===================================================== BUG: KMSAN: uninit-value in update_stack_state+0x974/0xb40 arch/x86/kernel/unwind_frame.c:238 CPU: 0 PID: 16265 Comm: syz-executor.4 Not tainted 5.8.0-rc5-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+0x1df/0x240 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 update_stack_state+0x974/0xb40 arch/x86/kernel/unwind_frame.c:238 unwind_next_frame+0x8c6/0xed0 arch/x86/kernel/unwind_frame.c:305 arch_stack_walk+0x33e/0x3e0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x117/0x1a0 kernel/stacktrace.c:123 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline] kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310 kmsan_memcpy_memmove_metadata+0x272/0x2e0 mm/kmsan/kmsan.c:247 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:267 __msan_memcpy+0x43/0x50 mm/kmsan/kmsan_instr.c:116 pskb_expand_head+0x38b/0x1b00 net/core/skbuff.c:1636 skb_unclone include/linux/skbuff.h:1622 [inline] skb_copy_ubufs+0x2a0/0x2190 net/core/skbuff.c:1348 skb_orphan_frags_rx include/linux/skbuff.h:2764 [inline] __netif_receive_skb_core+0x548b/0x5890 net/core/dev.c:5246 __netif_receive_skb_one_core net/core/dev.c:5279 [inline] __netif_receive_skb net/core/dev.c:5395 [inline] process_backlog+0x605/0x14e0 net/core/dev.c:6239 napi_poll net/core/dev.c:6684 [inline] net_rx_action+0x746/0x1aa0 net/core/dev.c:6752 __do_softirq+0x311/0x83d kernel/softirq.c:293 asm_call_on_stack+0x12/0x20 arch/x86/entry/entry_64.S:711 __run_on_irqstack arch/x86/include/asm/irq_stack.h:23 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline] do_softirq_own_stack+0x7c/0xa0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:390 [inline] __irq_exit_rcu+0x226/0x270 kernel/softirq.c:420 irq_exit_rcu+0xe/0x10 kernel/softirq.c:432 sysvec_call_function_single+0x107/0x130 arch/x86/kernel/smp.c:243 asm_sysvec_call_function_single+0x12/0x20 arch/x86/include/asm/idtentry.h:601 RIP: 0010:__msan_poison_alloca+0xe3/0x120 mm/kmsan/kmsan_instr.c:191 Code: 00 e8 11 c8 d0 02 65 44 0f c1 3d 48 e2 31 5b 41 ff cf 75 34 89 c3 e8 bc 6d 2e ff 48 8b 44 24 08 48 89 44 24 10 ff 74 24 10 9d <4c> 89 e7 44 89 f6 89 da e8 10 f5 ff ff 48 8d 65 d8 5b 41 5c 41 5d RSP: 0018:ffffa399c3b82f00 EFLAGS: 00000246 RAX: 0000000000000246 RBX: 00000000050b013a RCX: ffffffffa4186530 RDX: 0000000000000a20 RSI: 0000000000060ad2 RDI: 00000000fac79b1a RBP: ffffa399c3b82f80 R08: 0000000000000002 R09: ffffa399c3b82f38 R10: 0000000000000004 R11: 0000000000000000 R12: ffffa399c3b82fa0 R13: 0000000000000001 R14: 0000000000000008 R15: 0000000000000000 native_save_fl kernel/softirq.c:330 [inline] arch_local_save_flags arch/x86/include/asm/irqflags.h:79 [inline] arch_local_irq_save arch/x86/include/asm/irqflags.h:120 [inline] do_softirq+0x50/0x150 kernel/softirq.c:333 netif_rx_ni+0x202/0x3b0 net/core/dev.c:4830 dev_loopback_xmit+0x58a/0x630 net/core/dev.c:3846 NF_HOOK include/linux/netfilter.h:307 [inline] ip6_finish_output2+0x2339/0x2620 net/ipv6/ip6_output.c:81 __ip6_finish_output+0x824/0x8e0 net/ipv6/ip6_output.c:143 ip6_finish_output+0x166/0x410 net/ipv6/ip6_output.c:153 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x60a/0x770 net/ipv6/ip6_output.c:176 dst_output include/net/dst.h:443 [inline] ip6_local_out+0x164/0x1d0 net/ipv6/output_core.c:179 ip6_send_skb+0xfa/0x390 net/ipv6/ip6_output.c:1865 udp_v6_send_skb+0x1834/0x1e80 net/ipv6/udp.c:1175 udpv6_sendmsg+0x4570/0x4940 net/ipv6/udp.c:1473 inet6_sendmsg+0x276/0x2e0 net/ipv6/af_inet6.c:638 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0xca5/0x1400 net/socket.c:2352 ___sys_sendmsg net/socket.c:2406 [inline] __sys_sendmmsg+0x876/0xd80 net/socket.c:2489 __compat_sys_sendmmsg net/compat.c:480 [inline] __do_compat_sys_sendmmsg net/compat.c:487 [inline] __se_compat_sys_sendmmsg+0xcd/0xf0 net/compat.c:484 __ia32_compat_sys_sendmmsg+0x56/0x70 net/compat.c:484 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2aa/0x400 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7fc5549 Code: Bad RIP value. RSP: 002b:00000000f5d7e0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000159 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020004d80 RDX: 0000000000000132 RSI: 0000000004000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Local variable ----ad@selinux_ip_postroute created at: selinux_ip_postroute+0xe2/0x1c90 security/selinux/hooks.c:5691 selinux_ip_postroute+0xe2/0x1c90 security/selinux/hooks.c:5691 =====================================================