=====================================================
BUG: KMSAN: uninit-value in sctp_assoc_bh_rcv+0x34e/0xbc0 net/sctp/associola.c:987
 sctp_assoc_bh_rcv+0x34e/0xbc0 net/sctp/associola.c:987
 sctp_inq_push+0x2a6/0x350 net/sctp/inqueue.c:88
 sctp_rcv+0x39e5/0x3c90 net/sctp/input.c:243
 sctp6_rcv+0x48/0xc0 net/sctp/ipv6.c:1126
 ip6_protocol_deliver_rcu+0x1c86/0x2c60 net/ipv6/ip6_input.c:436
 ip6_input_finish net/ipv6/ip6_input.c:480 [inline]
 NF_HOOK include/linux/netfilter.h:317 [inline]
 ip6_input+0x136/0x470 net/ipv6/ip6_input.c:491
 dst_input include/net/dst.h:469 [inline]
 ip6_rcv_finish+0x5a4/0x960 net/ipv6/ip6_input.c:79
 NF_HOOK include/linux/netfilter.h:317 [inline]
 ipv6_rcv+0xf1/0x3c0 net/ipv6/ip6_input.c:309
 __netif_receive_skb_one_core net/core/dev.c:5977 [inline]
 __netif_receive_skb+0x1df/0xac0 net/core/dev.c:6090
 process_backlog+0x485/0xa00 net/core/dev.c:6442
 __napi_poll+0xdd/0x9c0 net/core/dev.c:7414
 napi_poll net/core/dev.c:7478 [inline]
 net_rx_action+0xa59/0x1ac0 net/core/dev.c:7605
 handle_softirqs+0x169/0x6e0 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x66/0x180 kernel/softirq.c:680
 irq_exit_rcu+0x12/0x20 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x84/0x90 arch/x86/kernel/apic/apic.c:1050
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:702
 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:95 [inline]
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x33/0x60 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 force_sig_info_to_task+0x6b3/0x7b0 kernel/signal.c:1324
 force_sig_fault_to_task kernel/signal.c:1699 [inline]
 force_sig_fault+0xce/0x100 kernel/signal.c:1704
 __bad_area_nosemaphore+0x5bc/0x9d0 arch/x86/mm/fault.c:823
 bad_area_nosemaphore+0x32/0x40 arch/x86/mm/fault.c:832
 do_user_addr_fault+0xa31/0x2560 arch/x86/mm/fault.c:1361
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x68/0xb0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x2b/0x30 arch/x86/include/asm/idtentry.h:623

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4154 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 __do_kmalloc_node mm/slub.c:4327 [inline]
 __kmalloc_node_track_caller_noprof+0x96d/0x12f0 mm/slub.c:4347
 kmalloc_reserve+0x22f/0x4b0 net/core/skbuff.c:601
 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:670
 alloc_skb include/linux/skbuff.h:1336 [inline]
 sctp_packet_pack net/sctp/output.c:472 [inline]
 sctp_packet_transmit+0x18a1/0x46d0 net/sctp/output.c:621
 sctp_outq_flush_transports net/sctp/outqueue.c:1173 [inline]
 sctp_outq_flush+0x1c7d/0x67c0 net/sctp/outqueue.c:1221
 sctp_outq_uncork+0x9e/0xc0 net/sctp/outqueue.c:764
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:-1 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1204 [inline]
 sctp_do_sm+0x8c8e/0x9720 net/sctp/sm_sideeffect.c:1175
 sctp_assoc_bh_rcv+0x88b/0xbc0 net/sctp/associola.c:1034
 sctp_inq_push+0x2a6/0x350 net/sctp/inqueue.c:88
 sctp_backlog_rcv+0x3c7/0xda0 net/sctp/input.c:331
 sk_backlog_rcv+0x13f/0x420 include/net/sock.h:1148
 __release_sock+0x1d3/0x330 net/core/sock.c:3213
 release_sock+0x6b/0x270 net/core/sock.c:3767
 sctp_wait_for_connect+0x458/0x820 net/sctp/socket.c:9367
 sctp_sendmsg_to_asoc+0x223a/0x2260 net/sctp/socket.c:1886
 sctp_sendmsg+0x3910/0x49f0 net/sctp/socket.c:2032
 inet_sendmsg+0x269/0x2a0 net/ipv4/af_inet.c:851
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x278/0x3d0 net/socket.c:727
 __sys_sendto+0x593/0x720 net/socket.c:2180
 __do_sys_sendto net/socket.c:2187 [inline]
 __se_sys_sendto net/socket.c:2183 [inline]
 __x64_sys_sendto+0x130/0x200 net/socket.c:2183
 x64_sys_call+0x3c0b/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 15934 Comm: syz.7.2584 Not tainted 6.16.0-rc4-syzkaller-00013-g66701750d556 #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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