================================================================== BUG: KASAN: null-ptr-deref in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline] BUG: KASAN: null-ptr-deref in refcount_sub_and_test_checked+0x9d/0x310 lib/refcount.c:179 Read of size 4 at addr 000000000000002e by task syz-executor5/6376 CPU: 1 PID: 6376 Comm: syz-executor5 Not tainted 4.19.0-rc6+ #245 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113 kasan_report_error mm/kasan/report.c:352 [inline] kasan_report.cold.9+0x6d/0x309 mm/kasan/report.c:412 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267 kasan_check_read+0x11/0x20 mm/kasan/kasan.c:272 atomic_read include/asm-generic/atomic-instrumented.h:21 [inline] refcount_sub_and_test_checked+0x9d/0x310 lib/refcount.c:179 refcount_dec_and_test_checked+0x1a/0x20 lib/refcount.c:212 ip_fib_metrics_put include/net/ip.h:428 [inline] fib6_info_destroy_rcu+0x2ef/0x3e0 net/ipv6/ip6_fib.c:204 __rcu_reclaim kernel/rcu/rcu.h:236 [inline] rcu_do_batch kernel/rcu/tree.c:2576 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2880 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2847 [inline] rcu_process_callbacks+0xf23/0x2670 kernel/rcu/tree.c:2864 __do_softirq+0x30b/0xad8 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x17f/0x1c0 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1cb/0x760 arch/x86/kernel/apic/apic.c:1056 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:864 RIP: 0010:debug_lockdep_rcu_enabled+0x79/0x90 kernel/rcu/update.c:254 Code: 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 1c 8b 05 72 3f 08 08 85 c0 74 07 e8 29 ff ff ff 5d c3 <31> c0 5d c3 e8 fe 5d 5a 00 eb ad e8 f7 5d 5a 00 eb dd 0f 1f 44 00 RSP: 0018:ffff880192fe7b20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: 0000000000001342 RCX: 0000000000000000 RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffffffff896fe800 RBP: ffff880192fe7b20 R08: 0000000000000000 R09: 0000000000000000 R10: fffffbfff1460609 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffed00325fcf78 R15: 000000000000a09c rcu_read_lock include/linux/rcupdate.h:630 [inline] bpf_test_run_one net/bpf/test_run.c:20 [inline] bpf_test_run+0x36c/0x5a0 net/bpf/test_run.c:43 bpf_prog_test_run_skb+0x634/0xb40 net/bpf/test_run.c:147 bpf_prog_test_run+0x130/0x1a0 kernel/bpf/syscall.c:1760 __do_sys_bpf kernel/bpf/syscall.c:2397 [inline] __se_sys_bpf kernel/bpf/syscall.c:2341 [inline] __x64_sys_bpf+0x3d8/0x510 kernel/bpf/syscall.c:2341 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457579 Code: 1d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 eb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fb929a78c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457579 RDX: 0000000000000028 RSI: 0000000020000100 RDI: 000000000000000a RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb929a796d4 R13: 00000000004bd8a6 R14: 00000000004cc208 R15: 00000000ffffffff ==================================================================