[FS#1443] Kernel Oops when Fragmentation is Set

[LEDE Bugs]

The following task has a new comment added:

FS#1443 - Kernel Oops when Fragmentation is Set
User who did this - Tom Li (biergaizi)

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Still occurs in the latest trunk.

[ 4777.620819] ------------[ cut here ]------------
[ 4777.625609] WARNING: CPU: 0 PID: 0 at backports-2017-11-01/net/mac80211/tx.c:942 ieee80211_probereq_get+0x448/0x1648 [mac80211]
[ 4777.637081] Modules linked in: ath9k ath9k_common pppoe ppp_async ath9k_hw ath pppox ppp_generic nf_conntrack_ipv6 mac80211 iptable_nat ipt_REJECT ipt_MASQUERADE cfg80211 xt_time xt_tcpudp xt_state xt_nat xt_multiport xt_mark xt_mac xt_limit xt_conntrack xt_comment xt_TCPMSS xt_REDIRECT xt_LOG xt_CT slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables x_tables gpio_button_hotplug
[ 4777.694583] CPU: 0 PID: 0 Comm: swapper Not tainted 4.9.87 #0
[ 4777.700319] Stack : 804d74fa 00000031 00000000 00000001 8047b6d4 8047b347 8042cb38 00000000
[ 4777.708716]         804d3640 000003ae 0000001a 80d60b80 80d4e008 800a8e50 80432368 80480000
[ 4777.717102]         00000003 000003ae 80430520 81809b1c 80d4e008 800d75bc 804d74fa 00000073
[ 4777.725492]         00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[ 4777.733899]         00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[ 4777.742297]         ...
[ 4777.744744] Call Trace:
[ 4777.747208] [] show_stack+0x70/0x8c
[ 4777.751580] [] __warn+0x110/0x118
[ 4777.755757] [] warn_slowpath_null+0x1c/0x2c
[ 4777.760926] [] ieee80211_probereq_get+0x448/0x1648 [mac80211]
[ 4777.767581] ---[ end trace 4dfad80db5fe28ce ]---

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More information can be found at the following URL:
https://bugs.openwrt.org/index.php?do=details&task_id=1443#comment4501