================================================================== BUG: KMSAN: uninit-value in atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:106 [inline] BUG: KMSAN: uninit-value in queued_spin_lock include/asm-generic/qspinlock.h:87 [inline] BUG: KMSAN: uninit-value in do_raw_spin_lock+0x130/0x410 include/linux/spinlock.h:180 CPU: 1 PID: 3028 Comm: syz-executor3 Not tainted 4.20.0-rc3+ #106 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+0x32d/0x480 lib/dump_stack.c:113 kmsan_report+0x12d/0x290 mm/kmsan/kmsan.c:683 kmsan_internal_check_memory+0x32a/0xa50 mm/kmsan/kmsan.c:743 kmsan_check_memory+0xd/0x10 mm/kmsan/kmsan.c:776 atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:106 [inline] queued_spin_lock include/asm-generic/qspinlock.h:87 [inline] do_raw_spin_lock+0x130/0x410 include/linux/spinlock.h:180 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline] _raw_spin_lock_bh+0x60/0x70 kernel/locking/spinlock.c:168 spin_lock_bh include/linux/spinlock.h:334 [inline] __rhashtable_insert_fast include/linux/rhashtable.h:596 [inline] rhashtable_lookup_get_insert_key include/linux/rhashtable.h:867 [inline] inet_frag_create net/ipv4/inet_fragment.c:194 [inline] inet_frag_find+0x173a/0x2a70 net/ipv4/inet_fragment.c:217 ip_find net/ipv4/ip_fragment.c:283 [inline] ip_defrag+0x57c/0x6840 net/ipv4/ip_fragment.c:682 nf_ct_ipv4_gather_frags net/ipv4/netfilter/nf_defrag_ipv4.c:34 [inline] ipv4_conntrack_defrag+0x610/0x770 net/ipv4/netfilter/nf_defrag_ipv4.c:89 nf_hook_entry_hookfn include/linux/netfilter.h:119 [inline] nf_hook_slow+0x15c/0x3d0 net/netfilter/core.c:511 nf_hook include/linux/netfilter.h:244 [inline] __ip_local_out+0x6dc/0x800 net/ipv4/ip_output.c:113 ip_local_out+0xa4/0x1d0 net/ipv4/ip_output.c:122 iptunnel_xmit+0x812/0xd30 net/ipv4/ip_tunnel_core.c:91 ip_tunnel_xmit+0x3961/0x3da0 net/ipv4/ip_tunnel.c:787 __gre_xmit net/ipv4/ip_gre.c:451 [inline] ipgre_xmit+0xee6/0x1030 net/ipv4/ip_gre.c:705 __netdev_start_xmit include/linux/netdevice.h:4356 [inline] netdev_start_xmit include/linux/netdevice.h:4365 [inline] xmit_one net/core/dev.c:3252 [inline] dev_hard_start_xmit+0x6dc/0xde0 net/core/dev.c:3268 __dev_queue_xmit+0x2d9e/0x3e00 net/core/dev.c:3838 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3871 packet_snd net/packet/af_packet.c:2928 [inline] packet_sendmsg+0x84b3/0x9180 net/packet/af_packet.c:2953 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xdbc/0x11d0 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+0xcd/0x110 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x457569 Code: fd b3 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 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f3800e09c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000004 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3800e0a6d4 R13: 00000000004c3f7d R14: 00000000004d65d8 R15: 00000000ffffffff Uninit was created at: No stack Byte 0 of 8 is uninitialized Memory access of size 8 starts at ffff88806e3bec40 ==================================================================