linux_dsm_epyc7002/net
Jacob Keller 83fe6b8709 sch_fq_codel: zero q->flows_cnt when fq_codel_init fails
When fq_codel_init fails, qdisc_create_dflt will cleanup by using
qdisc_destroy. This function calls the ->reset() op prior to calling the
->destroy() op.

Unfortunately, during the failure flow for sch_fq_codel, the ->flows
parameter is not initialized, so the fq_codel_reset function will null
pointer dereference.

   kernel: BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
   kernel: IP: fq_codel_reset+0x58/0xd0 [sch_fq_codel]
   kernel: PGD 0 P4D 0
   kernel: Oops: 0000 [#1] SMP PTI
   kernel: Modules linked in: i40iw i40e(OE) xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack tun bridge stp llc devlink ebtable_filter ebtables ip6table_filter ip6_tables rpcrdma ib_isert iscsi_target_mod sunrpc ib_iser libiscsi scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm intel_rapl sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel intel_cstate iTCO_wdt iTCO_vendor_support intel_uncore ib_core intel_rapl_perf mei_me mei joydev i2c_i801 lpc_ich ioatdma shpchp wmi sch_fq_codel xfs libcrc32c mgag200 ixgbe drm_kms_helper isci ttm firewire_ohci
   kernel:  mdio drm igb libsas crc32c_intel firewire_core ptp pps_core scsi_transport_sas crc_itu_t dca i2c_algo_bit ipmi_si ipmi_devintf ipmi_msghandler [last unloaded: i40e]
   kernel: CPU: 10 PID: 4219 Comm: ip Tainted: G           OE    4.16.13custom-fq-codel-test+ #3
   kernel: Hardware name: Intel Corporation S2600CO/S2600CO, BIOS SE5C600.86B.02.05.0004.051120151007 05/11/2015
   kernel: RIP: 0010:fq_codel_reset+0x58/0xd0 [sch_fq_codel]
   kernel: RSP: 0018:ffffbfbf4c1fb620 EFLAGS: 00010246
   kernel: RAX: 0000000000000400 RBX: 0000000000000000 RCX: 00000000000005b9
   kernel: RDX: 0000000000000000 RSI: ffff9d03264a60c0 RDI: ffff9cfd17b31c00
   kernel: RBP: 0000000000000001 R08: 00000000000260c0 R09: ffffffffb679c3e9
   kernel: R10: fffff1dab06a0e80 R11: ffff9cfd163af800 R12: ffff9cfd17b31c00
   kernel: R13: 0000000000000001 R14: ffff9cfd153de600 R15: 0000000000000001
   kernel: FS:  00007fdec2f92800(0000) GS:ffff9d0326480000(0000) knlGS:0000000000000000
   kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
   kernel: CR2: 0000000000000008 CR3: 0000000c1956a006 CR4: 00000000000606e0
   kernel: Call Trace:
   kernel:  qdisc_destroy+0x56/0x140
   kernel:  qdisc_create_dflt+0x8b/0xb0
   kernel:  mq_init+0xc1/0xf0
   kernel:  qdisc_create_dflt+0x5a/0xb0
   kernel:  dev_activate+0x205/0x230
   kernel:  __dev_open+0xf5/0x160
   kernel:  __dev_change_flags+0x1a3/0x210
   kernel:  dev_change_flags+0x21/0x60
   kernel:  do_setlink+0x660/0xdf0
   kernel:  ? down_trylock+0x25/0x30
   kernel:  ? xfs_buf_trylock+0x1a/0xd0 [xfs]
   kernel:  ? rtnl_newlink+0x816/0x990
   kernel:  ? _xfs_buf_find+0x327/0x580 [xfs]
   kernel:  ? _cond_resched+0x15/0x30
   kernel:  ? kmem_cache_alloc+0x20/0x1b0
   kernel:  ? rtnetlink_rcv_msg+0x200/0x2f0
   kernel:  ? rtnl_calcit.isra.30+0x100/0x100
   kernel:  ? netlink_rcv_skb+0x4c/0x120
   kernel:  ? netlink_unicast+0x19e/0x260
   kernel:  ? netlink_sendmsg+0x1ff/0x3c0
   kernel:  ? sock_sendmsg+0x36/0x40
   kernel:  ? ___sys_sendmsg+0x295/0x2f0
   kernel:  ? ebitmap_cmp+0x6d/0x90
   kernel:  ? dev_get_by_name_rcu+0x73/0x90
   kernel:  ? skb_dequeue+0x52/0x60
   kernel:  ? __inode_wait_for_writeback+0x7f/0xf0
   kernel:  ? bit_waitqueue+0x30/0x30
   kernel:  ? fsnotify_grab_connector+0x3c/0x60
   kernel:  ? __sys_sendmsg+0x51/0x90
   kernel:  ? do_syscall_64+0x74/0x180
   kernel:  ? entry_SYSCALL_64_after_hwframe+0x3d/0xa2
   kernel: Code: 00 00 48 89 87 00 02 00 00 8b 87 a0 01 00 00 85 c0 0f 84 84 00 00 00 31 ed 48 63 dd 83 c5 01 48 c1 e3 06 49 03 9c 24 90 01 00 00 <48> 8b 73 08 48 8b 3b e8 6c 9a 4f f6 48 8d 43 10 48 c7 03 00 00
   kernel: RIP: fq_codel_reset+0x58/0xd0 [sch_fq_codel] RSP: ffffbfbf4c1fb620
   kernel: CR2: 0000000000000008
   kernel: ---[ end trace e81a62bede66274e ]---

This is caused because flows_cnt is non-zero, but flows hasn't been
initialized. fq_codel_init has left the private data in a partially
initialized state.

To fix this, reset flows_cnt to 0 when we fail to initialize.
Additionally, to make the state more consistent, also cleanup the flows
pointer when the allocation of backlogs fails.

This fixes the NULL pointer dereference, since both the for-loop and
memset in fq_codel_reset will be no-ops when flow_cnt is zero.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-12 12:32:09 -07:00
..
6lowpan
9p treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
802
8021q net: fix use-after-free in GRO with ESP 2018-07-02 20:34:04 +09:00
appletalk Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
atm Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
ax25 Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
batman-adv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-05-26 19:46:15 -04:00
bluetooth Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
bpf bpf: making bpf_prog_test run aware of possible data_end ptr change 2018-04-18 23:34:16 +02:00
bpfilter bpfilter: include bpfilter_umh in assembly instead of using objcopy 2018-06-28 21:39:16 +09:00
bridge Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-06-16 07:39:34 +09:00
caif Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
can Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
ceph The main piece is a set of libceph changes that revamps how OSD 2018-06-15 07:24:58 +09:00
core Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2018-07-08 13:06:55 +09:00
dcb treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
dccp Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
decnet Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
dns_resolver KEYS: DNS: limit the length of option strings 2018-04-17 15:17:41 -04:00
dsa net: dsa: add error handling for pskb_trim_rcsum 2018-06-11 14:19:38 -07:00
ethernet net: core: rework basic flow dissection helper 2018-05-08 00:02:36 -04:00
hsr
ieee802154 ieee802154: 6lowpan: set IFLA_LINK 2018-07-05 11:13:17 +02:00
ife net: sched: ife: check on metadata length 2018-04-22 21:12:00 -04:00
ipv4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2018-07-09 14:23:13 -07:00
ipv6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2018-07-09 14:23:13 -07:00
iucv Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
kcm Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
key Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
l2tp Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
l3mdev
lapb
llc Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
mac80211 mac80211: disable BHs/preemption in ieee80211_tx_control_port() 2018-06-29 09:39:08 +02:00
mac802154 net/mac802154: disambiguate mac80215 vs mac802154 trace events 2018-03-28 22:55:18 +02:00
mpls net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
ncsi net/ncsi: Use netdev_dbg for debug messages 2018-06-20 07:26:58 +09:00
netfilter netfilter: nf_conntrack: Fix possible possible crash on module loading. 2018-07-09 18:04:11 +02:00
netlabel audit: use inline function to get audit context 2018-05-14 17:24:18 -04:00
netlink Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
netrom Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
nfc Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
nsh nsh: fix infinite loop 2018-05-04 12:54:38 -04:00
openvswitch treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
packet Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
phonet Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
psample
qrtr net: qrtr: Reset the node and port ID of broadcast messages 2018-07-05 20:20:03 +09:00
rds rds: clean up loopback rds_connections on netns deletion 2018-06-27 10:11:03 +09:00
rfkill rfkill: Create rfkill-none LED trigger 2018-05-23 11:26:45 +02:00
rose Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
rxrpc Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
sched sch_fq_codel: zero q->flows_cnt when fq_codel_init fails 2018-07-12 12:32:09 -07:00
sctp sctp: fix the issue that pathmtu may be set lower than MINSEGMENT 2018-07-04 21:36:34 +09:00
smc net/smc: reduce sock_put() for fallback sockets 2018-07-07 20:25:13 +09:00
strparser strparser: Remove early eaten to fix full tcp receive buffer stall 2018-06-28 21:37:26 +09:00
sunrpc NFS client bugfixes for Linux 4.18 2018-06-22 06:21:34 +09:00
switchdev
tipc tipc: make function tipc_net_finalize() thread safe 2018-07-07 19:49:02 +09:00
tls tls: fix skb_to_sgvec returning unhandled error. 2018-07-03 23:26:47 +09:00
unix Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
vmw_vsock Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
wimax
wireless nl80211: check nla_parse_nested() return values 2018-06-29 09:44:51 +02:00
x25 Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
xdp xsk: fix potential race in SKB TX completion code 2018-07-02 18:37:12 -07:00
xfrm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
compat.c net: support compat 64-bit time in {s,g}etsockopt 2018-04-27 19:46:06 -04:00
Kconfig net: Introduce generic failover module 2018-05-28 22:59:54 -04:00
Makefile bpfilter: check compiler capability in Kconfig 2018-06-28 13:36:39 +09:00
socket.c net: handle NULL ->poll gracefully 2018-06-29 06:51:51 -07:00
sysctl_net.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00