KMSAN: uninit-value in __skb_checksum_complete (5)
From: syzbot
Date: Fri Aug 14 2020 - 11:09:23 EST
Hello,
syzbot found the following issue on:
HEAD commit: ce8056d1 wip: changed copy_from_user where instrumented
git tree: https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=149f894a900000
kernel config: https://syzkaller.appspot.com/x/.config?x=3afe005fb99591f
dashboard link: https://syzkaller.appspot.com/bug?extid=b024befb3ca7990fea37
compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)
Unfortunately, I don't have any reproducer for this issue yet.
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b024befb3ca7990fea37@xxxxxxxxxxxxxxxxxxxxxxxxx
=====================================================
BUG: KMSAN: uninit-value in __skb_checksum_complete+0x425/0x630 net/core/skbuff.c:2850
CPU: 1 PID: 8705 Comm: kworker/u4:2 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x21c/0x280 lib/dump_stack.c:118
kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
__msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
__skb_checksum_complete+0x425/0x630 net/core/skbuff.c:2850
nf_ip6_checksum+0x565/0x670 net/netfilter/utils.c:91
nf_nat_icmpv6_reply_translation+0x312/0x1360 net/netfilter/nf_nat_proto.c:800
nf_nat_ipv6_fn+0x3c4/0x570 net/netfilter/nf_nat_proto.c:873
nf_nat_ipv6_local_fn+0xaa/0x800 net/netfilter/nf_nat_proto.c:946
nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
nf_hook_slow+0x17b/0x460 net/netfilter/core.c:512
nf_hook include/linux/netfilter.h:262 [inline]
__ip6_local_out+0x696/0x7c0 net/ipv6/output_core.c:167
ip6_local_out+0xa1/0x1e0 net/ipv6/output_core.c:177
ip6_send_skb net/ipv6/ip6_output.c:1865 [inline]
ip6_push_pending_frames+0x252/0x5b0 net/ipv6/ip6_output.c:1885
icmpv6_push_pending_frames+0x6d1/0x710 net/ipv6/icmp.c:304
icmp6_send+0x3979/0x40e0 net/ipv6/icmp.c:617
icmpv6_send+0xdf/0x110 net/ipv6/ip6_icmp.c:43
ip6_pkt_drop+0x906/0xa00 net/ipv6/route.c:4406
ip6_pkt_discard_out+0xbb/0x130 net/ipv6/route.c:4419
dst_output include/net/dst.h:443 [inline]
ip6_local_out+0x17b/0x1e0 net/ipv6/output_core.c:179
ip6tunnel_xmit include/net/ip6_tunnel.h:160 [inline]
udp_tunnel6_xmit_skb+0x818/0xf80 net/ipv6/ip6_udp_tunnel.c:109
geneve6_xmit_skb drivers/net/geneve.c:973 [inline]
geneve_xmit+0x2b5d/0x3200 drivers/net/geneve.c:1002
__netdev_start_xmit include/linux/netdevice.h:4611 [inline]
netdev_start_xmit include/linux/netdevice.h:4625 [inline]
xmit_one+0x3cf/0x750 net/core/dev.c:3556
dev_hard_start_xmit net/core/dev.c:3572 [inline]
__dev_queue_xmit+0x3aad/0x4470 net/core/dev.c:4131
dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164
batadv_send_skb_packet+0x622/0x970 net/batman-adv/send.c:108
batadv_send_broadcast_skb+0x76/0x90 net/batman-adv/send.c:127
batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:393 [inline]
batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline]
batadv_iv_send_outstanding_bat_ogm_packet+0xb2e/0xef0 net/batman-adv/bat_iv_ogm.c:1710
process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
kthread+0x551/0x590 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293
Uninit was stored to memory at:
kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
kmsan_memcpy_memmove_metadata+0x272/0x2e0 mm/kmsan/kmsan.c:247
kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:267
__msan_memcpy+0x43/0x50 mm/kmsan/kmsan_instr.c:116
csum_partial_copy+0xae/0x100 lib/checksum.c:154
skb_copy_and_csum_bits+0x261/0x1360 net/core/skbuff.c:2737
icmpv6_getfrag+0x148/0x3b0 net/ipv6/icmp.c:319
__ip6_append_data+0x5a33/0x71b0 net/ipv6/ip6_output.c:1623
ip6_append_data+0x44b/0x6e0 net/ipv6/ip6_output.c:1757
icmp6_send+0x3711/0x40e0 net/ipv6/icmp.c:609
icmpv6_send+0xdf/0x110 net/ipv6/ip6_icmp.c:43
ip6_pkt_drop+0x906/0xa00 net/ipv6/route.c:4406
ip6_pkt_discard_out+0xbb/0x130 net/ipv6/route.c:4419
dst_output include/net/dst.h:443 [inline]
ip6_local_out+0x17b/0x1e0 net/ipv6/output_core.c:179
ip6tunnel_xmit include/net/ip6_tunnel.h:160 [inline]
udp_tunnel6_xmit_skb+0x818/0xf80 net/ipv6/ip6_udp_tunnel.c:109
geneve6_xmit_skb drivers/net/geneve.c:973 [inline]
geneve_xmit+0x2b5d/0x3200 drivers/net/geneve.c:1002
__netdev_start_xmit include/linux/netdevice.h:4611 [inline]
netdev_start_xmit include/linux/netdevice.h:4625 [inline]
xmit_one+0x3cf/0x750 net/core/dev.c:3556
dev_hard_start_xmit net/core/dev.c:3572 [inline]
__dev_queue_xmit+0x3aad/0x4470 net/core/dev.c:4131
dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164
batadv_send_skb_packet+0x622/0x970 net/batman-adv/send.c:108
batadv_send_broadcast_skb+0x76/0x90 net/batman-adv/send.c:127
batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:393 [inline]
batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline]
batadv_iv_send_outstanding_bat_ogm_packet+0xb2e/0xef0 net/batman-adv/bat_iv_ogm.c:1710
process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
kthread+0x551/0x590 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293
Uninit was stored to memory at:
kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
kmsan_memcpy_memmove_metadata+0x272/0x2e0 mm/kmsan/kmsan.c:247
kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:267
__msan_memcpy+0x43/0x50 mm/kmsan/kmsan_instr.c:116
pskb_expand_head+0x3fd/0x1e30 net/core/skbuff.c:1636
__skb_cow include/linux/skbuff.h:3145 [inline]
skb_cow_head include/linux/skbuff.h:3179 [inline]
geneve_build_skb+0x575/0xf90 drivers/net/geneve.c:754
geneve6_xmit_skb drivers/net/geneve.c:969 [inline]
geneve_xmit+0x286c/0x3200 drivers/net/geneve.c:1002
__netdev_start_xmit include/linux/netdevice.h:4611 [inline]
netdev_start_xmit include/linux/netdevice.h:4625 [inline]
xmit_one+0x3cf/0x750 net/core/dev.c:3556
dev_hard_start_xmit net/core/dev.c:3572 [inline]
__dev_queue_xmit+0x3aad/0x4470 net/core/dev.c:4131
dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164
batadv_send_skb_packet+0x622/0x970 net/batman-adv/send.c:108
batadv_send_broadcast_skb+0x76/0x90 net/batman-adv/send.c:127
batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:393 [inline]
batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline]
batadv_iv_send_outstanding_bat_ogm_packet+0xb2e/0xef0 net/batman-adv/bat_iv_ogm.c:1710
process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
kthread+0x551/0x590 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293
Uninit was stored to memory at:
kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
kmsan_memcpy_memmove_metadata+0x272/0x2e0 mm/kmsan/kmsan.c:247
kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:267
__msan_memcpy+0x43/0x50 mm/kmsan/kmsan_instr.c:116
pskb_expand_head+0x3fd/0x1e30 net/core/skbuff.c:1636
__skb_cow include/linux/skbuff.h:3145 [inline]
skb_cow_head include/linux/skbuff.h:3179 [inline]
batadv_skb_head_push+0x2cc/0x410 net/batman-adv/soft-interface.c:75
batadv_send_skb_packet+0x1ed/0x970 net/batman-adv/send.c:86
batadv_send_broadcast_skb+0x76/0x90 net/batman-adv/send.c:127
batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:393 [inline]
batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline]
batadv_iv_send_outstanding_bat_ogm_packet+0xb2e/0xef0 net/batman-adv/bat_iv_ogm.c:1710
process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
kthread+0x551/0x590 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293
Uninit was created at:
kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:144
kmsan_internal_alloc_meta_for_pages mm/kmsan/kmsan_shadow.c:269 [inline]
kmsan_alloc_page+0xc5/0x1a0 mm/kmsan/kmsan_shadow.c:293
__alloc_pages_nodemask+0xdf0/0x1030 mm/page_alloc.c:4889
__alloc_pages include/linux/gfp.h:509 [inline]
__alloc_pages_node include/linux/gfp.h:522 [inline]
alloc_pages_node include/linux/gfp.h:536 [inline]
__page_frag_cache_refill mm/page_alloc.c:4964 [inline]
page_frag_alloc+0x35b/0x880 mm/page_alloc.c:4994
__netdev_alloc_skb+0xc3d/0xc90 net/core/skbuff.c:456
__netdev_alloc_skb_ip_align include/linux/skbuff.h:2826 [inline]
netdev_alloc_skb_ip_align include/linux/skbuff.h:2836 [inline]
batadv_iv_ogm_aggregate_new net/batman-adv/bat_iv_ogm.c:558 [inline]
batadv_iv_ogm_queue_add+0x13bf/0x1c60 net/batman-adv/bat_iv_ogm.c:670
batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:849 [inline]
batadv_iv_ogm_schedule+0x126d/0x1660 net/batman-adv/bat_iv_ogm.c:869
batadv_iv_send_outstanding_bat_ogm_packet+0xd69/0xef0 net/batman-adv/bat_iv_ogm.c:1722
process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
kthread+0x551/0x590 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293
=====================================================
---
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