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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:1122 [inline]
 ip6_push_pending_frames+0x113/0x560 net/ipv6/ip6_output.c:2000
 rawv6_push_pending_frames+0xbd0/0xe20 net/ipv6/raw.c:583
 rawv6_sendmsg+0x2959/0x2e30 net/ipv6/raw.c:926
 inet_sendmsg+0x105/0x190 net/ipv4/af_inet.c:828
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0xa8f/0xe70 net/socket.c:2479
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2533
 __sys_sendmmsg+0x411/0xa50 net/socket.c:2619
 __do_sys_sendmmsg net/socket.c:2648 [inline]
 __se_sys_sendmmsg net/socket.c:2645 [inline]
 __x64_sys_sendmmsg+0xbc/0x120 net/socket.c:2645
 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:766
 slab_alloc_node mm/slub.c:3452 [inline]
 __kmem_cache_alloc_node+0x518/0x920 mm/slub.c:3491
 __do_kmalloc_node mm/slab_common.c:967 [inline]
 __kmalloc_node_track_caller+0x118/0x3c0 mm/slab_common.c:988
 kmalloc_reserve net/core/skbuff.c:492 [inline]
 __alloc_skb+0x3b8/0x900 net/core/skbuff.c:565
 alloc_skb include/linux/skbuff.h:1270 [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/0x2e30 net/ipv6/raw.c:919
 inet_sendmsg+0x105/0x190 net/ipv4/af_inet.c:828
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0xa8f/0xe70 net/socket.c:2479
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2533
 __sys_sendmmsg+0x411/0xa50 net/socket.c:2619
 __do_sys_sendmmsg net/socket.c:2648 [inline]
 __se_sys_sendmmsg net/socket.c:2645 [inline]
 __x64_sys_sendmmsg+0xbc/0x120 net/socket.c:2645
 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: 0 PID: 8623 Comm: syz-executor.2 Not tainted 6.2.0-syzkaller-81157-g944070199c5e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
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