================================================================== BUG: KASAN: use-after-free in skb_copy_bits+0x6f0/0x780 net/core/skbuff.c:2374 Read of size 4 at addr ffff88802e270bb0 by task ksoftirqd/0/13 CPU: 0 PID: 13 Comm: ksoftirqd/0 Not tainted 5.15.0-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 print_address_description.constprop.0.cold+0x8d/0x320 mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:450 skb_copy_bits+0x6f0/0x780 net/core/skbuff.c:2374 __skb_header_pointer include/linux/skbuff.h:3743 [inline] skb_header_pointer include/linux/skbuff.h:3752 [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:1845 [inline] nf_conntrack_in+0xfe8/0x15e0 net/netfilter/nf_conntrack_core.c:1918 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/0x3c0 net/ipv6/ip6_input.c:297 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5462 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5576 process_backlog+0x2a5/0x6c0 net/core/dev.c:6452 __napi_poll+0xaf/0x440 net/core/dev.c:7020 napi_poll net/core/dev.c:7087 [inline] net_rx_action+0x801/0xb40 net/core/dev.c:7174 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 run_ksoftirqd kernel/softirq.c:920 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:912 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 13: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:259 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:3234 [inline] kmem_cache_alloc_node+0x255/0x3f0 mm/slub.c:3270 __alloc_skb+0x215/0x340 net/core/skbuff.c:414 alloc_skb include/linux/skbuff.h:1126 [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:1163 sctp_outq_flush net/sctp/outqueue.c:1211 [inline] sctp_outq_uncork+0x185/0x200 net/sctp/outqueue.c:758 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+0x1da/0x270 net/sctp/inqueue.c:80 sctp_rcv+0xfe3/0x3290 net/sctp/input.c:256 sctp6_rcv+0x38/0x60 net/sctp/ipv6.c:1109 ip6_protocol_deliver_rcu+0x2e9/0x1ca0 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:460 [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+0x28c/0x3c0 net/ipv6/ip6_input.c:297 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5462 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5576 process_backlog+0x2a5/0x6c0 net/core/dev.c:6452 __napi_poll+0xaf/0x440 net/core/dev.c:7020 napi_poll net/core/dev.c:7087 [inline] net_rx_action+0x801/0xb40 net/core/dev.c:7174 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 Freed by task 13: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xff/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:1723 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1749 slab_free mm/slub.c:3513 [inline] kmem_cache_free+0x92/0x5e0 mm/slub.c:3529 kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:700 __kfree_skb net/core/skbuff.c:757 [inline] consume_skb net/core/skbuff.c:912 [inline] consume_skb+0xcf/0x160 net/core/skbuff.c:906 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+0x229/0x7d0 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+0x3665/0x4ed0 net/sctp/sm_sideeffect.c:1166 sctp_assoc_bh_rcv+0x386/0x6c0 net/sctp/associola.c:1054 sctp_inq_push+0x1da/0x270 net/sctp/inqueue.c:80 sctp_rcv+0xfe3/0x3290 net/sctp/input.c:256 sctp6_rcv+0x38/0x60 net/sctp/ipv6.c:1109 ip6_protocol_deliver_rcu+0x2e9/0x1ca0 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:460 [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+0x28c/0x3c0 net/ipv6/ip6_input.c:297 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5462 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5576 process_backlog+0x2a5/0x6c0 net/core/dev.c:6452 __napi_poll+0xaf/0x440 net/core/dev.c:7020 napi_poll net/core/dev.c:7087 [inline] net_rx_action+0x801/0xb40 net/core/dev.c:7174 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 The buggy address belongs to the object at ffff88802e270b40 which belongs to the cache skbuff_head_cache of size 232 The buggy address is located 112 bytes inside of 232-byte region [ffff88802e270b40, ffff88802e270c28) The buggy address belongs to the page: page:ffffea0000b89c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2e270 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea0001e400c0 dead000000000005 ffff888015bc7140 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 0x12a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY), pid 5867, ts 773749901984, free_ts 773744027470 prep_new_page mm/page_alloc.c:2418 [inline] get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4149 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5369 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2191 alloc_slab_page mm/slub.c:1793 [inline] allocate_slab mm/slub.c:1930 [inline] new_slab+0x32d/0x4a0 mm/slub.c:1993 ___slab_alloc+0x918/0xfe0 mm/slub.c:3022 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3109 slab_alloc_node mm/slub.c:3200 [inline] slab_alloc mm/slub.c:3242 [inline] kmem_cache_alloc+0x35c/0x3a0 mm/slub.c:3247 skb_clone+0x170/0x3c0 net/core/skbuff.c:1521 pskb_extract+0x29/0x2b0 net/core/skbuff.c:6344 rds_tcp_data_recv+0x600/0xc30 net/rds/tcp_recv.c:218 tcp_read_sock+0x25c/0x720 net/ipv4/tcp.c:1643 rds_tcp_read_sock net/rds/tcp_recv.c:276 [inline] rds_tcp_data_ready+0x257/0x6d0 net/rds/tcp_recv.c:325 tcp_data_ready+0x106/0x540 net/ipv4/tcp_input.c:4977 tcp_rcv_established+0x1b3a/0x2130 net/ipv4/tcp_input.c:5916 tcp_v6_do_rcv+0x461/0x1320 net/ipv6/tcp_ipv6.c:1521 tcp_v6_rcv+0x236d/0x2cb0 net/ipv6/tcp_ipv6.c:1764 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1338 [inline] free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1389 free_unref_page_prepare mm/page_alloc.c:3309 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3388 __vunmap+0x781/0xb70 mm/vmalloc.c:2632 free_work+0x58/0x70 mm/vmalloc.c:95 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff88802e270a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc ffff88802e270b00: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb >ffff88802e270b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802e270c00: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc ffff88802e270c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================