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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:722 [inline]
 sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0xa24/0xe40 net/socket.c:2504
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2558
 __sys_sendmmsg+0x548/0xa50 net/socket.c:2637
 __compat_sys_sendmmsg net/compat.c:359 [inline]
 __do_compat_sys_sendmmsg net/compat.c:366 [inline]
 __se_compat_sys_sendmmsg net/compat.c:363 [inline]
 __ia32_compat_sys_sendmmsg+0xc8/0x140 net/compat.c:363
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

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+0x14b/0x3e0 net/core/skbuff.c:525
 __alloc_skb+0x3a7/0x850 net/core/skbuff.c:608
 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:722 [inline]
 sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0xa24/0xe40 net/socket.c:2504
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2558
 __sys_sendmmsg+0x548/0xa50 net/socket.c:2637
 __compat_sys_sendmmsg net/compat.c:359 [inline]
 __do_compat_sys_sendmmsg net/compat.c:366 [inline]
 __se_compat_sys_sendmmsg net/compat.c:363 [inline]
 __ia32_compat_sys_sendmmsg+0xc8/0x140 net/compat.c:363
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

CPU: 1 PID: 10324 Comm: syz-executor.4 Not tainted 6.3.0-rc1-syzkaller-ge61893130d87 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
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