============================= WARNING: suspicious RCU usage 5.12.0-rc4-syzkaller #0 Not tainted ----------------------------- include/net/addrconf.h:314 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by syz-executor.2/15283: #0: ffff88806e2690a0 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1600 [inline] #0: ffff88806e2690a0 (sk_lock-AF_INET6){+.+.}-{0:0}, at: ipv6_get_msfilter+0xf8/0x220 net/ipv6/ipv6_sockglue.c:1064 stack backtrace: CPU: 0 PID: 15283 Comm: syz-executor.2 Not tainted 5.12.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 __in6_dev_get include/net/addrconf.h:314 [inline] __in6_dev_get include/net/addrconf.h:312 [inline] ip6_mc_find_dev_rtnl+0x1be/0x1f0 net/ipv6/mcast.c:310 ip6_mc_msfget+0x1be/0x830 net/ipv6/mcast.c:590 ipv6_get_msfilter+0x10c/0x220 net/ipv6/ipv6_sockglue.c:1065 do_ipv6_getsockopt.constprop.0+0x1675/0x2660 net/ipv6/ipv6_sockglue.c:1142 ipv6_getsockopt+0x13c/0x270 net/ipv6/ipv6_sockglue.c:1477 udpv6_getsockopt+0x5d/0x90 net/ipv6/udp.c:1638 __sys_getsockopt+0x21f/0x5f0 net/socket.c:2161 __do_sys_getsockopt net/socket.c:2176 [inline] __se_sys_getsockopt net/socket.c:2173 [inline] __x64_sys_getsockopt+0xba/0x150 net/socket.c:2173 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x466459 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb424bc1188 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000030 RSI: 0000000000000029 RDI: 0000000000000003 RBP: 00000000004bf9fb R08: 0000000020001000 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007fff1da0fdef R14: 00007fb424bc1300 R15: 0000000000022000