bisecting fixing commit since cbfa1702aaf69b2311ea1b35e04f113c48368c67
building syzkaller on b74c49a6af84e6ab50018024e8862263b1e0bd6d
testing commit cbfa1702aaf69b2311ea1b35e04f113c48368c67 with gcc (GCC) 8.1.0
kernel signature: fcd8978c3569386859d06a1d1814c52073bd7c0fb634d9b401cdcb4f89bd84e8
all runs: crashed: WARNING in sta_info_insert_rcu
testing current HEAD 3f2ecb86cb909da0b9157fd2952ad79924cbe5ae
testing commit 3f2ecb86cb909da0b9157fd2952ad79924cbe5ae with gcc (GCC) 8.1.0
kernel signature: 6077a4697393567a1da6c31e11fca7c75417f061f3b89534e055142e5b19c4d8
run #0: crashed: WARNING in sta_info_insert_rcu
run #1: crashed: WARNING in sta_info_insert_rcu
run #2: crashed: WARNING in sta_info_insert_rcu
run #3: crashed: WARNING in sta_info_insert_rcu
run #4: crashed: WARNING in sta_info_insert_rcu
run #5: crashed: WARNING in sta_info_insert_rcu
run #6: crashed: WARNING in sta_info_insert_rcu
run #7: crashed: WARNING in corrupted
run #8: crashed: WARNING in sta_info_insert_rcu
run #9: crashed: WARNING in sta_info_insert_rcu
revisions tested: 2, total time: 24m8.081070363s (build: 17m40.37252959s, test: 5m42.144857313s)
the crash still happens on HEAD
commit msg: Linux 4.14.212
crash: WARNING in sta_info_insert_rcu
IPv6: ADDRCONF(NETDEV_UP): veth0_macvtap: link is not ready
wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50
IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50
------------[ cut here ]------------
WARNING: CPU: 1 PID: 5 at net/mac80211/sta_info.c:482 sta_info_insert_check net/mac80211/sta_info.c:481 [inline]
WARNING: CPU: 1 PID: 5 at net/mac80211/sta_info.c:482 sta_info_insert_rcu+0x1b3/0x1db0 net/mac80211/sta_info.c:627
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 5 Comm: kworker/u4:0 Not tainted 4.14.212-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
ieee80211 phy8: mac80211_hwsim_start
Workqueue: phy2 ieee80211_iface_work
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x14b/0x1f1 lib/dump_stack.c:58
 panic+0x1b0/0x358 kernel/panic.c:183
 __warn.cold.7+0x25/0x2c kernel/panic.c:547
 report_bug+0x1a4/0x1f3 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:177 [inline]
 do_error_trap+0x1bd/0x310 arch/x86/kernel/traps.c:295
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:964
RIP: 0010:sta_info_insert_check net/mac80211/sta_info.c:481 [inline]
RIP: 0010:sta_info_insert_rcu+0x1b3/0x1db0 net/mac80211/sta_info.c:627
RSP: 0018:ffff8881f532faa8 EFLAGS: 00010202
RAX: 0000000000000005 RBX: ffff8881d8114a00 RCX: 00000000bd63276f
RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff8881d026200c
RBP: ffff8881f532fb60 R08: ffff8881f531c140 R09: ffffffff89537578
R10: ffff8881f532fa98 R11: ffff8881f531c140 R12: 00000000bd63377f
R13: ffff8881d0260f40 R14: ffff8881d5ca99e0 R15: ffff8881d8114a48
 ieee80211_ibss_finish_sta+0x1c4/0x280 net/mac80211/ibss.c:601
ieee80211 phy8: mac80211_hwsim_add_interface (type=1 mac_addr=02:00:00:00:08:00)
 ieee80211_ibss_work+0x255/0xcd0 net/mac80211/ibss.c:1692
ieee80211 phy8: mac80211_hwsim_bss_info_changed(changed=0xe vif->addr=02:00:00:00:08:00)
 ieee80211_iface_work+0x4a6/0x690 net/mac80211/iface.c:1383
ieee80211 phy8:   ERP_CTS_PROT: 0
 process_one_work+0x74f/0x1620 kernel/workqueue.c:2116
ieee80211 phy8:   ERP_PREAMBLE: 0
ieee80211 phy8:   ERP_SLOT: 0
 worker_thread+0xcc/0xed0 kernel/workqueue.c:2250
 kthread+0x338/0x400 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Kernel Offset: disabled
Rebooting in 86400 seconds..