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BUG: KMSAN: uninit-value in __skb_dst_copy include/net/dst.h:279 [inline]
BUG: KMSAN: uninit-value in skb_dst_copy include/net/dst.h:285 [inline]
BUG: KMSAN: uninit-value in __copy_skb_header+0x2bf/0x720 net/core/skbuff.c:935
CPU: 1 PID: 6343 Comm: syz-executor.2 Not tainted 5.4.0-rc5+ #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+0x191/0x1f0 lib/dump_stack.c:113
 kmsan_report+0x128/0x220 mm/kmsan/kmsan_report.c:108
 __msan_warning+0x73/0xe0 mm/kmsan/kmsan_instr.c:245
 __skb_dst_copy include/net/dst.h:279 [inline]
 skb_dst_copy include/net/dst.h:285 [inline]
 __copy_skb_header+0x2bf/0x720 net/core/skbuff.c:935
 __skb_clone+0xa2/0x970 net/core/skbuff.c:987
 skb_clone+0x402/0x5d0 net/core/skbuff.c:1455
 dccp_v6_do_rcv+0x2df/0x11f0 net/dccp/ipv6.c:603
 sk_backlog_rcv include/net/sock.h:950 [inline]
 __release_sock+0x448/0x640 net/core/sock.c:2439
 release_sock+0x99/0x2a0 net/core/sock.c:2955
 dccp_sendmsg+0x1017/0x1270 net/dccp/proto.c:814
 inet_sendmsg+0x2d8/0x2e0 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg net/socket.c:657 [inline]
 ___sys_sendmsg+0x12c4/0x1590 net/socket.c:2311
 __sys_sendmmsg+0x53a/0xae0 net/socket.c:2413
 __do_sys_sendmmsg net/socket.c:2442 [inline]
 __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2439
 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2439
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x459f49
Code: ad b6 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 b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f4390463c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459f49
RDX: 04000000000000d0 RSI: 0000000020003d40 RDI: 0000000000000009
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f43904646d4
R13: 00000000004c7b88 R14: 00000000004ddc90 R15: 00000000ffffffff

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:151 [inline]
 kmsan_internal_poison_shadow+0x60/0x120 mm/kmsan/kmsan.c:134
 kmsan_slab_alloc+0xaa/0x120 mm/kmsan/kmsan_hooks.c:88
 slab_alloc_node mm/slub.c:2799 [inline]
 slab_alloc mm/slub.c:2808 [inline]
 kmem_cache_alloc+0x8d9/0xd20 mm/slub.c:2813
 skb_clone+0x326/0x5d0 net/core/skbuff.c:1448
 dccp_v6_do_rcv+0x2df/0x11f0 net/dccp/ipv6.c:603
 sk_backlog_rcv include/net/sock.h:950 [inline]
 __release_sock+0x448/0x640 net/core/sock.c:2439
 release_sock+0x99/0x2a0 net/core/sock.c:2955
 dccp_sendmsg+0x1017/0x1270 net/dccp/proto.c:814
 inet_sendmsg+0x2d8/0x2e0 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg net/socket.c:657 [inline]
 ___sys_sendmsg+0x12c4/0x1590 net/socket.c:2311
 __sys_sendmmsg+0x53a/0xae0 net/socket.c:2413
 __do_sys_sendmmsg net/socket.c:2442 [inline]
 __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2439
 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2439
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
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