=====================================================
BUG: KMSAN: uninit-value in ip_tunnel_xmit+0x54f/0x3da0 net/ipv4/ip_tunnel.c:658
 ip_tunnel_xmit+0x54f/0x3da0 net/ipv4/ip_tunnel.c:658
 __gre_xmit net/ipv4/ip_gre.c:469 [inline]
 ipgre_xmit+0x1242/0x12b0 net/ipv4/ip_gre.c:657
 __netdev_start_xmit include/linux/netdevice.h:4775 [inline]
 netdev_start_xmit include/linux/netdevice.h:4789 [inline]
 xmit_one+0x2e3/0x830 net/core/dev.c:3532
 dev_hard_start_xmit+0x185/0x410 net/core/dev.c:3548
 __dev_queue_xmit+0x21f5/0x3470 net/core/dev.c:4176
 dev_queue_xmit+0x4f/0x60 net/core/dev.c:4209
 __bpf_tx_skb net/core/filter.c:2113 [inline]
 __bpf_redirect_no_mac net/core/filter.c:2138 [inline]
 __bpf_redirect+0x1122/0x1a80 net/core/filter.c:2161
 ____bpf_clone_redirect net/core/filter.c:2428 [inline]
 bpf_clone_redirect+0x4a6/0x670 net/core/filter.c:2400
 ___bpf_prog_run+0x93a/0xb300 kernel/bpf/core.c:1835
 __bpf_prog_run512+0x125/0x190 kernel/bpf/core.c:2075
 bpf_dispatcher_nop_func include/linux/bpf.h:804 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 bpf_test_run+0x787/0x1080 net/bpf/test_run.c:402
 bpf_prog_test_run_skb+0x1769/0x21c0 net/bpf/test_run.c:1111
 bpf_prog_test_run+0x788/0x820 kernel/bpf/syscall.c:3369
 __sys_bpf+0x9ca/0x10b0 kernel/bpf/syscall.c:4681
 __do_sys_bpf kernel/bpf/syscall.c:4767 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4765 [inline]
 __ia32_sys_bpf+0xe5/0x130 kernel/bpf/syscall.c:4765
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x95/0xf0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:754 [inline]
 slab_alloc_node mm/slub.c:3231 [inline]
 __kmalloc_node_track_caller+0xdee/0x14e0 mm/slub.c:4962
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 pskb_expand_head+0x271/0x1fc0 net/core/skbuff.c:1700
 skb_ensure_writable+0x505/0x5b0 net/core/skbuff.c:5614
 __bpf_try_make_writable net/core/filter.c:1654 [inline]
 bpf_try_make_writable net/core/filter.c:1660 [inline]
 bpf_try_make_head_writable net/core/filter.c:1668 [inline]
 ____bpf_clone_redirect net/core/filter.c:2422 [inline]
 bpf_clone_redirect+0x25e/0x670 net/core/filter.c:2400
 ___bpf_prog_run+0x93a/0xb300 kernel/bpf/core.c:1835
 __bpf_prog_run512+0x125/0x190 kernel/bpf/core.c:2075
 bpf_dispatcher_nop_func include/linux/bpf.h:804 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 bpf_test_run+0x787/0x1080 net/bpf/test_run.c:402
 bpf_prog_test_run_skb+0x1769/0x21c0 net/bpf/test_run.c:1111
 bpf_prog_test_run+0x788/0x820 kernel/bpf/syscall.c:3369
 __sys_bpf+0x9ca/0x10b0 kernel/bpf/syscall.c:4681
 __do_sys_bpf kernel/bpf/syscall.c:4767 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4765 [inline]
 __ia32_sys_bpf+0xe5/0x130 kernel/bpf/syscall.c:4765
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x95/0xf0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

CPU: 1 PID: 14236 Comm: syz-executor.2 Not tainted 5.18.0-syzkaller-16253-g2f3064574275 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
=====================================================