===================================================== BUG: KMSAN: uninit-value in ip_tunnel_xmit+0x585/0x3a40 net/ipv4/ip_tunnel.c:663 CPU: 0 PID: 11381 Comm: syz-executor.0 Not tainted 5.9.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x21c/0x280 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:122 __msan_warning+0x5f/0xa0 mm/kmsan/kmsan_instr.c:201 ip_tunnel_xmit+0x585/0x3a40 net/ipv4/ip_tunnel.c:663 __gre_xmit net/ipv4/ip_gre.c:466 [inline] ipgre_xmit+0x1261/0x1380 net/ipv4/ip_gre.c:650 __netdev_start_xmit include/linux/netdevice.h:4636 [inline] netdev_start_xmit include/linux/netdevice.h:4650 [inline] xmit_one+0x1fc/0x760 net/core/dev.c:3561 dev_hard_start_xmit net/core/dev.c:3577 [inline] __dev_queue_xmit+0x3310/0x4490 net/core/dev.c:4136 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4169 __bpf_tx_skb net/core/filter.c:2112 [inline] __bpf_redirect_no_mac net/core/filter.c:2137 [inline] __bpf_redirect+0x889/0x1690 net/core/filter.c:2160 ____bpf_clone_redirect net/core/filter.c:2191 [inline] bpf_clone_redirect+0x498/0x650 net/core/filter.c:2163 ___bpf_prog_run+0x4256/0x93c0 kernel/bpf/core.c:1516 __bpf_prog_run512+0x12e/0x190 kernel/bpf/core.c:1694 bpf_test_run+0x557/0xe30 include/linux/filter.h:734 bpf_prog_test_run_skb+0x17d7/0x3450 net/bpf/test_run.c:496 bpf_prog_test_run kernel/bpf/syscall.c:2996 [inline] __do_sys_bpf+0xb79a/0x1a8a0 kernel/bpf/syscall.c:4196 __se_sys_bpf+0x8e/0xa0 kernel/bpf/syscall.c:4136 __ia32_sys_bpf+0x4a/0x70 kernel/bpf/syscall.c:4136 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline] __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7f12549 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f54ca0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000165 RAX: ffffffffffffffda RBX: 000000000000000a RCX: 0000000020000780 RDX: 0000000000000048 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:129 [inline] kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:112 kmsan_slab_alloc+0x8d/0xe0 mm/kmsan/kmsan_hooks.c:80 slab_alloc_node mm/slub.c:2903 [inline] __kmalloc_node_track_caller+0x7de/0x1320 mm/slub.c:4507 __kmalloc_reserve net/core/skbuff.c:142 [inline] pskb_expand_head+0x25f/0x1df0 net/core/skbuff.c:1629 __skb_cow include/linux/skbuff.h:3160 [inline] skb_cow_head include/linux/skbuff.h:3194 [inline] ipgre_xmit+0x84b/0x1380 net/ipv4/ip_gre.c:629 __netdev_start_xmit include/linux/netdevice.h:4636 [inline] netdev_start_xmit include/linux/netdevice.h:4650 [inline] xmit_one+0x1fc/0x760 net/core/dev.c:3561 dev_hard_start_xmit net/core/dev.c:3577 [inline] __dev_queue_xmit+0x3310/0x4490 net/core/dev.c:4136 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4169 __bpf_tx_skb net/core/filter.c:2112 [inline] __bpf_redirect_no_mac net/core/filter.c:2137 [inline] __bpf_redirect+0x889/0x1690 net/core/filter.c:2160 ____bpf_clone_redirect net/core/filter.c:2191 [inline] bpf_clone_redirect+0x498/0x650 net/core/filter.c:2163 ___bpf_prog_run+0x4256/0x93c0 kernel/bpf/core.c:1516 __bpf_prog_run512+0x12e/0x190 kernel/bpf/core.c:1694 bpf_test_run+0x557/0xe30 include/linux/filter.h:734 bpf_prog_test_run_skb+0x17d7/0x3450 net/bpf/test_run.c:496 bpf_prog_test_run kernel/bpf/syscall.c:2996 [inline] __do_sys_bpf+0xb79a/0x1a8a0 kernel/bpf/syscall.c:4196 __se_sys_bpf+0x8e/0xa0 kernel/bpf/syscall.c:4136 __ia32_sys_bpf+0x4a/0x70 kernel/bpf/syscall.c:4136 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline] __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c =====================================================