==================================================================
BUG: KASAN: use-after-free in skb_copy_bits+0x6f0/0x780 net/core/skbuff.c:2396
Read of size 4 at addr ffff88804234f7f0 by task kworker/u4:5/1379

CPU: 1 PID: 1379 Comm: kworker/u4:5 Not tainted 5.17.0-rc1-syzkaller-00228-g3aa430d33b8d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255
 __kasan_report mm/kasan/report.c:442 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
 skb_copy_bits+0x6f0/0x780 net/core/skbuff.c:2396
 __skb_header_pointer include/linux/skbuff.h:3782 [inline]
 skb_header_pointer include/linux/skbuff.h:3791 [inline]
 do_basic_checks net/netfilter/nf_conntrack_proto_sctp.c:174 [inline]
 nf_conntrack_sctp_packet+0xe34/0x2500 net/netfilter/nf_conntrack_proto_sctp.c:383
 nf_conntrack_handle_packet net/netfilter/nf_conntrack_core.c:1847 [inline]
 nf_conntrack_in+0xeb5/0x17f0 net/netfilter/nf_conntrack_core.c:1920
 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
 nf_hook_slow+0xc5/0x1e0 net/netfilter/core.c:619
 nf_hook.constprop.0+0x3ac/0x650 include/linux/netfilter.h:262
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ipv6_rcv+0x9e/0x3b0 net/ipv6/ip6_input.c:297
 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5351
 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5465
 process_backlog+0x2a5/0x6c0 net/core/dev.c:5797
 __napi_poll+0xaf/0x440 net/core/dev.c:6365
 napi_poll net/core/dev.c:6432 [inline]
 net_rx_action+0x801/0xb40 net/core/dev.c:6519
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_acquire+0x1ef/0x510 kernel/locking/lockdep.c:5607
Code: 2f a5 7e 83 f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24
RSP: 0018:ffffc900061cfba8 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff92000c39f77 RCX: 81e63993641d93b9
RDX: 1ffff11003b37c2b RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8ffbd947
R10: fffffbfff1ff7b28 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: ffffffff8bb83ae0 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:268 [inline]
 rcu_read_lock include/linux/rcupdate.h:694 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0x12d/0xfa0 net/batman-adv/network-coding.c:719
 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307
 worker_thread+0x657/0x1110 kernel/workqueue.c:2454
 kthread+0x2e9/0x3a0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Allocated by task 1379:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:436 [inline]
 __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:469
 kasan_slab_alloc include/linux/kasan.h:260 [inline]
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc_node mm/slub.c:3230 [inline]
 kmem_cache_alloc_node+0x255/0x3f0 mm/slub.c:3266
 __alloc_skb+0x215/0x340 net/core/skbuff.c:414
 alloc_skb include/linux/skbuff.h:1158 [inline]
 sctp_packet_pack net/sctp/output.c:471 [inline]
 sctp_packet_transmit+0xcca/0x3070 net/sctp/output.c:620
 sctp_outq_flush_transports+0x406/0x7b0 net/sctp/outqueue.c:1166
 sctp_outq_flush net/sctp/outqueue.c:1214 [inline]
 sctp_outq_uncork+0x185/0x200 net/sctp/outqueue.c:761
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1812 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1195 [inline]
 sctp_do_sm+0x745/0x4ed0 net/sctp/sm_sideeffect.c:1166
 sctp_assoc_bh_rcv+0x386/0x6c0 net/sctp/associola.c:1054
 sctp_inq_push+0x1d2/0x270 net/sctp/inqueue.c:80
 sctp_rcv+0x1018/0x32f0 net/sctp/input.c:256
 sctp6_rcv+0x38/0x60 net/sctp/ipv6.c:1109
 ip6_protocol_deliver_rcu+0x2e9/0x1d10 net/ipv6/ip6_input.c:422
 ip6_input_finish+0x62/0x170 net/ipv6/ip6_input.c:463
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ip6_input+0x9c/0xd0 net/ipv6/ip6_input.c:472
 dst_input include/net/dst.h:461 [inline]
 ip6_rcv_finish net/ipv6/ip6_input.c:76 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ipv6_rcv+0x27f/0x3b0 net/ipv6/ip6_input.c:297
 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5351
 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5465
 process_backlog+0x2a5/0x6c0 net/core/dev.c:5797
 __napi_poll+0xaf/0x440 net/core/dev.c:6365
 napi_poll net/core/dev.c:6432 [inline]
 net_rx_action+0x801/0xb40 net/core/dev.c:6519
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558

Freed by task 1379:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 kasan_set_track+0x21/0x30 mm/kasan/common.c:45
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free+0x130/0x160 mm/kasan/common.c:328
 kasan_slab_free include/linux/kasan.h:236 [inline]
 slab_free_hook mm/slub.c:1728 [inline]
 slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754
 slab_free mm/slub.c:3509 [inline]
 kmem_cache_free+0xd8/0x340 mm/slub.c:3526
 kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:700
 __kfree_skb net/core/skbuff.c:757 [inline]
 consume_skb net/core/skbuff.c:914 [inline]
 consume_skb+0xcf/0x160 net/core/skbuff.c:908
 sctp_chunk_destroy net/sctp/sm_make_chunk.c:1503 [inline]
 sctp_chunk_put+0x1c0/0x2d0 net/sctp/sm_make_chunk.c:1530
 sctp_inq_free+0x17f/0x260 net/sctp/inqueue.c:56
 sctp_association_free+0x221/0x7d0 net/sctp/associola.c:348
 sctp_cmd_delete_tcb net/sctp/sm_sideeffect.c:940 [inline]
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1324 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1195 [inline]
 sctp_do_sm+0x365d/0x4ed0 net/sctp/sm_sideeffect.c:1166
 sctp_assoc_bh_rcv+0x386/0x6c0 net/sctp/associola.c:1054
 sctp_inq_push+0x1d2/0x270 net/sctp/inqueue.c:80
 sctp_rcv+0x1018/0x32f0 net/sctp/input.c:256
 sctp6_rcv+0x38/0x60 net/sctp/ipv6.c:1109
 ip6_protocol_deliver_rcu+0x2e9/0x1d10 net/ipv6/ip6_input.c:422
 ip6_input_finish+0x62/0x170 net/ipv6/ip6_input.c:463
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ip6_input+0x9c/0xd0 net/ipv6/ip6_input.c:472
 dst_input include/net/dst.h:461 [inline]
 ip6_rcv_finish net/ipv6/ip6_input.c:76 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ipv6_rcv+0x27f/0x3b0 net/ipv6/ip6_input.c:297
 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5351
 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5465
 process_backlog+0x2a5/0x6c0 net/core/dev.c:5797
 __napi_poll+0xaf/0x440 net/core/dev.c:6365
 napi_poll net/core/dev.c:6432 [inline]
 net_rx_action+0x801/0xb40 net/core/dev.c:6519
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558

The buggy address belongs to the object at ffff88804234f780
 which belongs to the cache skbuff_head_cache of size 232
The buggy address is located 112 bytes inside of
 232-byte region [ffff88804234f780, ffff88804234f868)
The buggy address belongs to the page:
page:ffffea000108d3c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4234f
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 0000000000000000 dead000000000122 ffff888144bed000
raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 1379, ts 323954313079, free_ts 310293432126
 prep_new_page mm/page_alloc.c:2434 [inline]
 get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389
 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2271
 alloc_slab_page mm/slub.c:1799 [inline]
 allocate_slab mm/slub.c:1944 [inline]
 new_slab+0x28a/0x3b0 mm/slub.c:2004
 ___slab_alloc+0x87c/0xe90 mm/slub.c:3018
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105
 slab_alloc_node mm/slub.c:3196 [inline]
 kmem_cache_alloc_node+0x122/0x3f0 mm/slub.c:3266
 __alloc_skb+0x215/0x340 net/core/skbuff.c:414
 alloc_skb include/linux/skbuff.h:1158 [inline]
 _sctp_make_chunk+0x50/0x260 net/sctp/sm_make_chunk.c:1443
 sctp_make_control+0x30/0x2d0 net/sctp/sm_make_chunk.c:1490
 sctp_make_sack+0x18f/0x500 net/sctp/sm_make_chunk.c:785
 sctp_gen_sack net/sctp/sm_sideeffect.c:206 [inline]
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1355 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1195 [inline]
 sctp_do_sm+0x3ed5/0x4ed0 net/sctp/sm_sideeffect.c:1166
 sctp_assoc_bh_rcv+0x386/0x6c0 net/sctp/associola.c:1054
 sctp_inq_push+0x1d2/0x270 net/sctp/inqueue.c:80
 sctp_rcv+0x1018/0x32f0 net/sctp/input.c:256
 sctp6_rcv+0x38/0x60 net/sctp/ipv6.c:1109
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1352 [inline]
 free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404
 free_unref_page_prepare mm/page_alloc.c:3325 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3404
 __vunmap+0x798/0xc50 mm/vmalloc.c:2635
 __vfree+0x3c/0xd0 mm/vmalloc.c:2683
 __vmalloc_area_node mm/vmalloc.c:3016 [inline]
 __vmalloc_node_range+0xe4c/0x1060 mm/vmalloc.c:3107
 __vmalloc_node mm/vmalloc.c:3157 [inline]
 vzalloc+0x67/0x80 mm/vmalloc.c:3227
 xt_counters_alloc+0x4c/0x70 net/netfilter/x_tables.c:1379
 __do_replace+0x9a/0x870 net/ipv4/netfilter/ip_tables.c:1049
 do_replace net/ipv4/netfilter/ip_tables.c:1140 [inline]
 do_ipt_set_ctl+0x901/0xb80 net/ipv4/netfilter/ip_tables.c:1630
 nf_setsockopt+0x83/0xe0 net/netfilter/nf_sockopt.c:101
 ip_setsockopt+0x3c3/0x3a90 net/ipv4/ip_sockglue.c:1444
 tcp_setsockopt+0x136/0x2520 net/ipv4/tcp.c:3689
 __sys_setsockopt+0x2db/0x610 net/socket.c:2180
 __do_sys_setsockopt net/socket.c:2191 [inline]
 __se_sys_setsockopt net/socket.c:2188 [inline]
 __x64_sys_setsockopt+0xba/0x150 net/socket.c:2188
 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

Memory state around the buggy address:
 ffff88804234f680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804234f700: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
>ffff88804234f780: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff88804234f800: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
 ffff88804234f880: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	a5                   	movsl  %ds:(%rsi),%es:(%rdi)
   1:	7e 83                	jle    0xffffff86
   3:	f8                   	clc
   4:	01 0f                	add    %ecx,(%rdi)
   6:	85 b4 02 00 00 9c 58 	test   %esi,0x589c0000(%rdx,%rax,1)
   d:	f6 c4 02             	test   $0x2,%ah
  10:	0f 85 9f 02 00 00    	jne    0x2b5
  16:	48 83 7c 24 08 00    	cmpq   $0x0,0x8(%rsp)
  1c:	74 01                	je     0x1f
  1e:	fb                   	sti
  1f:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  26:	fc ff df
* 29:	48 01 c3             	add    %rax,%rbx <-- trapping instruction
  2c:	48 c7 03 00 00 00 00 	movq   $0x0,(%rbx)
  33:	48 c7 43 08 00 00 00 	movq   $0x0,0x8(%rbx)
  3a:	00
  3b:	48                   	rex.W
  3c:	8b                   	.byte 0x8b
  3d:	84                   	.byte 0x84
  3e:	24                   	.byte 0x24