===================================================== BUG: KMSAN: uninit-value in ip6_parse_tlv+0xa4e/0xf80 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/ipv6/exthdrs.c:169 CPU: 0 PID: 10 Comm: ksoftirqd/0 Not tainted 5.10.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack syzkaller/managers/upstream-kmsan-gce-386/kernel/lib/dump_stack.c:77 [inline] dump_stack+0x21c/0x280 syzkaller/managers/upstream-kmsan-gce-386/kernel/lib/dump_stack.c:118 kmsan_report+0xfb/0x1e0 syzkaller/managers/upstream-kmsan-gce-386/kernel/mm/kmsan/kmsan_report.c:118 __msan_warning+0x5f/0xa0 syzkaller/managers/upstream-kmsan-gce-386/kernel/mm/kmsan/kmsan_instr.c:197 ip6_parse_tlv+0xa4e/0xf80 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/ipv6/exthdrs.c:169 ipv6_destopt_rcv+0x630/0xe80 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/ipv6/exthdrs.c:308 ip6_protocol_deliver_rcu+0x1402/0x25e0 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/ipv6/ip6_input.c:433 ip6_input_finish syzkaller/managers/upstream-kmsan-gce-386/kernel/net/ipv6/ip6_input.c:474 [inline] NF_HOOK syzkaller/managers/upstream-kmsan-gce-386/kernel/./include/linux/netfilter.h:301 [inline] ip6_input+0x12b/0x390 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/ipv6/ip6_input.c:483 ip6_mc_input+0xc77/0x12f0 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/ipv6/ip6_input.c:577 dst_input syzkaller/managers/upstream-kmsan-gce-386/kernel/./include/net/dst.h:449 [inline] ip6_rcv_finish+0x5fc/0x7f0 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/ipv6/ip6_input.c:76 NF_HOOK syzkaller/managers/upstream-kmsan-gce-386/kernel/./include/linux/netfilter.h:301 [inline] ipv6_rcv+0x1d1/0x460 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/ipv6/ip6_input.c:307 __netif_receive_skb_one_core syzkaller/managers/upstream-kmsan-gce-386/kernel/net/core/dev.c:5315 [inline] __netif_receive_skb+0x1ec/0x640 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/core/dev.c:5429 process_backlog+0x517/0xbd0 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/core/dev.c:6319 napi_poll+0x40a/0x1020 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/core/dev.c:6763 net_rx_action+0x34c/0xd30 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/core/dev.c:6833 __do_softirq+0x1a9/0x6fa syzkaller/managers/upstream-kmsan-gce-386/kernel/kernel/softirq.c:298 run_ksoftirqd+0x20/0x40 syzkaller/managers/upstream-kmsan-gce-386/kernel/kernel/softirq.c:653 smpboot_thread_fn+0x5f5/0xa90 syzkaller/managers/upstream-kmsan-gce-386/kernel/kernel/smpboot.c:165 kthread+0x51c/0x560 syzkaller/managers/upstream-kmsan-gce-386/kernel/kernel/kthread.c:292 ret_from_fork+0x1f/0x30 syzkaller/managers/upstream-kmsan-gce-386/kernel/arch/x86/entry/entry_64.S:296 Uninit was created at: kmsan_save_stack_with_flags syzkaller/managers/upstream-kmsan-gce-386/kernel/mm/kmsan/kmsan.c:121 [inline] kmsan_internal_poison_shadow+0x5c/0xf0 syzkaller/managers/upstream-kmsan-gce-386/kernel/mm/kmsan/kmsan.c:104 kmsan_slab_alloc+0x8d/0xe0 syzkaller/managers/upstream-kmsan-gce-386/kernel/mm/kmsan/kmsan_hooks.c:76 slab_alloc_node syzkaller/managers/upstream-kmsan-gce-386/kernel/mm/slub.c:2906 [inline] __kmalloc_node_track_caller+0xa48/0x1610 syzkaller/managers/upstream-kmsan-gce-386/kernel/mm/slub.c:4512 __kmalloc_reserve syzkaller/managers/upstream-kmsan-gce-386/kernel/net/core/skbuff.c:142 [inline] __alloc_skb+0x318/0xb00 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/core/skbuff.c:210 alloc_skb syzkaller/managers/upstream-kmsan-gce-386/kernel/./include/linux/skbuff.h:1094 [inline] alloc_skb_with_frags+0x1f3/0xc10 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/core/skbuff.c:5832 sock_alloc_send_pskb+0xcc4/0xe80 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/core/sock.c:2329 sock_alloc_send_skb+0xca/0xe0 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/core/sock.c:2346 __ip6_append_data+0x553e/0x7260 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/ipv6/ip6_output.c:1581 ip6_append_data+0x44b/0x6e0 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/ipv6/ip6_output.c:1757 rawv6_sendmsg+0x2aea/0x46a0 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/ipv6/raw.c:949 inet_sendmsg+0x15b/0x1d0 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/ipv4/af_inet.c:817 sock_sendmsg_nosec syzkaller/managers/upstream-kmsan-gce-386/kernel/net/socket.c:651 [inline] sock_sendmsg syzkaller/managers/upstream-kmsan-gce-386/kernel/net/socket.c:671 [inline] ____sys_sendmsg+0xcfc/0x12f0 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/socket.c:2353 ___sys_sendmsg syzkaller/managers/upstream-kmsan-gce-386/kernel/net/socket.c:2407 [inline] __sys_sendmmsg+0x882/0x1070 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/socket.c:2490 __compat_sys_sendmmsg syzkaller/managers/upstream-kmsan-gce-386/kernel/net/compat.c:361 [inline] __do_compat_sys_sendmmsg syzkaller/managers/upstream-kmsan-gce-386/kernel/net/compat.c:368 [inline] __se_compat_sys_sendmmsg+0xcd/0xf0 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/compat.c:365 __ia32_compat_sys_sendmmsg+0x56/0x70 syzkaller/managers/upstream-kmsan-gce-386/kernel/net/compat.c:365 do_syscall_32_irqs_on syzkaller/managers/upstream-kmsan-gce-386/kernel/arch/x86/entry/common.c:80 [inline] __do_fast_syscall_32+0x102/0x160 syzkaller/managers/upstream-kmsan-gce-386/kernel/arch/x86/entry/common.c:139 do_fast_syscall_32+0x6a/0xc0 syzkaller/managers/upstream-kmsan-gce-386/kernel/arch/x86/entry/common.c:162 do_SYSENTER_32+0x73/0x90 syzkaller/managers/upstream-kmsan-gce-386/kernel/arch/x86/entry/common.c:205 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c =====================================================