syzbot

R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007fb375bc5fa0 R14: 00007fb375bc5fa0 R15: 0000000000000003
 </TASK>
=============================
WARNING: suspicious RCU usage
syzkaller #0 Not tainted
-----------------------------
net/mac80211/mesh.c:1568 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.0.17/6118:
 #0: ffffffff90427550 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffff888035480768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: wiphy_lock include/net/cfg80211.h:6197 [inline]
 #1: ffff888035480768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: nl80211_pre_doit+0x71e/0xb10 net/wireless/nl80211.c:17436

stack backtrace:
CPU: 0 UID: 0 PID: 6118 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:120
 lockdep_rcu_suspicious+0x166/0x260 kernel/locking/lockdep.c:6876
 ieee80211_mesh_csa_beacon+0x2dd/0x340 net/mac80211/mesh.c:1568
 ieee80211_set_csa_beacon net/mac80211/cfg.c:4175 [inline]
 __ieee80211_channel_switch+0x1ae1/0x28d0 net/mac80211/cfg.c:4293
 rdev_channel_switch net/wireless/rdev-ops.h:1116 [inline]
 nl80211_channel_switch+0xc06/0x1020 net/wireless/nl80211.c:11099
 genl_family_rcv_msg_doit+0x209/0x2f0 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0x55c/0x800 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x158/0x420 net/netlink/af_netlink.c:2552
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x5a7/0x870 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg net/socket.c:729 [inline]
 ____sys_sendmsg+0xa95/0xc70 net/socket.c:2614
 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668
 __sys_sendmsg+0x16d/0x220 net/socket.c:2700
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb37598ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff036643a8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fb375bc5fa0 RCX: 00007fb37598ebe9
RDX: 0000000000000000 RSI: 0000200000000200 RDI: 0000000000000009
RBP: 00007fff03664400 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007fb375bc5fa0 R14: 00007fb375bc5fa0 R15: 0000000000000003
 </TASK>