=====================================================
BUG: KMSAN: uninit-value in tipc_rcv+0x17fa/0x1ea0 net/tipc/node.c:2132
 tipc_rcv+0x17fa/0x1ea0 net/tipc/node.c:2132
 tipc_l2_rcv_msg+0x213/0x320 net/tipc/bearer.c:668
 __netif_receive_skb_list_ptype net/core/dev.c:6039 [inline]
 __netif_receive_skb_list_core+0x133b/0x16b0 net/core/dev.c:6081
 __netif_receive_skb_list net/core/dev.c:6133 [inline]
 netif_receive_skb_list_internal+0xee7/0x1530 net/core/dev.c:6224
 gro_normal_list include/net/gro.h:532 [inline]
 gro_flush_normal include/net/gro.h:540 [inline]
 napi_complete_done+0x3fb/0x7d0 net/core/dev.c:6593
 napi_complete include/linux/netdevice.h:589 [inline]
 tun_get_user+0x4c0d/0x6ca0 drivers/net/tun.c:1921
 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1996
 do_iter_readv_writev+0x9cd/0xc00 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __ia32_sys_writev+0x9c/0xf0 fs/read_write.c:1168
 ia32_sys_call+0x2f6a/0x4310 arch/x86/include/generated/asm/syscalls_32.h:147
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x150 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4186 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 kmem_cache_alloc_node_noprof+0x818/0xf00 mm/slub.c:4281
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:578
 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:669
 napi_alloc_skb+0xc1/0x740 net/core/skbuff.c:811
 napi_get_frags+0xab/0x250 net/core/gro.c:673
 tun_napi_alloc_frags drivers/net/tun.c:1404 [inline]
 tun_get_user+0x134f/0x6ca0 drivers/net/tun.c:1784
 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1996
 do_iter_readv_writev+0x9cd/0xc00 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __ia32_sys_writev+0x9c/0xf0 fs/read_write.c:1168
 ia32_sys_call+0x2f6a/0x4310 arch/x86/include/generated/asm/syscalls_32.h:147
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x150 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

CPU: 1 UID: 0 PID: 6527 Comm: syz.2.197 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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