

  ip netns add foo
  ip link set can0 netns foo
  ip netns delete foo

WARNING: CPU: 1 PID: 84 at net/core/dev.c:11030 ops_exit_list+0x38/0x60
CPU: 1 PID: 84 Comm: kworker/u4:2 Not tainted 5.10.19 #1
Workqueue: netns cleanup_net
[&lt;c010e700&gt;] (unwind_backtrace) from [&lt;c010a1d8&gt;] (show_stack+0x10/0x14)
[&lt;c010a1d8&gt;] (show_stack) from [&lt;c086dc10&gt;] (dump_stack+0x94/0xa8)
[&lt;c086dc10&gt;] (dump_stack) from [&lt;c086b938&gt;] (__warn+0xb8/0x114)
[&lt;c086b938&gt;] (__warn) from [&lt;c086ba10&gt;] (warn_slowpath_fmt+0x7c/0xac)
[&lt;c086ba10&gt;] (warn_slowpath_fmt) from [&lt;c0629f20&gt;] (ops_exit_list+0x38/0x60)
[&lt;c0629f20&gt;] (ops_exit_list) from [&lt;c062a5c4&gt;] (cleanup_net+0x230/0x380)
[&lt;c062a5c4&gt;] (cleanup_net) from [&lt;c0142c20&gt;] (process_one_work+0x1d8/0x438)
[&lt;c0142c20&gt;] (process_one_work) from [&lt;c0142ee4&gt;] (worker_thread+0x64/0x5a8)
[&lt;c0142ee4&gt;] (worker_thread) from [&lt;c0148a98&gt;] (kthread+0x148/0x14c)
[&lt;c0148a98&gt;] (kthread) from [&lt;c0100148&gt;] (ret_from_fork+0x14/0x2c)

To properly restore physical CAN devices to the initial netns on owning
netns exit, introduce a flag on rtnl_link_ops that can be set by drivers.
For CAN devices setting this flag, default_device_exit() considers them
non-virtual, applying the usual namespace move.

The issue was introduced in the commit mentioned below, as at that time
CAN devices did not have a dellink() operation.

Fixes: e008b5fc8dc7 ("net: Simplfy default_device_exit and improve batching.")
Link: https://lore.kernel.org/r/20210302122423.872326-1-martin@strongswan.org
Signed-off-by: Martin Willi &lt;martin@strongswan.org&gt;
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>tcp: relookup sock for RST+ACK packets handled by obsolete req sock</title>
<updated>2021-03-30T12:35:26+00:00</updated>
<author>
<name>Alexander Ovechkin</name>
<email>ovov@yandex-team.ru</email>
</author>
<published>2021-03-15T11:05:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=0a8046daba17190997e598cf6055fef7dd1b6041'/>
<id>urn:sha1:0a8046daba17190997e598cf6055fef7dd1b6041</id>
<content type='text'>
[ Upstream commit 7233da86697efef41288f8b713c10c2499cffe85 ]

Currently tcp_check_req can be called with obsolete req socket for which big
socket have been already created (because of CPU race or early demux
assigning req socket to multiple packets in gro batch).

Commit e0f9759f530bf789e984 ("tcp: try to keep packet if SYN_RCV race
is lost") added retry in case when tcp_check_req is called for PSH|ACK packet.
But if client sends RST+ACK immediatly after connection being
established (it is performing healthcheck, for example) retry does not
occur. In that case tcp_check_req tries to close req socket,
leaving big socket active.

Fixes: e0f9759f530 ("tcp: try to keep packet if SYN_RCV race is lost")
Signed-off-by: Alexander Ovechkin &lt;ovov@yandex-team.ru&gt;
Reported-by: Oleg Senin &lt;olegsenin@yandex-team.ru&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: sched: validate stab values</title>
<updated>2021-03-30T12:35:25+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2021-03-10T16:26:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=267b79a11046110590ccc360c851fb57ffd34b6c'/>
<id>urn:sha1:267b79a11046110590ccc360c851fb57ffd34b6c</id>
<content type='text'>
[ Upstream commit e323d865b36134e8c5c82c834df89109a5c60dab ]

iproute2 package is well behaved, but malicious user space can
provide illegal shift values and trigger UBSAN reports.

Add stab parameter to red_check_params() to validate user input.

syzbot reported:

UBSAN: shift-out-of-bounds in ./include/net/red.h:312:18
shift exponent 111 is too large for 64-bit type 'long unsigned int'
CPU: 1 PID: 14662 Comm: syz-executor.3 Not tainted 5.12.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x141/0x1d7 lib/dump_stack.c:120
 ubsan_epilogue+0xb/0x5a lib/ubsan.c:148
 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x181 lib/ubsan.c:327
 red_calc_qavg_from_idle_time include/net/red.h:312 [inline]
 red_calc_qavg include/net/red.h:353 [inline]
 choke_enqueue.cold+0x18/0x3dd net/sched/sch_choke.c:221
 __dev_xmit_skb net/core/dev.c:3837 [inline]
 __dev_queue_xmit+0x1943/0x2e00 net/core/dev.c:4150
 neigh_hh_output include/net/neighbour.h:499 [inline]
 neigh_output include/net/neighbour.h:508 [inline]
 ip6_finish_output2+0x911/0x1700 net/ipv6/ip6_output.c:117
 __ip6_finish_output net/ipv6/ip6_output.c:182 [inline]
 __ip6_finish_output+0x4c1/0xe10 net/ipv6/ip6_output.c:161
 ip6_finish_output+0x35/0x200 net/ipv6/ip6_output.c:192
 NF_HOOK_COND include/linux/netfilter.h:290 [inline]
 ip6_output+0x1e4/0x530 net/ipv6/ip6_output.c:215
 dst_output include/net/dst.h:448 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 NF_HOOK include/linux/netfilter.h:295 [inline]
 ip6_xmit+0x127e/0x1eb0 net/ipv6/ip6_output.c:320
 inet6_csk_xmit+0x358/0x630 net/ipv6/inet6_connection_sock.c:135
 dccp_transmit_skb+0x973/0x12c0 net/dccp/output.c:138
 dccp_send_reset+0x21b/0x2b0 net/dccp/output.c:535
 dccp_finish_passive_close net/dccp/proto.c:123 [inline]
 dccp_finish_passive_close+0xed/0x140 net/dccp/proto.c:118
 dccp_terminate_connection net/dccp/proto.c:958 [inline]
 dccp_close+0xb3c/0xe60 net/dccp/proto.c:1028
 inet_release+0x12e/0x280 net/ipv4/af_inet.c:431
 inet6_release+0x4c/0x70 net/ipv6/af_inet6.c:478
 __sock_release+0xcd/0x280 net/socket.c:599
 sock_close+0x18/0x20 net/socket.c:1258
 __fput+0x288/0x920 fs/file_table.c:280
 task_work_run+0xdd/0x1a0 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]

Fixes: 8afa10cbe281 ("net_sched: red: Avoid illegal values")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>ipv6: fix suspecious RCU usage warning</title>
<updated>2021-03-30T12:35:25+00:00</updated>
<author>
<name>Wei Wang</name>
<email>weiwan@google.com</email>
</author>
<published>2021-03-10T02:20:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=c6b6c7a92fe594b107ab9ec26efa0585d1dbcee6'/>
<id>urn:sha1:c6b6c7a92fe594b107ab9ec26efa0585d1dbcee6</id>
<content type='text'>
[ Upstream commit 28259bac7f1dde06d8ba324e222bbec9d4e92f2b ]

Syzbot reported the suspecious RCU usage in nexthop_fib6_nh() when
called from ipv6_route_seq_show(). The reason is ipv6_route_seq_start()
calls rcu_read_lock_bh(), while nexthop_fib6_nh() calls
rcu_dereference_rtnl().
The fix proposed is to add a variant of nexthop_fib6_nh() to use
rcu_dereference_bh_rtnl() for ipv6_route_seq_show().

The reported trace is as follows:
./include/net/nexthop.h:416 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
2 locks held by syz-executor.0/17895:
     at: seq_read+0x71/0x12a0 fs/seq_file.c:169
     at: seq_file_net include/linux/seq_file_net.h:19 [inline]
     at: ipv6_route_seq_start+0xaf/0x300 net/ipv6/ip6_fib.c:2616

stack backtrace:
CPU: 1 PID: 17895 Comm: syz-executor.0 Not tainted 4.15.0-syzkaller #0
Call Trace:
 [&lt;ffffffff849edf9e&gt;] __dump_stack lib/dump_stack.c:17 [inline]
 [&lt;ffffffff849edf9e&gt;] dump_stack+0xd8/0x147 lib/dump_stack.c:53
 [&lt;ffffffff8480b7fa&gt;] lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5745
 [&lt;ffffffff8459ada6&gt;] nexthop_fib6_nh include/net/nexthop.h:416 [inline]
 [&lt;ffffffff8459ada6&gt;] ipv6_route_native_seq_show net/ipv6/ip6_fib.c:2488 [inline]
 [&lt;ffffffff8459ada6&gt;] ipv6_route_seq_show+0x436/0x7a0 net/ipv6/ip6_fib.c:2673
 [&lt;ffffffff81c556df&gt;] seq_read+0xccf/0x12a0 fs/seq_file.c:276
 [&lt;ffffffff81dbc62c&gt;] proc_reg_read+0x10c/0x1d0 fs/proc/inode.c:231
 [&lt;ffffffff81bc28ae&gt;] do_loop_readv_writev fs/read_write.c:714 [inline]
 [&lt;ffffffff81bc28ae&gt;] do_loop_readv_writev fs/read_write.c:701 [inline]
 [&lt;ffffffff81bc28ae&gt;] do_iter_read+0x49e/0x660 fs/read_write.c:935
 [&lt;ffffffff81bc81ab&gt;] vfs_readv+0xfb/0x170 fs/read_write.c:997
 [&lt;ffffffff81c88847&gt;] kernel_readv fs/splice.c:361 [inline]
 [&lt;ffffffff81c88847&gt;] default_file_splice_read+0x487/0x9c0 fs/splice.c:416
 [&lt;ffffffff81c86189&gt;] do_splice_to+0x129/0x190 fs/splice.c:879
 [&lt;ffffffff81c86f66&gt;] splice_direct_to_actor+0x256/0x890 fs/splice.c:951
 [&lt;ffffffff81c8777d&gt;] do_splice_direct+0x1dd/0x2b0 fs/splice.c:1060
 [&lt;ffffffff81bc4747&gt;] do_sendfile+0x597/0xce0 fs/read_write.c:1459
 [&lt;ffffffff81bca205&gt;] SYSC_sendfile64 fs/read_write.c:1520 [inline]
 [&lt;ffffffff81bca205&gt;] SyS_sendfile64+0x155/0x170 fs/read_write.c:1506
 [&lt;ffffffff81015fcf&gt;] do_syscall_64+0x1ff/0x310 arch/x86/entry/common.c:305
 [&lt;ffffffff84a00076&gt;] entry_SYSCALL_64_after_hwframe+0x42/0xb7

Fixes: f88d8ea67fbdb ("ipv6: Plumb support for nexthop object in a fib6_info")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Wei Wang &lt;weiwan@google.com&gt;
Cc: David Ahern &lt;dsahern@kernel.org&gt;
Cc: Ido Schimmel &lt;idosch@idosch.org&gt;
Cc: Petr Machata &lt;petrm@nvidia.com&gt;
Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Ido Schimmel &lt;idosch@nvidia.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: sched: fix police ext initialization</title>
<updated>2021-03-04T09:26:53+00:00</updated>
<author>
<name>Vlad Buslov</name>
<email>vladbu@nvidia.com</email>
</author>
<published>2021-02-16T16:22:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=976ee31ea300c827ab713287bbc27e50cd0df053'/>
<id>urn:sha1:976ee31ea300c827ab713287bbc27e50cd0df053</id>
<content type='text'>
commit 396d7f23adf9e8c436dd81a69488b5b6a865acf8 upstream.

When police action is created by cls API tcf_exts_validate() first
conditional that calls tcf_action_init_1() directly, the action idr is not
updated according to latest changes in action API that require caller to
commit newly created action to idr with tcf_idr_insert_many(). This results
such action not being accessible through act API and causes crash reported
by syzbot:

==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: null-ptr-deref in atomic_read include/asm-generic/atomic-instrumented.h:27 [inline]
BUG: KASAN: null-ptr-deref in __tcf_idr_release net/sched/act_api.c:178 [inline]
BUG: KASAN: null-ptr-deref in tcf_idrinfo_destroy+0x129/0x1d0 net/sched/act_api.c:598
Read of size 4 at addr 0000000000000010 by task kworker/u4:5/204

CPU: 0 PID: 204 Comm: kworker/u4:5 Not tainted 5.11.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 __kasan_report mm/kasan/report.c:400 [inline]
 kasan_report.cold+0x5f/0xd5 mm/kasan/report.c:413
 check_memory_region_inline mm/kasan/generic.c:179 [inline]
 check_memory_region+0x13d/0x180 mm/kasan/generic.c:185
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 atomic_read include/asm-generic/atomic-instrumented.h:27 [inline]
 __tcf_idr_release net/sched/act_api.c:178 [inline]
 tcf_idrinfo_destroy+0x129/0x1d0 net/sched/act_api.c:598
 tc_action_net_exit include/net/act_api.h:151 [inline]
 police_exit_net+0x168/0x360 net/sched/act_police.c:390
 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:190
 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:604
 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 204 Comm: kworker/u4:5 Tainted: G    B             5.11.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 panic+0x306/0x73d kernel/panic.c:231
 end_report+0x58/0x5e mm/kasan/report.c:100
 __kasan_report mm/kasan/report.c:403 [inline]
 kasan_report.cold+0x67/0xd5 mm/kasan/report.c:413
 check_memory_region_inline mm/kasan/generic.c:179 [inline]
 check_memory_region+0x13d/0x180 mm/kasan/generic.c:185
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 atomic_read include/asm-generic/atomic-instrumented.h:27 [inline]
 __tcf_idr_release net/sched/act_api.c:178 [inline]
 tcf_idrinfo_destroy+0x129/0x1d0 net/sched/act_api.c:598
 tc_action_net_exit include/net/act_api.h:151 [inline]
 police_exit_net+0x168/0x360 net/sched/act_police.c:390
 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:190
 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:604
 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
Kernel Offset: disabled

Fix the issue by calling tcf_idr_insert_many() after successful action
initialization.

Fixes: 0fedc63fadf0 ("net_sched: commit action insertions together")
Reported-by: syzbot+151e3e714d34ae4ce7e8@syzkaller.appspotmail.com
Signed-off-by: Vlad Buslov &lt;vladbu@nvidia.com&gt;
Reviewed-by: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>net: icmp: pass zeroed opts from icmp{,v6}_ndo_send before sending</title>
<updated>2021-03-04T09:26:53+00:00</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2021-02-23T13:18:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=9875cb3c0968ad37f07d3990eaa10e51a8d1e0b0'/>
<id>urn:sha1:9875cb3c0968ad37f07d3990eaa10e51a8d1e0b0</id>
<content type='text'>
commit ee576c47db60432c37e54b1e2b43a8ca6d3a8dca upstream.

The icmp{,v6}_send functions make all sorts of use of skb-&gt;cb, casting
it with IPCB or IP6CB, assuming the skb to have come directly from the
inet layer. But when the packet comes from the ndo layer, especially
when forwarded, there's no telling what might be in skb-&gt;cb at that
point. As a result, the icmp sending code risks reading bogus memory
contents, which can result in nasty stack overflows such as this one
reported by a user:

    panic+0x108/0x2ea
    __stack_chk_fail+0x14/0x20
    __icmp_send+0x5bd/0x5c0
    icmp_ndo_send+0x148/0x160

In icmp_send, skb-&gt;cb is cast with IPCB and an ip_options struct is read
from it. The optlen parameter there is of particular note, as it can
induce writes beyond bounds. There are quite a few ways that can happen
in __ip_options_echo. For example:

    // sptr/skb are attacker-controlled skb bytes
    sptr = skb_network_header(skb);
    // dptr/dopt points to stack memory allocated by __icmp_send
    dptr = dopt-&gt;__data;
    // sopt is the corrupt skb-&gt;cb in question
    if (sopt-&gt;rr) {
        optlen  = sptr[sopt-&gt;rr+1]; // corrupt skb-&gt;cb + skb-&gt;data
        soffset = sptr[sopt-&gt;rr+2]; // corrupt skb-&gt;cb + skb-&gt;data
	// this now writes potentially attacker-controlled data, over
	// flowing the stack:
        memcpy(dptr, sptr+sopt-&gt;rr, optlen);
    }

In the icmpv6_send case, the story is similar, but not as dire, as only
IP6CB(skb)-&gt;iif and IP6CB(skb)-&gt;dsthao are used. The dsthao case is
worse than the iif case, but it is passed to ipv6_find_tlv, which does
a bit of bounds checking on the value.

This is easy to simulate by doing a `memset(skb-&gt;cb, 0x41,
sizeof(skb-&gt;cb));` before calling icmp{,v6}_ndo_send, and it's only by
good fortune and the rarity of icmp sending from that context that we've
avoided reports like this until now. For example, in KASAN:

    BUG: KASAN: stack-out-of-bounds in __ip_options_echo+0xa0e/0x12b0
    Write of size 38 at addr ffff888006f1f80e by task ping/89
    CPU: 2 PID: 89 Comm: ping Not tainted 5.10.0-rc7-debug+ #5
    Call Trace:
     dump_stack+0x9a/0xcc
     print_address_description.constprop.0+0x1a/0x160
     __kasan_report.cold+0x20/0x38
     kasan_report+0x32/0x40
     check_memory_region+0x145/0x1a0
     memcpy+0x39/0x60
     __ip_options_echo+0xa0e/0x12b0
     __icmp_send+0x744/0x1700

Actually, out of the 4 drivers that do this, only gtp zeroed the cb for
the v4 case, while the rest did not. So this commit actually removes the
gtp-specific zeroing, while putting the code where it belongs in the
shared infrastructure of icmp{,v6}_ndo_send.

This commit fixes the issue by passing an empty IPCB or IP6CB along to
the functions that actually do the work. For the icmp_send, this was
already trivial, thanks to __icmp_send providing the plumbing function.
For icmpv6_send, this required a tiny bit of refactoring to make it
behave like the v4 case, after which it was straight forward.

Fixes: a2b78e9b2cac ("sunvnet: generate ICMP PTMUD messages for smaller port MTUs")
Reported-by: SinYu &lt;liuxyon@gmail.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
Link: https://lore.kernel.org/netdev/CAF=yD-LOF116aHub6RMe8vB8ZpnrrnoTdqhobEx+bvoA8AsP0w@mail.gmail.com/T/
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Link: https://lore.kernel.org/r/20210223131858.72082-1-Jason@zx2c4.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
</feed>
