================================================================== 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 udevd/3194 CPU: 0 PID: 3194 Comm: udevd 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:update_stack_state+0xb4/0x690 arch/x86/kernel/unwind_frame.c:210 Code: 89 f8 48 c1 e8 03 0f b6 04 10 84 c0 74 08 3c 03 0f 8e 96 04 00 00 41 8b 06 49 8d 7e 50 48 89 fa 48 c1 ea 03 89 85 24 ff ff ff <48> b8 00 00 00 00 00 fc ff df 80 3c 02 00 0f 85 04 05 00 00 49 8b RSP: 0018:ffff8801c82f7040 EFLAGS: 00000a02 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000001 RBX: ffff8801c82f7270 RCX: ffff8801c82f7220 RDX: 1ffff1003905ee58 RSI: ffff8801c82f7688 RDI: ffff8801c82f72c0 RBP: ffff8801c82f7148 R08: ffff8801c82f72a8 R09: ffff8801c82ec140 R10: ffffed003905ee58 R11: ffff8801c82f72c7 R12: 1ffff1003905ee10 R13: ffff8801c82f7688 R14: ffff8801c82f7270 R15: ffff8801c82f72c0 unwind_next_frame.part.7+0x1ae/0x9e0 arch/x86/kernel/unwind_frame.c:329 unwind_next_frame+0x3e/0x50 arch/x86/kernel/unwind_frame.c:287 __save_stack_trace+0x7d/0xf0 arch/x86/kernel/stacktrace.c:44 save_stack_trace+0x1a/0x20 arch/x86/kernel/stacktrace.c:60 save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 slab_post_alloc_hook mm/slab.h:444 [inline] slab_alloc_node mm/slab.c:3335 [inline] kmem_cache_alloc_node_trace+0x135/0x740 mm/slab.c:3661 __do_kmalloc_node mm/slab.c:3681 [inline] __kmalloc_node_track_caller+0x33/0x70 mm/slab.c:3696 __kmalloc_reserve.isra.39+0x41/0xe0 net/core/skbuff.c:137 __alloc_skb+0x155/0x770 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:997 [inline] alloc_uevent_skb+0x84/0x1da lib/kobject_uevent.c:288 uevent_net_broadcast_untagged lib/kobject_uevent.c:324 [inline] kobject_uevent_net_broadcast lib/kobject_uevent.c:406 [inline] kobject_uevent_env+0xa52/0x101e lib/kobject_uevent.c:587 kobject_synth_uevent.cold.5+0x10e/0x17e lib/kobject_uevent.c:208 uevent_store+0x26/0x70 drivers/base/core.c:1070 dev_attr_store+0x5e/0x90 drivers/base/core.c:781 sysfs_kf_write+0x118/0x170 fs/sysfs/file.c:139 kernfs_fop_write+0x2ba/0x480 fs/kernfs/file.c:316 __vfs_write+0x119/0x9f0 fs/read_write.c:485 vfs_write+0x1fc/0x560 fs/read_write.c:549 ksys_write+0x101/0x260 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7ff6f7150370 Code: 73 01 c3 48 8b 0d c8 4a 2b 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 83 3d 85 a2 2b 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 0e 8a 01 00 48 89 04 24 RSP: 002b:00007ffc76926b68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000160fad0 RCX: 00007ff6f7150370 RDX: 0000000000000006 RSI: 000000000041f4f9 RDI: 000000000000000b RBP: 000000000160fe90 R08: 000000000041f4f1 R09: 00007ff6f71a67d0 R10: 7269762f73656369 R11: 0000000000000246 R12: 000000000000000b R13: 0000000000000000 R14: 000000000160fad0 R15: 000000000160a250 ==================================================================