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KASAN: use-after-free Write in nf_nat_setup_info

Status: auto-obsoleted due to no activity on 2024/05/12 18:38
Reported-by: syzbot+c55eec9136c0d848b161@syzkaller.appspotmail.com
First crash: 575d, last: 575d
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 KASAN: use-after-free Write in nf_nat_setup_info (2) 24 5 282d 306d 0/3 auto-obsoleted due to no activity on 2025/03/01 06:16
upstream KASAN: use-after-free Write in nf_nat_setup_info netfilter 24 1 941d 941d 0/29 auto-obsoleted due to no activity on 2023/05/10 12:28
upstream KMSAN: uninit-value in nf_nat_setup_info (2) netfilter 7 C 764 1251d 1331d 0/29 auto-obsoleted due to no activity on 2022/09/28 07:28

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in hlist_add_head_rcu include/linux/rculist.h:593 [inline]
BUG: KASAN: use-after-free in nf_nat_setup_info+0x1778/0x2188 net/netfilter/nf_nat_core.c:633
Write of size 8 at addr ffff0000cef114d8 by task syz-executor.3/15037

CPU: 0 PID: 15037 Comm: syz-executor.3 Not tainted 6.1.76-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x174/0x4c0 mm/kasan/report.c:395
 kasan_report+0xd4/0x130 mm/kasan/report.c:495
 __asan_report_store8_noabort+0x2c/0x38 mm/kasan/report_generic.c:356
 hlist_add_head_rcu include/linux/rculist.h:593 [inline]
 nf_nat_setup_info+0x1778/0x2188 net/netfilter/nf_nat_core.c:633
 __nf_nat_alloc_null_binding net/netfilter/nf_nat_core.c:664 [inline]
 nf_nat_alloc_null_binding net/netfilter/nf_nat_core.c:670 [inline]
 nf_nat_inet_fn+0x80c/0xad4 net/netfilter/nf_nat_core.c:759
 nf_nat_ipv4_fn net/netfilter/nf_nat_proto.c:645 [inline]
 nf_nat_ipv4_local_in+0x1bc/0x4bc net/netfilter/nf_nat_proto.c:708
 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
 nf_hook_slow+0xc8/0x1f4 net/netfilter/core.c:614
 nf_hook include/linux/netfilter.h:257 [inline]
 NF_HOOK+0x22c/0x3d4 include/linux/netfilter.h:300
 ip_local_deliver+0x11c/0x190 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:454 [inline]
 ip_rcv_finish+0x224/0x250 net/ipv4/ip_input.c:449
 NF_HOOK+0x328/0x3d4 include/linux/netfilter.h:302
 ip_rcv+0x78/0x98 net/ipv4/ip_input.c:569
 __netif_receive_skb_one_core net/core/dev.c:5528 [inline]
 __netif_receive_skb+0x18c/0x400 net/core/dev.c:5642
 process_backlog+0x410/0x784 net/core/dev.c:5970
 __napi_poll+0xb4/0x3f0 net/core/dev.c:6537
 napi_poll net/core/dev.c:6604 [inline]
 net_rx_action+0x5cc/0xd3c net/core/dev.c:6715
 __do_softirq+0x314/0xe38 kernel/softirq.c:571
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:79
 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:893
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:84
 do_softirq+0xf8/0x1ac kernel/softirq.c:472
 __local_bh_enable_ip+0x298/0x470 kernel/softirq.c:396
 local_bh_enable+0x28/0x34 include/linux/bottom_half.h:33
 rcu_read_unlock_bh include/linux/rcupdate.h:829 [inline]
 __dev_queue_xmit+0x1a68/0x38d8 net/core/dev.c:4320
 dev_queue_xmit include/linux/netdevice.h:3021 [inline]
 neigh_hh_output include/net/neighbour.h:528 [inline]
 neigh_output include/net/neighbour.h:542 [inline]
 ip_finish_output2+0xc58/0x1198 net/ipv4/ip_output.c:228
 __ip_finish_output+0x1b0/0x458
 ip_finish_output+0x40/0x268 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:291 [inline]
 ip_output+0x330/0x49c net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:444 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0xd8c/0x1840 net/ipv4/ip_output.c:532
 ip_queue_xmit+0x5c/0x78 net/ipv4/ip_output.c:546
 __tcp_transmit_skb+0x1954/0x3258 net/ipv4/tcp_output.c:1403
 tcp_transmit_skb net/ipv4/tcp_output.c:1421 [inline]
 tcp_write_xmit+0x131c/0x4e2c net/ipv4/tcp_output.c:2709
 __tcp_push_pending_frames+0x98/0x228 net/ipv4/tcp_output.c:2894
 tcp_push+0x44c/0x68c net/ipv4/tcp.c:733
 tcp_sendmsg_locked+0x2ca8/0x34f8 net/ipv4/tcp.c:1461
 tcp_sendmsg+0x40/0x64 net/ipv4/tcp.c:1489
 inet_sendmsg+0x15c/0x290 net/ipv4/af_inet.c:839
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x55c/0x848 net/socket.c:2514
 ___sys_sendmsg net/socket.c:2568 [inline]
 __sys_sendmmsg+0x318/0x7d8 net/socket.c:2654
 __do_sys_sendmmsg net/socket.c:2683 [inline]
 __se_sys_sendmmsg net/socket.c:2680 [inline]
 __arm64_sys_sendmmsg+0xa0/0xbc net/socket.c:2680
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Allocated by task 15037:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:52
 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0xac/0xc4 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 kmalloc_trace+0x7c/0x94 mm/slab_common.c:1050
 kmalloc include/linux/slab.h:553 [inline]
 kzalloc include/linux/slab.h:689 [inline]
 nf_ct_tmpl_alloc+0x90/0x1f4 net/netfilter/nf_conntrack_core.c:550
 nft_ct_set_zone_eval+0x3c8/0x600 net/netfilter/nft_ct.c:270
 expr_call_ops_eval net/netfilter/nf_tables_core.c:214 [inline]
 nft_do_chain+0x440/0x1544 net/netfilter/nf_tables_core.c:264
 nft_do_chain_ipv4+0x1a4/0x2d8 net/netfilter/nft_chain_filter.c:23
 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
 nf_hook_slow+0xc8/0x1f4 net/netfilter/core.c:614
 nf_hook include/linux/netfilter.h:257 [inline]
 NF_HOOK+0x22c/0x3d4 include/linux/netfilter.h:300
 ip_rcv+0x78/0x98 net/ipv4/ip_input.c:569
 __netif_receive_skb_one_core net/core/dev.c:5528 [inline]
 __netif_receive_skb+0x18c/0x400 net/core/dev.c:5642
 process_backlog+0x410/0x784 net/core/dev.c:5970
 __napi_poll+0xb4/0x3f0 net/core/dev.c:6537
 napi_poll net/core/dev.c:6604 [inline]
 net_rx_action+0x5cc/0xd3c net/core/dev.c:6715
 __do_softirq+0x314/0xe38 kernel/softirq.c:571

Freed by task 15037:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:52
 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516
 ____kasan_slab_free+0x144/0x1c0 mm/kasan/common.c:236
 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:244
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 __kmem_cache_free+0x2c0/0x4b4 mm/slub.c:3674
 kfree+0xcc/0x1b8 mm/slab_common.c:1007
 nf_ct_tmpl_free net/netfilter/nf_conntrack_core.c:571 [inline]
 nf_ct_destroy+0x198/0x298 net/netfilter/nf_conntrack_core.c:593
 nf_conntrack_destroy+0x124/0x2c8 net/netfilter/core.c:703
 nf_conntrack_put include/linux/netfilter/nf_conntrack_common.h:37 [inline]
 skb_release_head_state+0x180/0x28c net/core/skbuff.c:846
 skb_release_all net/core/skbuff.c:854 [inline]
 __kfree_skb net/core/skbuff.c:870 [inline]
 kfree_skb_reason+0x178/0x47c net/core/skbuff.c:893
 nf_hook_slow+0x188/0x1f4 net/netfilter/core.c:619
 nf_hook include/linux/netfilter.h:257 [inline]
 NF_HOOK+0x22c/0x3d4 include/linux/netfilter.h:300
 ip_local_deliver+0x11c/0x190 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:454 [inline]
 ip_rcv_finish+0x224/0x250 net/ipv4/ip_input.c:449
 NF_HOOK+0x328/0x3d4 include/linux/netfilter.h:302
 ip_rcv+0x78/0x98 net/ipv4/ip_input.c:569
 __netif_receive_skb_one_core net/core/dev.c:5528 [inline]
 __netif_receive_skb+0x18c/0x400 net/core/dev.c:5642
 process_backlog+0x410/0x784 net/core/dev.c:5970
 __napi_poll+0xb4/0x3f0 net/core/dev.c:6537
 napi_poll net/core/dev.c:6604 [inline]
 net_rx_action+0x5cc/0xd3c net/core/dev.c:6715
 __do_softirq+0x314/0xe38 kernel/softirq.c:571

The buggy address belongs to the object at ffff0000cef11400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 216 bytes inside of
 512-byte region [ffff0000cef11400, ffff0000cef11600)

The buggy address belongs to the physical page:
page:000000004c5ffd70 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10ef10
head:000000004c5ffd70 order:2 compound_mapcount:0 compound_pincount:0
flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000010200 fffffc0003512e00 dead000000000003 ffff0000c0002600
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000cef11380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff0000cef11400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff0000cef11480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff0000cef11500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff0000cef11580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/02/02 18:37 linux-6.1.y e5c3b988b827 60bf9982 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Write in nf_nat_setup_info
* Struck through repros no longer work on HEAD.