linux-stable.git/net, branch v5.9.3

net: protect tcf_block_unbind with block lock

2020-11-01T11:47:07+00:00

[ Upstream commit d6535dca28859d8d9ef80894eb287b2ac35a32e8 ]

The tcf_block_unbind() expects that the caller will take block->cb_lock
before calling it, however the code took RTNL lock and dropped cb_lock
instead. This causes to the following kernel panic.

 WARNING: CPU: 1 PID: 13524 at net/sched/cls_api.c:1488 tcf_block_unbind+0x2db/0x420
 Modules linked in: mlx5_ib mlx5_core mlxfw ptp pps_core act_mirred act_tunnel_key cls_flower vxlan ip6_udp_tunnel udp_tunnel dummy sch_ingress openvswitch nsh xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink xt_addrtype iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 br_netfilter rpcrdma rdma_ucm ib_iser libiscsi scsi_transport_iscsi ib_umad ib_ipoib rdma_cm iw_cm ib_cm ib_uverbs ib_core overlay [last unloaded: mlxfw]
 CPU: 1 PID: 13524 Comm: test-ecmp-add-v Tainted: G        W         5.9.0+ #1
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
 RIP: 0010:tcf_block_unbind+0x2db/0x420
 Code: ff 48 83 c4 40 5b 5d 41 5c 41 5d 41 5e 41 5f c3 49 8d bc 24 30 01 00 00 be ff ff ff ff e8 7d 7f 70 00 85 c0 0f 85 7b fd ff ff <0f> 0b e9 74 fd ff ff 48 c7 c7 dc 6a 24 84 e8 02 ec fe fe e9 55 fd
 RSP: 0018:ffff888117d17968 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: ffff88812f713c00 RCX: 1ffffffff0848d5b
 RDX: 0000000000000001 RSI: ffff88814fbc8130 RDI: ffff888107f2b878
 RBP: 1ffff11022fa2f3f R08: 0000000000000000 R09: ffffffff84115a87
 R10: fffffbfff0822b50 R11: ffff888107f2b898 R12: ffff88814fbc8000
 R13: ffff88812f713c10 R14: ffff888117d17a38 R15: ffff88814fbc80c0
 FS:  00007f6593d36740(0000) GS:ffff8882a4f00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00005607a00758f8 CR3: 0000000131aea006 CR4: 0000000000170ea0
 Call Trace:
  tc_block_indr_cleanup+0x3e0/0x5a0
  ? tcf_block_unbind+0x420/0x420
  ? __mutex_unlock_slowpath+0xe7/0x610
  flow_indr_dev_unregister+0x5e2/0x930
  ? mlx5e_restore_tunnel+0xdf0/0xdf0 [mlx5_core]
  ? mlx5e_restore_tunnel+0xdf0/0xdf0 [mlx5_core]
  ? flow_indr_block_cb_alloc+0x3c0/0x3c0
  ? mlx5_db_free+0x37c/0x4b0 [mlx5_core]
  mlx5e_cleanup_rep_tx+0x8b/0xc0 [mlx5_core]
  mlx5e_detach_netdev+0xe5/0x120 [mlx5_core]
  mlx5e_vport_rep_unload+0x155/0x260 [mlx5_core]
  esw_offloads_disable+0x227/0x2b0 [mlx5_core]
  mlx5_eswitch_disable_locked.cold+0x38e/0x699 [mlx5_core]
  mlx5_eswitch_disable+0x94/0xf0 [mlx5_core]
  mlx5_device_disable_sriov+0x183/0x1f0 [mlx5_core]
  mlx5_core_sriov_configure+0xfd/0x230 [mlx5_core]
  sriov_numvfs_store+0x261/0x2f0
  ? sriov_drivers_autoprobe_store+0x110/0x110
  ? sysfs_file_ops+0x170/0x170
  ? sysfs_file_ops+0x117/0x170
  ? sysfs_file_ops+0x170/0x170
  kernfs_fop_write+0x1ff/0x3f0
  ? rcu_read_lock_any_held+0x6e/0x90
  vfs_write+0x1f3/0x620
  ksys_write+0xf9/0x1d0
  ? __x64_sys_read+0xb0/0xb0
  ? lockdep_hardirqs_on_prepare+0x273/0x3f0
  ? syscall_enter_from_user_mode+0x1d/0x50
  do_syscall_64+0x2d/0x40
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

<...>

 ---[ end trace bfdd028ada702879 ]---

Fixes: 0fdcf78d5973 ("net: use flow_indr_dev_setup_offload()")
Signed-off-by: Leon Romanovsky 
Link: https://lore.kernel.org/r/20201026123327.1141066-1-leon@kernel.org
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

net/smc: fix suppressed return code

2020-11-01T11:47:07+00:00

[ Upstream commit 96d6fded958d971a3695009e0ed43aca6c598283 ]

The patch that repaired the invalid return code in smcd_new_buf_create()
missed to take care of errno ENOSPC which has a special meaning that no
more DMBEs can be registered on the device. Fix that by keeping this
errno value during the translation of the return code.

Fixes: 6b1bbf94ab36 ("net/smc: fix invalid return code in smcd_new_buf_create()")
Signed-off-by: Karsten Graul 
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

net/smc: fix invalid return code in smcd_new_buf_create()

2020-11-01T11:47:06+00:00

[ Upstream commit 6b1bbf94ab369d97ed3bdaa561521a52c27ef619 ]

smc_ism_register_dmb() returns error codes set by the ISM driver which
are not guaranteed to be negative or in the errno range. Such values
would not be handled by ERR_PTR() and finally the return code will be
used as a memory address.
Fix that by using a valid negative errno value with ERR_PTR().

Fixes: 72b7f6c48708 ("net/smc: unique reason code for exceeded max dmb count")
Signed-off-by: Karsten Graul 
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

tipc: fix memory leak caused by tipc_buf_append()

2020-11-01T11:47:06+00:00

[ Upstream commit ceb1eb2fb609c88363e06618b8d4bbf7815a4e03 ]

Commit ed42989eab57 ("tipc: fix the skb_unshare() in tipc_buf_append()")
replaced skb_unshare() with skb_copy() to not reduce the data reference
counter of the original skb intentionally. This is not the correct
way to handle the cloned skb because it causes memory leak in 2
following cases:
 1/ Sending multicast messages via broadcast link
  The original skb list is cloned to the local skb list for local
  destination. After that, the data reference counter of each skb
  in the original list has the value of 2. This causes each skb not
  to be freed after receiving ACK:
  tipc_link_advance_transmq()
  {
   ...
   /* release skb */
   __skb_unlink(skb, &l->transmq);
   kfree_skb(skb); <-- memory exists after being freed
  }

 2/ Sending multicast messages via replicast link
  Similar to the above case, each skb cannot be freed after purging
  the skb list:
  tipc_mcast_xmit()
  {
   ...
   __skb_queue_purge(pkts); <-- memory exists after being freed
  }

This commit fixes this issue by using skb_unshare() instead. Besides,
to avoid use-after-free error reported by KASAN, the pointer to the
fragment is set to NULL before calling skb_unshare() to make sure that
the original skb is not freed after freeing the fragment 2 times in
case skb_unshare() returns NULL.

Fixes: ed42989eab57 ("tipc: fix the skb_unshare() in tipc_buf_append()")
Acked-by: Jon Maloy 
Reported-by: Thang Hoang Ngo 
Signed-off-by: Tung Nguyen 
Reviewed-by: Xin Long 
Acked-by: Cong Wang 
Link: https://lore.kernel.org/r/20201027032403.1823-1-tung.q.nguyen@dektech.com.au
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

tcp: Prevent low rmem stalls with SO_RCVLOWAT.

2020-11-01T11:47:06+00:00

[ Upstream commit 435ccfa894e35e3d4a1799e6ac030e48a7b69ef5 ]

With SO_RCVLOWAT, under memory pressure,
it is possible to enter a state where:

1. We have not received enough bytes to satisfy SO_RCVLOWAT.
2. We have not entered buffer pressure (see tcp_rmem_pressure()).
3. But, we do not have enough buffer space to accept more packets.

In this case, we advertise 0 rwnd (due to #3) but the application does
not drain the receive queue (no wakeup because of #1 and #2) so the
flow stalls.

Modify the heuristic for SO_RCVLOWAT so that, if we are advertising
rwnd<=rcv_mss, force a wakeup to prevent a stall.

Without this patch, setting tcp_rmem to 6143 and disabling TCP
autotune causes a stalled flow. With this patch, no stall occurs. This
is with RPC-style traffic with large messages.

Fixes: 03f45c883c6f ("tcp: avoid extra wakeups for SO_RCVLOWAT users")
Signed-off-by: Arjun Roy 
Acked-by: Soheil Hassas Yeganeh 
Acked-by: Neal Cardwell 
Signed-off-by: Eric Dumazet 
Link: https://lore.kernel.org/r/20201023184709.217614-1-arjunroy.kdev@gmail.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

net/sched: act_mpls: Add softdep on mpls_gso.ko

2020-11-01T11:47:06+00:00

TCA_MPLS_ACT_PUSH and TCA_MPLS_ACT_MAC_PUSH might be used on gso
packets. Such packets will thus require mpls_gso.ko for segmentation.

v2: Drop dependency on CONFIG_NET_MPLS_GSO in Kconfig (from Jakub and
    David).

Fixes: 2a2ea50870ba ("net: sched: add mpls manipulation actions to TC")
Signed-off-by: Guillaume Nault 
Link: https://lore.kernel.org/r/1f6cab15bbd15666795061c55563aaf6a386e90e.1603708007.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

netem: fix zero division in tabledist

2020-11-01T11:47:05+00:00

[ Upstream commit eadd1befdd778a1eca57fad058782bd22b4db804 ]

Currently it is possible to craft a special netlink RTM_NEWQDISC
command that can result in jitter being equal to 0x80000000. It is
enough to set the 32 bit jitter to 0x02000000 (it will later be
multiplied by 2^6) or just set the 64 bit jitter via
TCA_NETEM_JITTER64. This causes an overflow during the generation of
uniformly distributed numbers in tabledist(), which in turn leads to
division by zero (sigma != 0, but sigma * 2 is 0).

The related fragment of code needs 32-bit division - see commit
9b0ed89 ("netem: remove unnecessary 64 bit modulus"), so switching to
64 bit is not an option.

Fix the issue by keeping the value of jitter within the range that can
be adequately handled by tabledist() - [0;INT_MAX]. As negative std
deviation makes no sense, take the absolute value of the passed value
and cap it at INT_MAX. Inside tabledist(), switch to unsigned 32 bit
arithmetic in order to prevent overflows.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Aleksandr Nogikh 
Reported-by: syzbot+ec762a6342ad0d3c0d8f@syzkaller.appspotmail.com
Acked-by: Stephen Hemminger 
Link: https://lore.kernel.org/r/20201028170731.1383332-1-aleksandrnogikh@gmail.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

netfilter: nftables_offload: KASAN slab-out-of-bounds Read in nft_flow_rule_create

2020-11-01T11:47:00+00:00

commit 31cc578ae2de19c748af06d859019dced68e325d upstream.

This patch fixes the issue due to:

BUG: KASAN: slab-out-of-bounds in nft_flow_rule_create+0x622/0x6a2
net/netfilter/nf_tables_offload.c:40
Read of size 8 at addr ffff888103910b58 by task syz-executor227/16244

The error happens when expr->ops is accessed early on before performing the boundary check and after nft_expr_next() moves the expr to go out-of-bounds.

This patch checks the boundary condition before expr->ops that fixes the slab-out-of-bounds Read issue.

Add nft_expr_more() and use it to fix this problem.

Signed-off-by: Saeed Mirzamohammadi 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

ipvs: Fix uninit-value in do_ip_vs_set_ctl()

2020-10-29T09:12:19+00:00

[ Upstream commit c5a8a8498eed1c164afc94f50a939c1a10abf8ad ]

do_ip_vs_set_ctl() is referencing uninitialized stack value when `len` is
zero. Fix it.

Reported-by: syzbot+23b5f9e7caf61d9a3898@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?id=46ebfb92a8a812621a001ef04d90dfa459520fe2
Suggested-by: Julian Anastasov 
Signed-off-by: Peilin Ye 
Acked-by: Julian Anastasov 
Reviewed-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

Bluetooth: Only mark socket zapped after unlocking

2020-10-29T09:12:16+00:00

[ Upstream commit 20ae4089d0afeb24e9ceb026b996bfa55c983cc2 ]

Since l2cap_sock_teardown_cb doesn't acquire the channel lock before
setting the socket as zapped, it could potentially race with
l2cap_sock_release which frees the socket. Thus, wait until the cleanup
is complete before marking the socket as zapped.

This race was reproduced on a JBL GO speaker after the remote device
rejected L2CAP connection due to resource unavailability.

Here is a dmesg log with debug logs from a repro of this bug:
[ 3465.424086] Bluetooth: hci_core.c:hci_acldata_packet() hci0 len 16 handle 0x0003 flags 0x0002
[ 3465.424090] Bluetooth: hci_conn.c:hci_conn_enter_active_mode() hcon 00000000cfedd07d mode 0
[ 3465.424094] Bluetooth: l2cap_core.c:l2cap_recv_acldata() conn 000000007eae8952 len 16 flags 0x2
[ 3465.424098] Bluetooth: l2cap_core.c:l2cap_recv_frame() len 12, cid 0x0001
[ 3465.424102] Bluetooth: l2cap_core.c:l2cap_raw_recv() conn 000000007eae8952
[ 3465.424175] Bluetooth: l2cap_core.c:l2cap_sig_channel() code 0x03 len 8 id 0x0c
[ 3465.424180] Bluetooth: l2cap_core.c:l2cap_connect_create_rsp() dcid 0x0045 scid 0x0000 result 0x02 status 0x00
[ 3465.424189] Bluetooth: l2cap_core.c:l2cap_chan_put() chan 000000006acf9bff orig refcnt 4
[ 3465.424196] Bluetooth: l2cap_core.c:l2cap_chan_del() chan 000000006acf9bff, conn 000000007eae8952, err 111, state BT_CONNECT
[ 3465.424203] Bluetooth: l2cap_sock.c:l2cap_sock_teardown_cb() chan 000000006acf9bff state BT_CONNECT
[ 3465.424221] Bluetooth: l2cap_core.c:l2cap_chan_put() chan 000000006acf9bff orig refcnt 3
[ 3465.424226] Bluetooth: hci_core.h:hci_conn_drop() hcon 00000000cfedd07d orig refcnt 6
[ 3465.424234] BUG: spinlock bad magic on CPU#2, kworker/u17:0/159
[ 3465.425626] Bluetooth: hci_sock.c:hci_sock_sendmsg() sock 000000002bb0cb64 sk 00000000a7964053
[ 3465.430330]  lock: 0xffffff804410aac0, .magic: 00000000, .owner: /-1, .owner_cpu: 0
[ 3465.430332] Causing a watchdog bite!

Signed-off-by: Abhishek Pandit-Subedi 
Reported-by: Balakrishna Godavarthi 
Reviewed-by: Manish Mandlik 
Signed-off-by: Marcel Holtmann 
Signed-off-by: Sasha Levin