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BUG: KMSAN: uninit-value in arch_atomic64_inc arch/x86/include/asm/atomic64_64.h:88 [inline]
BUG: KMSAN: uninit-value in arch_atomic_long_inc include/linux/atomic/atomic-long.h:161 [inline]
BUG: KMSAN: uninit-value in atomic_long_inc include/linux/atomic/atomic-instrumented.h:1429 [inline]
BUG: KMSAN: uninit-value in __ip6_make_skb+0x3388/0x3620 net/ipv6/ip6_output.c:1969
 arch_atomic64_inc arch/x86/include/asm/atomic64_64.h:88 [inline]
 arch_atomic_long_inc include/linux/atomic/atomic-long.h:161 [inline]
 atomic_long_inc include/linux/atomic/atomic-instrumented.h:1429 [inline]
 __ip6_make_skb+0x3388/0x3620 net/ipv6/ip6_output.c:1969
 ip6_finish_skb include/net/ipv6.h:1123 [inline]
 ip6_push_pending_frames+0x113/0x560 net/ipv6/ip6_output.c:2000
 rawv6_push_pending_frames+0xbd0/0xe20 net/ipv6/raw.c:585
 rawv6_sendmsg+0x2959/0x2e50 net/ipv6/raw.c:928
 inet_sendmsg+0x105/0x190 net/ipv4/af_inet.c:825
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg net/socket.c:747 [inline]
 __sys_sendto+0x80a/0xb00 net/socket.c:2142
 __do_sys_sendto net/socket.c:2154 [inline]
 __se_sys_sendto net/socket.c:2150 [inline]
 __x64_sys_sendto+0x125/0x1c0 net/socket.c:2150
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
 slab_post_alloc_hook+0x12d/0xb60 mm/slab.h:774
 slab_alloc_node mm/slub.c:3452 [inline]
 kmem_cache_alloc_node+0x543/0xab0 mm/slub.c:3497
 kmalloc_reserve+0x148/0x470 net/core/skbuff.c:520
 __alloc_skb+0x3a7/0x850 net/core/skbuff.c:606
 alloc_skb include/linux/skbuff.h:1277 [inline]
 __ip6_append_data+0x5254/0x6c70 net/ipv6/ip6_output.c:1697
 ip6_append_data+0x432/0x5a0 net/ipv6/ip6_output.c:1867
 rawv6_sendmsg+0x285d/0x2e50 net/ipv6/raw.c:921
 inet_sendmsg+0x105/0x190 net/ipv4/af_inet.c:825
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg net/socket.c:747 [inline]
 __sys_sendto+0x80a/0xb00 net/socket.c:2142
 __do_sys_sendto net/socket.c:2154 [inline]
 __se_sys_sendto net/socket.c:2150 [inline]
 __x64_sys_sendto+0x125/0x1c0 net/socket.c:2150
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

CPU: 1 PID: 13828 Comm: syz-executor.2 Tainted: G        W          6.3.0-rc3-syzkaller-g90ea0df61c98 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
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