syzbot

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BUG: KMSAN: uninit-value in __read_once_size include/linux/compiler.h:197 [inline]
BUG: KMSAN: uninit-value in compound_head include/linux/page-flags.h:142 [inline]
BUG: KMSAN: uninit-value in put_page include/linux/mm.h:859 [inline]
BUG: KMSAN: uninit-value in __skb_frag_unref include/linux/skbuff.h:2764 [inline]
BUG: KMSAN: uninit-value in skb_release_data+0x323/0x880 net/core/skbuff.c:565
CPU: 1 PID: 11196 Comm: syz-executor2 Not tainted 4.17.0+ #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+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:1125
 __msan_warning_32+0x70/0xc0 mm/kmsan/kmsan_instr.c:620
 __read_once_size include/linux/compiler.h:197 [inline]
 compound_head include/linux/page-flags.h:142 [inline]
 put_page include/linux/mm.h:859 [inline]
 __skb_frag_unref include/linux/skbuff.h:2764 [inline]
 skb_release_data+0x323/0x880 net/core/skbuff.c:565
 skb_release_all net/core/skbuff.c:628 [inline]
 __kfree_skb+0xab/0x280 net/core/skbuff.c:642
 sk_eat_skb include/net/sock.h:2300 [inline]
 tcp_recvmsg+0x2b50/0x40b0 net/ipv4/tcp.c:1987
 inet_recvmsg+0x4e3/0x610 net/ipv4/af_inet.c:830
 sock_recvmsg_nosec net/socket.c:802 [inline]
 sock_recvmsg net/socket.c:809 [inline]
 __sys_recvfrom+0x648/0x820 net/socket.c:1846
 __do_sys_recvfrom net/socket.c:1864 [inline]
 __se_sys_recvfrom net/socket.c:1860 [inline]
 __x64_sys_recvfrom+0x1a2/0x210 net/socket.c:1860
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x455a99
RSP: 002b:00007f188fa0fc68 EFLAGS: 00000246 ORIG_RAX: 000000000000002d
RAX: ffffffffffffffda RBX: 00007f188fa106d4 RCX: 0000000000455a99
RDX: 6478c8501c739c9d RSI: 0000000020f9cf9b RDI: 0000000000000014
RBP: 000000000072bf48 R08: 0000000000000000 R09: 0000000000000035
R10: 0000000000000120 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004c081a R14: 00000000004d03b0 R15: 0000000000000001

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:282 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:297 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:689
 kmsan_memcpy_origins+0x11d/0x170 mm/kmsan/kmsan.c:530
 __msan_memcpy+0x109/0x160 mm/kmsan/kmsan_instr.c:413
 skb_try_coalesce+0x151f/0x1c00 net/core/skbuff.c:4853
 tcp_try_coalesce net/ipv4/tcp_input.c:4274 [inline]
 tcp_queue_rcv+0x347/0x1200 net/ipv4/tcp_input.c:4516
 tcp_data_queue+0x1510/0xa3c0 net/ipv4/tcp_input.c:4608
 tcp_rcv_established+0x196e/0x2bb0 net/ipv4/tcp_input.c:5460
 tcp_v4_do_rcv+0x6d2/0xd90 net/ipv4/tcp_ipv4.c:1477
 sk_backlog_rcv include/net/sock.h:909 [inline]
 __release_sock+0x2dc/0x680 net/core/sock.c:2335
 __sk_flush_backlog+0x52/0x70 net/core/sock.c:2355
 sk_flush_backlog include/net/sock.h:996 [inline]
 tcp_sendmsg_locked+0xd07/0x6610 net/ipv4/tcp.c:1284
 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1447
 inet_sendmsg+0x3fc/0x760 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg net/socket.c:639 [inline]
 __sys_sendto+0x6c4/0x7e0 net/socket.c:1789
 __do_sys_sendto net/socket.c:1801 [inline]
 __se_sys_sendto net/socket.c:1797 [inline]
 __x64_sys_sendto+0x1a1/0x210 net/socket.c:1797
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:282 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:192
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:318
 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan.c:325
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2753 [inline]
 __kmalloc_node_track_caller+0xb35/0x11b0 mm/slub.c:4395
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cb/0x9e0 net/core/skbuff.c:206
 alloc_skb_fclone include/linux/skbuff.h:1030 [inline]
 sk_stream_alloc_skb+0x17c/0xcf0 net/ipv4/tcp.c:875
 tcp_sendmsg_locked+0x237e/0x6610 net/ipv4/tcp.c:1290
 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1447
 inet_sendmsg+0x3fc/0x760 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg net/socket.c:639 [inline]
 __sys_sendto+0x6c4/0x7e0 net/socket.c:1789
 __do_sys_sendto net/socket.c:1801 [inline]
 __se_sys_sendto net/socket.c:1797 [inline]
 __x64_sys_sendto+0x1a1/0x210 net/socket.c:1797
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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