=============================
WARNING: suspicious RCU usage
5.16.0-rc4-next-20211210-syzkaller #0 Not tainted
-----------------------------
kernel/sched/core.c:9545 Illegal context switch in RCU-bh read-side critical section!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
4 locks held by syz-executor.4/6599:
#0: ffff88806fe7be70 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1675 [inline]
#0: ffff88806fe7be70 (sk_lock-AF_INET6){+.+.}-{0:0}, at: sctp_sendmsg+0xf2a/0x1d30 net/sctp/socket.c:1966
#1: ffffffff8bb818a0 (rcu_read_lock){....}-{1:2}, at: ip6_route_output_flags+0x0/0x320 net/ipv6/route.c:778
#2: ffffffff8bb818a0 (rcu_read_lock){....}-{1:2}, at: ip6_pol_route+0x156/0x11e0 net/ipv6/route.c:2217
#3: ffffffff8bb81840 (rcu_read_lock_bh){....}-{1:2}, at: rt6_probe net/ipv6/route.c:632 [inline]
#3: ffffffff8bb81840 (rcu_read_lock_bh){....}-{1:2}, at: find_match.part.0+0x35a/0xd00 net/ipv6/route.c:752
stack backtrace:
CPU: 0 PID: 6599 Comm: syz-executor.4 Not tainted 5.16.0-rc4-next-20211210-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
__might_resched+0x235/0x2c0 kernel/sched/core.c:9545
might_alloc include/linux/sched/mm.h:256 [inline]
slab_pre_alloc_hook mm/slab.h:739 [inline]
slab_alloc_node mm/slub.c:3145 [inline]
slab_alloc mm/slub.c:3239 [inline]
kmem_cache_alloc_trace+0x25d/0x2c0 mm/slub.c:3256
kmalloc include/linux/slab.h:581 [inline]
kzalloc include/linux/slab.h:715 [inline]
ref_tracker_alloc+0xe1/0x430 lib/ref_tracker.c:74
netdev_tracker_alloc include/linux/netdevice.h:3860 [inline]
dev_hold_track include/linux/netdevice.h:3877 [inline]
rt6_probe net/ipv6/route.c:661 [inline]
find_match.part.0+0xac9/0xd00 net/ipv6/route.c:752
find_match net/ipv6/route.c:825 [inline]
__find_rr_leaf+0x17f/0xd20 net/ipv6/route.c:826
find_rr_leaf net/ipv6/route.c:847 [inline]
rt6_select net/ipv6/route.c:891 [inline]
fib6_table_lookup+0x649/0xa20 net/ipv6/route.c:2185
ip6_pol_route+0x1c5/0x11e0 net/ipv6/route.c:2221
pol_lookup_func include/net/ip6_fib.h:580 [inline]
fib6_rule_lookup+0x52a/0x6f0 net/ipv6/fib6_rules.c:120
ip6_route_output_flags_noref+0x2e2/0x380 net/ipv6/route.c:2629
ip6_route_output_flags+0x72/0x320 net/ipv6/route.c:2642
ip6_route_output include/net/ip6_route.h:98 [inline]
ip6_dst_lookup_tail+0x5ab/0x1620 net/ipv6/ip6_output.c:1070
ip6_dst_lookup_flow+0x8c/0x1d0 net/ipv6/ip6_output.c:1200
sctp_v6_get_dst+0x66c/0x1d60 net/sctp/ipv6.c:327
sctp_transport_route+0x125/0x350 net/sctp/transport.c:454
sctp_assoc_add_peer+0x6e6/0x14a0 net/sctp/associola.c:665
sctp_connect_new_asoc+0x1fc/0x770 net/sctp/socket.c:1096
sctp_sendmsg_new_asoc net/sctp/socket.c:1690 [inline]
sctp_sendmsg+0x13bc/0x1d30 net/sctp/socket.c:2000
inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:817
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:724
__sys_sendto+0x21c/0x320 net/socket.c:2036
__do_sys_sendto net/socket.c:2048 [inline]
__se_sys_sendto net/socket.c:2044 [inline]
__x64_sys_sendto+0xdd/0x1b0 net/socket.c:2044
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fded491ee99
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:00007fded3294168 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fded4a31f60 RCX: 00007fded491ee99
RDX: 000000000000a80c RSI: 0000000020847fff RDI: 0000000000000004
RBP: 00007fded4978ff1 R08: 000000002005ffe4 R09: 000000000000001c
R10: 00000000f5ffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffeaa8aff8f R14: 00007fded3294300 R15: 0000000000022000
BUG: sleeping function called from invalid context at include/linux/sched/mm.h:256
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 6599, name: syz-executor.4
preempt_count: 200, expected: 0
RCU nest depth: 2, expected: 0
4 locks held by syz-executor.4/6599:
#0: ffff88806fe7be70 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1675 [inline]
#0: ffff88806fe7be70 (sk_lock-AF_INET6){+.+.}-{0:0}, at: sctp_sendmsg+0xf2a/0x1d30 net/sctp/socket.c:1966
#1: ffffffff8bb818a0 (rcu_read_lock){....}-{1:2}, at: ip6_route_output_flags+0x0/0x320 net/ipv6/route.c:778
#2: ffffffff8bb818a0 (rcu_read_lock){....}-{1:2}, at: ip6_pol_route+0x156/0x11e0 net/ipv6/route.c:2217
#3: ffffffff8bb81840 (rcu_read_lock_bh){....}-{1:2}, at: rt6_probe net/ipv6/route.c:632 [inline]
#3: ffffffff8bb81840 (rcu_read_lock_bh){....}-{1:2}, at: find_match.part.0+0x35a/0xd00 net/ipv6/route.c:752
Preemption disabled at:
[] local_bh_disable include/linux/bottom_half.h:20 [inline]
[] rcu_read_lock_bh include/linux/rcupdate.h:746 [inline]
[] rt6_probe net/ipv6/route.c:633 [inline]
[] find_match.part.0+0x377/0xd00 net/ipv6/route.c:752
CPU: 0 PID: 6599 Comm: syz-executor.4 Not tainted 5.16.0-rc4-next-20211210-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
__might_resched.cold+0x222/0x26b kernel/sched/core.c:9583
might_alloc include/linux/sched/mm.h:256 [inline]
slab_pre_alloc_hook mm/slab.h:739 [inline]
slab_alloc_node mm/slub.c:3145 [inline]
slab_alloc mm/slub.c:3239 [inline]
kmem_cache_alloc_trace+0x25d/0x2c0 mm/slub.c:3256
kmalloc include/linux/slab.h:581 [inline]
kzalloc include/linux/slab.h:715 [inline]
ref_tracker_alloc+0xe1/0x430 lib/ref_tracker.c:74
netdev_tracker_alloc include/linux/netdevice.h:3860 [inline]
dev_hold_track include/linux/netdevice.h:3877 [inline]
rt6_probe net/ipv6/route.c:661 [inline]
find_match.part.0+0xac9/0xd00 net/ipv6/route.c:752
find_match net/ipv6/route.c:825 [inline]
__find_rr_leaf+0x17f/0xd20 net/ipv6/route.c:826
find_rr_leaf net/ipv6/route.c:847 [inline]
rt6_select net/ipv6/route.c:891 [inline]
fib6_table_lookup+0x649/0xa20 net/ipv6/route.c:2185
ip6_pol_route+0x1c5/0x11e0 net/ipv6/route.c:2221
pol_lookup_func include/net/ip6_fib.h:580 [inline]
fib6_rule_lookup+0x52a/0x6f0 net/ipv6/fib6_rules.c:120
ip6_route_output_flags_noref+0x2e2/0x380 net/ipv6/route.c:2629
ip6_route_output_flags+0x72/0x320 net/ipv6/route.c:2642
ip6_route_output include/net/ip6_route.h:98 [inline]
ip6_dst_lookup_tail+0x5ab/0x1620 net/ipv6/ip6_output.c:1070
ip6_dst_lookup_flow+0x8c/0x1d0 net/ipv6/ip6_output.c:1200
sctp_v6_get_dst+0x66c/0x1d60 net/sctp/ipv6.c:327
sctp_transport_route+0x125/0x350 net/sctp/transport.c:454
sctp_assoc_add_peer+0x6e6/0x14a0 net/sctp/associola.c:665
sctp_connect_new_asoc+0x1fc/0x770 net/sctp/socket.c:1096
sctp_sendmsg_new_asoc net/sctp/socket.c:1690 [inline]
sctp_sendmsg+0x13bc/0x1d30 net/sctp/socket.c:2000
inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:817
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:724
__sys_sendto+0x21c/0x320 net/socket.c:2036
__do_sys_sendto net/socket.c:2048 [inline]
__se_sys_sendto net/socket.c:2044 [inline]
__x64_sys_sendto+0xdd/0x1b0 net/socket.c:2044
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fded491ee99
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:00007fded3294168 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fded4a31f60 RCX: 00007fded491ee99
RDX: 000000000000a80c RSI: 0000000020847fff RDI: 0000000000000004
RBP: 00007fded4978ff1 R08: 000000002005ffe4 R09: 000000000000001c
R10: 00000000f5ffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffeaa8aff8f R14: 00007fded3294300 R15: 0000000000022000
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog