================================================================== BUG: KMSAN: uninit-value in ip_check_mc_rcu+0x2a5/0x670 net/ipv4/igmp.c:2721 CPU: 0 PID: 16032 Comm: syz-executor.5 Not tainted 5.0.0-rc1+ #9 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+0x173/0x1d0 lib/dump_stack.c:113 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:600 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313 ip_check_mc_rcu+0x2a5/0x670 net/ipv4/igmp.c:2721 __mkroute_output net/ipv4/route.c:2213 [inline] ip_route_output_key_hash_rcu+0x1f91/0x3ba0 net/ipv4/route.c:2492 ip_route_output_key_hash net/ipv4/route.c:2321 [inline] __ip_route_output_key include/net/route.h:124 [inline] ip_route_output_flow+0x1ee/0x3e0 net/ipv4/route.c:2576 ip_route_output_key include/net/route.h:134 [inline] ip_tunnel_xmit+0x11fb/0x3980 net/ipv4/ip_tunnel.c:717 __gre_xmit net/ipv4/ip_gre.c:453 [inline] ipgre_xmit+0x1098/0x11c0 net/ipv4/ip_gre.c:710 __netdev_start_xmit include/linux/netdevice.h:4382 [inline] netdev_start_xmit include/linux/netdevice.h:4391 [inline] xmit_one net/core/dev.c:3278 [inline] dev_hard_start_xmit+0x604/0xc40 net/core/dev.c:3294 __dev_queue_xmit+0x2e48/0x3b80 net/core/dev.c:3864 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3897 packet_snd net/packet/af_packet.c:2932 [inline] packet_sendmsg+0x79bb/0x9760 net/packet/af_packet.c:2957 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116 __sys_sendmsg net/socket.c:2154 [inline] __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2161 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x457e39 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f5bfcc0fc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457e39 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000006 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5bfcc106d4 R13: 00000000004c53f6 R14: 00000000004d91c0 R15: 00000000ffffffff Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:205 [inline] kmsan_save_stack mm/kmsan/kmsan.c:220 [inline] kmsan_internal_chain_origin+0x134/0x230 mm/kmsan/kmsan.c:426 __msan_chain_origin+0x70/0xe0 mm/kmsan/kmsan_instr.c:200 ip_tunnel_init_flow include/net/ip_tunnels.h:248 [inline] ip_tunnel_xmit+0xb06/0x3980 net/ipv4/ip_tunnel.c:706 __gre_xmit net/ipv4/ip_gre.c:453 [inline] ipgre_xmit+0x1098/0x11c0 net/ipv4/ip_gre.c:710 __netdev_start_xmit include/linux/netdevice.h:4382 [inline] netdev_start_xmit include/linux/netdevice.h:4391 [inline] xmit_one net/core/dev.c:3278 [inline] dev_hard_start_xmit+0x604/0xc40 net/core/dev.c:3294 __dev_queue_xmit+0x2e48/0x3b80 net/core/dev.c:3864 netlink: 8 bytes leftover after parsing attributes in process `syz-executor.1'. dev_queue_xmit+0x4b/0x60 net/core/dev.c:3897 packet_snd net/packet/af_packet.c:2932 [inline] packet_sendmsg+0x79bb/0x9760 net/packet/af_packet.c:2957 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116 __sys_sendmsg net/socket.c:2154 [inline] __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2161 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:205 [inline] kmsan_save_stack mm/kmsan/kmsan.c:220 [inline] kmsan_internal_chain_origin+0x134/0x230 mm/kmsan/kmsan.c:426 kmsan_memcpy_memmove_metadata+0xcf2/0xf10 mm/kmsan/kmsan.c:304 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:324 __msan_memcpy+0x58/0x70 mm/kmsan/kmsan_instr.c:139 pskb_expand_head+0x34c/0x18f0 net/core/skbuff.c:1474 __skb_cow include/linux/skbuff.h:2973 [inline] skb_cow_head include/linux/skbuff.h:3007 [inline] ipgre_xmit+0x724/0x11c0 net/ipv4/ip_gre.c:689 protocol 88fb is buggy, dev hsr_slave_0 __netdev_start_xmit include/linux/netdevice.h:4382 [inline] netdev_start_xmit include/linux/netdevice.h:4391 [inline] xmit_one net/core/dev.c:3278 [inline] dev_hard_start_xmit+0x604/0xc40 net/core/dev.c:3294 __dev_queue_xmit+0x2e48/0x3b80 net/core/dev.c:3864 protocol 88fb is buggy, dev hsr_slave_1 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3897 packet_snd net/packet/af_packet.c:2932 [inline] packet_sendmsg+0x79bb/0x9760 net/packet/af_packet.c:2957 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116 __sys_sendmsg net/socket.c:2154 [inline] __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2161 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:205 [inline] kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:159 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:185 slab_post_alloc_hook mm/slab.h:446 [inline] slab_alloc_node mm/slub.c:2754 [inline] __kmalloc_node_track_caller+0xe9e/0xff0 mm/slub.c:4377 __kmalloc_reserve net/core/skbuff.c:140 [inline] __alloc_skb+0x309/0xa20 net/core/skbuff.c:208 alloc_skb include/linux/skbuff.h:1012 [inline] alloc_skb_with_frags+0x1c7/0xac0 net/core/skbuff.c:5288 sock_alloc_send_pskb+0xafd/0x10a0 net/core/sock.c:2091 packet_alloc_skb net/packet/af_packet.c:2783 [inline] packet_snd net/packet/af_packet.c:2876 [inline] packet_sendmsg+0x6881/0x9760 net/packet/af_packet.c:2957 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116 __sys_sendmsg net/socket.c:2154 [inline] __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2161 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 ==================================================================