=====================================================
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:4889 [inline]
 netdev_start_xmit include/linux/netdevice.h:4903 [inline]
 xmit_one net/core/dev.c:3544 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3560
 __dev_queue_xmit+0x34d0/0x52a0 net/core/dev.c:4340
 dev_queue_xmit include/linux/netdevice.h:3082 [inline]
 __bpf_tx_skb net/core/filter.c:2129 [inline]
 __bpf_redirect_no_mac net/core/filter.c:2159 [inline]
 __bpf_redirect+0xdf7/0x1700 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+0x2180/0xdb80 kernel/bpf/core.c:1954
 __bpf_prog_run512+0xb5/0xe0 kernel/bpf/core.c:2195
 bpf_dispatcher_nop_func include/linux/bpf.h:1181 [inline]
 __bpf_prog_run include/linux/filter.h:609 [inline]
 bpf_prog_run include/linux/filter.h:616 [inline]
 bpf_test_run+0x474/0xaf0 net/bpf/test_run.c:423
 bpf_prog_test_run_skb+0x14e5/0x1f20 net/bpf/test_run.c:1045
 bpf_prog_test_run+0x6af/0xac0 kernel/bpf/syscall.c:3996
 __sys_bpf+0x649/0xd60 kernel/bpf/syscall.c:5353
 __do_sys_bpf kernel/bpf/syscall.c:5439 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5437 [inline]
 __ia32_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5437
 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:3478 [inline]
 kmem_cache_alloc_node+0x577/0xa80 mm/slub.c:3523
 kmalloc_reserve+0x148/0x470 net/core/skbuff.c:559
 pskb_expand_head+0x226/0x1a00 net/core/skbuff.c:2087
 __skb_cow include/linux/skbuff.h:3586 [inline]
 skb_cow_head include/linux/skbuff.h:3620 [inline]
 ipgre_xmit+0x74a/0xe20 net/ipv4/ip_gre.c:638
 __netdev_start_xmit include/linux/netdevice.h:4889 [inline]
 netdev_start_xmit include/linux/netdevice.h:4903 [inline]
 xmit_one net/core/dev.c:3544 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3560
 __dev_queue_xmit+0x34d0/0x52a0 net/core/dev.c:4340
 dev_queue_xmit include/linux/netdevice.h:3082 [inline]
 __bpf_tx_skb net/core/filter.c:2129 [inline]
 __bpf_redirect_no_mac net/core/filter.c:2159 [inline]
 __bpf_redirect+0xdf7/0x1700 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+0x2180/0xdb80 kernel/bpf/core.c:1954
 __bpf_prog_run512+0xb5/0xe0 kernel/bpf/core.c:2195
 bpf_dispatcher_nop_func include/linux/bpf.h:1181 [inline]
 __bpf_prog_run include/linux/filter.h:609 [inline]
 bpf_prog_run include/linux/filter.h:616 [inline]
 bpf_test_run+0x474/0xaf0 net/bpf/test_run.c:423
 bpf_prog_test_run_skb+0x14e5/0x1f20 net/bpf/test_run.c:1045
 bpf_prog_test_run+0x6af/0xac0 kernel/bpf/syscall.c:3996
 __sys_bpf+0x649/0xd60 kernel/bpf/syscall.c:5353
 __do_sys_bpf kernel/bpf/syscall.c:5439 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5437 [inline]
 __ia32_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5437
 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: 6754 Comm: syz-executor.3 Not tainted 6.5.0-syzkaller-11704-g3f86ed6ec0b3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
=====================================================