audit: type=1400 audit(1516713690.534:8): avc: denied { map_create } for pid=3656 comm="syzkaller241398" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=bpf permissive=1 ============================= WARNING: suspicious RCU usage 4.15.0-rc8+ #1 Not tainted ----------------------------- ./include/linux/rcupdate.h:302 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by syzkaller241398/3656: #0: (rcu_read_lock){....}, at: [<00000000eacbc80c>] map_get_next_key kernel/bpf/syscall.c:836 [inline] #0: (rcu_read_lock){....}, at: [<00000000eacbc80c>] SYSC_bpf kernel/bpf/syscall.c:1881 [inline] #0: (rcu_read_lock){....}, at: [<00000000eacbc80c>] SyS_bpf+0x1105/0x4860 kernel/bpf/syscall.c:1846 stack backtrace: CPU: 1 PID: 3656 Comm: syzkaller241398 Not tainted 4.15.0-rc8+ #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 lockdep_rcu_suspicious+0x123/0x170 kernel/locking/lockdep.c:4585 rcu_preempt_sleep_check include/linux/rcupdate.h:301 [inline] ___might_sleep+0x385/0x470 kernel/sched/core.c:6025 __might_sleep+0x95/0x190 kernel/sched/core.c:6013 slab_pre_alloc_hook mm/slab.h:419 [inline] slab_alloc mm/slab.c:3368 [inline] __do_kmalloc mm/slab.c:3706 [inline] __kmalloc+0x2c5/0x760 mm/slab.c:3717 kmalloc include/linux/slab.h:504 [inline] trie_get_next_key+0x517/0xf10 kernel/bpf/lpm_trie.c:626 map_get_next_key kernel/bpf/syscall.c:842 [inline] SYSC_bpf kernel/bpf/syscall.c:1881 [inline] SyS_bpf+0x11b4/0x4860 kernel/bpf/syscall.c:1846 entry_SYSCALL_64_fastpath+0x29/0xa0 RIP: 0033:0x4407f9