syzbot

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BUG: KMSAN: uninit-value in __write_once_size include/linux/compiler.h:223 [inline]
BUG: KMSAN: uninit-value in atomic_set arch/x86/include/asm/atomic.h:43 [inline]
BUG: KMSAN: uninit-value in __build_skb net/core/skbuff.c:301 [inline]
BUG: KMSAN: uninit-value in __napi_alloc_skb+0x99d/0xa10 net/core/skbuff.c:483
CPU: 0 PID: 11846 Comm: blkid Not tainted 4.17.0+ #7
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __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:1121
 __msan_warning_32+0x70/0xc0 mm/kmsan/kmsan_instr.c:620
 __write_once_size include/linux/compiler.h:223 [inline]
 atomic_set arch/x86/include/asm/atomic.h:43 [inline]
 __build_skb net/core/skbuff.c:301 [inline]
 __napi_alloc_skb+0x99d/0xa10 net/core/skbuff.c:483
 napi_alloc_skb include/linux/skbuff.h:2655 [inline]
 page_to_skb+0x141/0x1190 drivers/net/virtio_net.c:349
 receive_mergeable drivers/net/virtio_net.c:812 [inline]
 receive_buf+0xc98/0x6ae0 drivers/net/virtio_net.c:917
 virtnet_receive drivers/net/virtio_net.c:1200 [inline]
 virtnet_poll+0x8ff/0x1420 drivers/net/virtio_net.c:1282
 napi_poll net/core/dev.c:5735 [inline]
 net_rx_action+0x766/0x1a80 net/core/dev.c:5801
 __do_softirq+0x592/0x979 kernel/softirq.c:285
 invoke_softirq kernel/softirq.c:365 [inline]
 irq_exit+0x202/0x240 kernel/softirq.c:405
 exiting_irq+0xe/0x10 arch/x86/include/asm/apic.h:525
 smp_apic_timer_interrupt+0x64/0x90 arch/x86/kernel/apic/apic.c:1055
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
 </IRQ>
RIP: 0010:kmsan_write_aligned_origin_inline mm/kmsan/kmsan_instr.c:505 [inline]
RIP: 0010:kmsan_set_origin_inline+0x7e/0x120 mm/kmsan/kmsan_instr.c:535
RSP: 0000:ffff8801c3dbf7d8 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
RAX: ffff88019b7df9a0 RBX: 0000000000000001 RCX: 000000019b7df9a0
RDX: 00000000001c3dbf RSI: 0000000000000000 RDI: ffff8801c3dbf9a0
RBP: ffff8801c3dbf800 R08: 0000000001080020 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004
R13: 000000009260006d R14: ffff8801c3dbf9a0 R15: 0000000000000001
 __msan_poison_alloca+0x15c/0x1d0 mm/kmsan/kmsan_instr.c:590
 __alloc_pages_nodemask+0xa3/0x5cc0 mm/page_alloc.c:4357
 alloc_pages_vma+0xcc6/0x17f0 mm/mempolicy.c:2057
 alloc_zeroed_user_highpage_movable include/linux/highmem.h:187 [inline]
 do_anonymous_page mm/memory.c:3157 [inline]
 handle_pte_fault mm/memory.c:3963 [inline]
 __handle_mm_fault mm/memory.c:4089 [inline]
 handle_mm_fault+0x41ec/0x7ed0 mm/memory.c:4126
 __do_page_fault+0xec6/0x1a10 arch/x86/mm/fault.c:1400
 do_page_fault+0xb7/0x250 arch/x86/mm/fault.c:1477
 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1160
RIP: 0033:0x7f8793b3d2b7
RSP: 002b:00007ffd98a2efd0 EFLAGS: 00010246
RAX: 0000000000000008 RBX: 00007f8793d4f000 RCX: 0000000000000040
RDX: 0000000000000001 RSI: 0000000000000073 RDI: fffffffffffff000
RBP: 00007ffd98a2f2c0 R08: 756e696c2d34365f R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd98a2f3a8
R13: 0000000000000002 R14: 00007ffd98a2f488 R15: 0000000000000001

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:294 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:685
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:464
 page_frag_alloc+0x22d/0x9a0 mm/page_alloc.c:4553
 __napi_alloc_skb+0x199/0xa10 net/core/skbuff.c:479
 napi_alloc_skb include/linux/skbuff.h:2655 [inline]
 page_to_skb+0x141/0x1190 drivers/net/virtio_net.c:349
 receive_mergeable drivers/net/virtio_net.c:812 [inline]
 receive_buf+0xc98/0x6ae0 drivers/net/virtio_net.c:917
 virtnet_receive drivers/net/virtio_net.c:1200 [inline]
 virtnet_poll+0x8ff/0x1420 drivers/net/virtio_net.c:1282
 napi_poll net/core/dev.c:5735 [inline]
 net_rx_action+0x766/0x1a80 net/core/dev.c:5801
 __do_softirq+0x592/0x979 kernel/softirq.c:285
Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:294 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:685
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:464
 page_frag_alloc+0x22d/0x9a0 mm/page_alloc.c:4553
 __napi_alloc_skb+0x199/0xa10 net/core/skbuff.c:479
 napi_alloc_skb include/linux/skbuff.h:2655 [inline]
 page_to_skb+0x141/0x1190 drivers/net/virtio_net.c:349
 receive_mergeable drivers/net/virtio_net.c:812 [inline]
 receive_buf+0xc98/0x6ae0 drivers/net/virtio_net.c:917
 virtnet_receive drivers/net/virtio_net.c:1200 [inline]
 virtnet_poll+0x8ff/0x1420 drivers/net/virtio_net.c:1282
 napi_poll net/core/dev.c:5735 [inline]
 net_rx_action+0x766/0x1a80 net/core/dev.c:5801
 __do_softirq+0x592/0x979 kernel/softirq.c:285
Local variable description: ----list@net_rx_action
Variable was created at:
 net_rx_action+0x6e/0x1a80 net/core/dev.c:5779
 __do_softirq+0x592/0x979 kernel/softirq.c:285
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