=====================================================
BUG: KMSAN: uninit-value in __gre_xmit net/ipv4/ip_gre.c:469 [inline]
BUG: KMSAN: uninit-value in ipgre_xmit+0xdc2/0xe20 net/ipv4/ip_gre.c:662
 __gre_xmit net/ipv4/ip_gre.c:469 [inline]
 ipgre_xmit+0xdc2/0xe20 net/ipv4/ip_gre.c:662
 __netdev_start_xmit include/linux/netdevice.h:4910 [inline]
 netdev_start_xmit include/linux/netdevice.h:4924 [inline]
 xmit_one net/core/dev.c:3537 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3553
 __dev_queue_xmit+0x34eb/0x50f0 net/core/dev.c:4203
 dev_queue_xmit include/linux/netdevice.h:3088 [inline]
 __bpf_tx_skb net/core/filter.c:2129 [inline]
 __bpf_redirect_no_mac net/core/filter.c:2159 [inline]
 __bpf_redirect+0xe39/0x16f0 net/core/filter.c:2182
 ____bpf_clone_redirect net/core/filter.c:2453 [inline]
 bpf_clone_redirect+0x328/0x470 net/core/filter.c:2425
 ___bpf_prog_run+0x805/0xb260 kernel/bpf/core.c:1828
 __bpf_prog_run512+0xb5/0xe0 kernel/bpf/core.c:2051
 bpf_dispatcher_nop_func include/linux/bpf.h:1167 [inline]
 __bpf_prog_run include/linux/filter.h:600 [inline]
 bpf_prog_run include/linux/filter.h:607 [inline]
 bpf_test_run+0x474/0xaf0 net/bpf/test_run.c:422
 bpf_prog_test_run_skb+0x14e5/0x1f20 net/bpf/test_run.c:1028
 bpf_prog_test_run+0x6af/0xac0 kernel/bpf/syscall.c:3770
 __sys_bpf+0x649/0xd60 kernel/bpf/syscall.c:5155
 __do_sys_bpf kernel/bpf/syscall.c:5241 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5239 [inline]
 __ia32_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5239
 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+0x12f/0xb70 mm/slab.h:767
 slab_alloc_node mm/slub.c:3470 [inline]
 kmem_cache_alloc_node+0x577/0xa80 mm/slub.c:3515
 kmalloc_reserve+0x148/0x470 net/core/skbuff.c:559
 pskb_expand_head+0x226/0x1a10 net/core/skbuff.c:2042
 __skb_cow include/linux/skbuff.h:3571 [inline]
 skb_cow_head include/linux/skbuff.h:3605 [inline]
 ipgre_xmit+0x74a/0xe20 net/ipv4/ip_gre.c:638
 __netdev_start_xmit include/linux/netdevice.h:4910 [inline]
 netdev_start_xmit include/linux/netdevice.h:4924 [inline]
 xmit_one net/core/dev.c:3537 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3553
 __dev_queue_xmit+0x34eb/0x50f0 net/core/dev.c:4203
 dev_queue_xmit include/linux/netdevice.h:3088 [inline]
 __bpf_tx_skb net/core/filter.c:2129 [inline]
 __bpf_redirect_no_mac net/core/filter.c:2159 [inline]
 __bpf_redirect+0xe39/0x16f0 net/core/filter.c:2182
 ____bpf_clone_redirect net/core/filter.c:2453 [inline]
 bpf_clone_redirect+0x328/0x470 net/core/filter.c:2425
 ___bpf_prog_run+0x805/0xb260 kernel/bpf/core.c:1828
 __bpf_prog_run512+0xb5/0xe0 kernel/bpf/core.c:2051
 bpf_dispatcher_nop_func include/linux/bpf.h:1167 [inline]
 __bpf_prog_run include/linux/filter.h:600 [inline]
 bpf_prog_run include/linux/filter.h:607 [inline]
 bpf_test_run+0x474/0xaf0 net/bpf/test_run.c:422
 bpf_prog_test_run_skb+0x14e5/0x1f20 net/bpf/test_run.c:1028
 bpf_prog_test_run+0x6af/0xac0 kernel/bpf/syscall.c:3770
 __sys_bpf+0x649/0xd60 kernel/bpf/syscall.c:5155
 __do_sys_bpf kernel/bpf/syscall.c:5241 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5239 [inline]
 __ia32_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5239
 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: 7964 Comm: syz-executor.0 Not tainted 6.5.0-rc7-syzkaller-00104-g4f9e7fabf864 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
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