[v6.1] KASAN: use-after-free Write in br_multicast_set_port_router
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syzbot
Jan 27, 2026, 10:20:29 AM (yesterday) Jan 27
to syzkaller...@googlegroups.com
Hello,
syzbot found the following issue on:
HEAD commit: cd9b81672742 Linux 6.1.161
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13a8e5ac580000
kernel config: https://syzkaller.appspot.com/x/.config?x=b1adc0bfde2d8a4a
dashboard link: https://syzkaller.appspot.com/bug?extid=b7ac43ba37694014118e
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
userspace arch: arm64
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d21df4411014/disk-cd9b8167.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/246aed0358fb/vmlinux-cd9b8167.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a6f546504ec2/Image-cd9b8167.gz.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b7ac43...@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:884 [inline]
BUG: KASAN: use-after-free in hlist_del_init_rcu include/linux/rculist.h:184 [inline]
BUG: KASAN: use-after-free in br_multicast_rport_del net/bridge/br_multicast.c:1476 [inline]
BUG: KASAN: use-after-free in br_ip4_multicast_rport_del net/bridge/br_multicast.c:1482 [inline]
BUG: KASAN: use-after-free in br_multicast_set_port_router+0x278/0x9e0 net/bridge/br_multicast.c:4380
Write of size 8 at addr ffff0000f599ba68 by task syz.0.1134/8238
CPU: 1 PID: 8238 Comm: syz.0.1134 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
Call trace:
dump_backtrace+0x1c0/0x1ec arch/arm64/kernel/stacktrace.c:158
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
__dump_stack+0x30/0x40 lib/dump_stack.c:88
dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106
print_address_description+0x88/0x218 mm/kasan/report.c:316
print_report+0x50/0x68 mm/kasan/report.c:420
kasan_report+0xa8/0xfc mm/kasan/report.c:524
__asan_report_store8_noabort+0x2c/0x38 mm/kasan/report_generic.c:356
__hlist_del include/linux/list.h:884 [inline]
hlist_del_init_rcu include/linux/rculist.h:184 [inline]
br_multicast_rport_del net/bridge/br_multicast.c:1476 [inline]
br_ip4_multicast_rport_del net/bridge/br_multicast.c:1482 [inline]
br_multicast_set_port_router+0x278/0x9e0 net/bridge/br_multicast.c:4380
br_setport+0xa20/0xf54 net/bridge/br_netlink.c:986
br_port_slave_changelink+0x138/0x160 net/bridge/br_netlink.c:1159
__rtnl_newlink net/core/rtnetlink.c:3601 [inline]
rtnl_newlink+0x10b8/0x1a50 net/core/rtnetlink.c:3655
rtnetlink_rcv_msg+0x698/0xcdc net/core/rtnetlink.c:6150
netlink_rcv_skb+0x218/0x3e8 net/netlink/af_netlink.c:2511
rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6168
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x60c/0x814 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x6f4/0x9c0 net/netlink/af_netlink.c:1872
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x5c8/0x938 net/socket.c:2518
___sys_sendmsg net/socket.c:2572 [inline]
__sys_sendmsg+0x288/0x374 net/socket.c:2601
__do_sys_sendmsg net/socket.c:2610 [inline]
__se_sys_sendmsg net/socket.c:2608 [inline]
__arm64_sys_sendmsg+0x80/0x94 net/socket.c:2608
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 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 8209:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505
____kasan_kmalloc mm/kasan/common.c:375 [inline]
__kasan_kmalloc+0xa0/0xb8 mm/kasan/common.c:384
kasan_kmalloc include/linux/kasan.h:211 [inline]
__do_kmalloc_node mm/slab_common.c:936 [inline]
__kmalloc_node_track_caller+0xe0/0x16c mm/slab_common.c:956
kmalloc_reserve net/core/skbuff.c:446 [inline]
__alloc_skb+0x264/0x714 net/core/skbuff.c:515
alloc_skb_fclone include/linux/skbuff.h:1321 [inline]
tipc_buf_acquire net/tipc/msg.c:72 [inline]
tipc_msg_build+0xc0/0xb9c net/tipc/msg.c:390
tipc_send_group_bcast+0x814/0xacc net/tipc/socket.c:1128
__tipc_sendmsg+0x2ac/0x28b8 net/tipc/socket.c:1436
tipc_sendmsg+0x60/0x1bc net/tipc/socket.c:1403
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x5c8/0x938 net/socket.c:2518
___sys_sendmsg net/socket.c:2572 [inline]
__sys_sendmmsg+0x344/0x834 net/socket.c:2658
__do_sys_sendmmsg net/socket.c:2687 [inline]
__se_sys_sendmmsg net/socket.c:2684 [inline]
__arm64_sys_sendmmsg+0xa0/0xbc net/socket.c:2684
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 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
Freed by task 8209:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516
____kasan_slab_free+0x148/0x1b0 mm/kasan/common.c:237
__kasan_slab_free+0x18/0x28 mm/kasan/common.c:245
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1729 [inline]
slab_free_freelist_hook+0x16c/0x1e8 mm/slub.c:1755
slab_free mm/slub.c:3687 [inline]
__kmem_cache_free+0xbc/0x218 mm/slub.c:3700
kfree+0xd0/0x1a8 mm/slab_common.c:988
skb_free_head net/core/skbuff.c:762 [inline]
skb_release_data+0x434/0x63c net/core/skbuff.c:791
skb_release_all net/core/skbuff.c:856 [inline]
__kfree_skb net/core/skbuff.c:870 [inline]
kfree_skb_reason+0x198/0x418 net/core/skbuff.c:893
kfree_skb include/linux/skbuff.h:1220 [inline]
__skb_queue_purge include/linux/skbuff.h:3183 [inline]
tipc_mcast_xmit+0xe84/0x1324 net/tipc/bcast.c:428
tipc_send_group_bcast+0x840/0xacc net/tipc/socket.c:1133
__tipc_sendmsg+0x2ac/0x28b8 net/tipc/socket.c:1436
tipc_sendmsg+0x60/0x1bc net/tipc/socket.c:1403
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x5c8/0x938 net/socket.c:2518
___sys_sendmsg net/socket.c:2572 [inline]
__sys_sendmmsg+0x344/0x834 net/socket.c:2658
__do_sys_sendmmsg net/socket.c:2687 [inline]
__se_sys_sendmmsg net/socket.c:2684 [inline]
__arm64_sys_sendmmsg+0xa0/0xbc net/socket.c:2684
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 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
Last potentially related work creation:
kasan_save_stack+0x40/0x70 mm/kasan/common.c:46
__kasan_record_aux_stack+0xc0/0xdc mm/kasan/generic.c:486
kasan_record_aux_stack_noalloc+0x14/0x20 mm/kasan/generic.c:496
call_rcu+0x100/0x94c kernel/rcu/tree.c:2849
del_nbp+0x814/0x904 net/bridge/br_if.c:376
br_del_if+0x154/0x320 net/bridge/br_if.c:740
br_del_slave+0x28/0x38 net/bridge/br_device.c:395
do_set_master net/core/rtnetlink.c:2616 [inline]
do_setlink+0xc28/0x3434 net/core/rtnetlink.c:2840
__rtnl_newlink net/core/rtnetlink.c:3608 [inline]
rtnl_newlink+0x13cc/0x1a50 net/core/rtnetlink.c:3655
rtnetlink_rcv_msg+0x698/0xcdc net/core/rtnetlink.c:6150
netlink_rcv_skb+0x218/0x3e8 net/netlink/af_netlink.c:2511
rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6168
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x60c/0x814 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x6f4/0x9c0 net/netlink/af_netlink.c:1872
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x5c8/0x938 net/socket.c:2518
___sys_sendmsg net/socket.c:2572 [inline]
__sys_sendmsg+0x288/0x374 net/socket.c:2601
__do_sys_sendmsg net/socket.c:2610 [inline]
__se_sys_sendmsg net/socket.c:2608 [inline]
__arm64_sys_sendmsg+0x80/0x94 net/socket.c:2608
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 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
Second to last potentially related work creation:
kasan_save_stack+0x40/0x70 mm/kasan/common.c:46
__kasan_record_aux_stack+0xc0/0xdc mm/kasan/generic.c:486
kasan_record_aux_stack_noalloc+0x14/0x20 mm/kasan/generic.c:496
kvfree_call_rcu+0xb4/0x6e8 kernel/rcu/tree.c:3405
neigh_destroy+0x458/0x650 net/core/neighbour.c:923
neigh_release include/net/neighbour.h:448 [inline]
neigh_cleanup_and_release+0x154/0x3b4 net/core/neighbour.c:104
neigh_del net/core/neighbour.c:226 [inline]
neigh_remove_one+0x318/0x420 net/core/neighbour.c:247
neigh_forced_gc net/core/neighbour.c:280 [inline]
neigh_alloc net/core/neighbour.c:486 [inline]
___neigh_create+0x450/0x2400 net/core/neighbour.c:649
__neigh_create+0x44/0x58 net/core/neighbour.c:738
ip6_finish_output2+0x1678/0x1840 net/ipv6/ip6_output.c:129
__ip6_finish_output net/ipv6/ip6_output.c:205 [inline]
ip6_finish_output+0x594/0x92c net/ipv6/ip6_output.c:216
NF_HOOK_COND include/linux/netfilter.h:291 [inline]
ip6_output+0x274/0x500 net/ipv6/ip6_output.c:237
dst_output include/net/dst.h:453 [inline]
NF_HOOK include/linux/netfilter.h:302 [inline]
ndisc_send_skb+0xc30/0x164c net/ipv6/ndisc.c:513
ndisc_send_ns net/ipv6/ndisc.c:671 [inline]
ndisc_solicit+0x29c/0x52c net/ipv6/ndisc.c:763
neigh_probe+0xc4/0x124 net/core/neighbour.c:1080
__neigh_event_send+0xd00/0x1490 net/core/neighbour.c:1247
neigh_event_send_probe include/net/neighbour.h:469 [inline]
neigh_event_send include/net/neighbour.h:475 [inline]
neigh_resolve_output+0x180/0x650 net/core/neighbour.c:1552
neigh_output include/net/neighbour.h:545 [inline]
ip6_finish_output2+0xd5c/0x1840 net/ipv6/ip6_output.c:138
__ip6_finish_output net/ipv6/ip6_output.c:205 [inline]
ip6_finish_output+0x594/0x92c net/ipv6/ip6_output.c:216
NF_HOOK_COND include/linux/netfilter.h:291 [inline]
ip6_output+0x274/0x500 net/ipv6/ip6_output.c:237
dst_output include/net/dst.h:453 [inline]
NF_HOOK include/linux/netfilter.h:302 [inline]
ip6_xmit+0x1164/0x1a24 net/ipv6/ip6_output.c:357
tcp_v6_send_synack+0x624/0xb54 net/ipv6/tcp_ipv6.c:567
tcp_conn_request+0x18b8/0x25d4 net/ipv4/tcp_input.c:7147
tcp_v6_conn_request+0x264/0x37c net/ipv6/tcp_ipv6.c:1177
tcp_rcv_state_process+0x121c/0x3854 net/ipv4/tcp_input.c:6583
tcp_v6_do_rcv+0x868/0x1128 net/ipv6/tcp_ipv6.c:1510
tcp_v6_rcv+0x19cc/0x2000 net/ipv6/tcp_ipv6.c:1739
ip6_protocol_deliver_rcu+0x928/0x11cc net/ipv6/ip6_input.c:438
ip6_input_finish+0x164/0x294 net/ipv6/ip6_input.c:483
NF_HOOK+0x2dc/0x36c include/linux/netfilter.h:302
ip6_input+0x90/0xa8 net/ipv6/ip6_input.c:492
dst_input include/net/dst.h:463 [inline]
ip6_rcv_finish+0x1f4/0x220 net/ipv6/ip6_input.c:79
NF_HOOK+0x2dc/0x36c include/linux/netfilter.h:302
ipv6_rcv+0x9c/0xbc net/ipv6/ip6_input.c:310
__netif_receive_skb_one_core net/core/dev.c:5581 [inline]
__netif_receive_skb+0xcc/0x2a8 net/core/dev.c:5695
netif_receive_skb_internal net/core/dev.c:5781 [inline]
netif_receive_skb+0x1e8/0x924 net/core/dev.c:5840
tun_rx_batched+0x48c/0x5dc drivers/net/tun.c:-1
tun_get_user+0x1fe8/0x3298 drivers/net/tun.c:1998
tun_chr_write_iter+0xfc/0x200 drivers/net/tun.c:2044
call_write_iter include/linux/fs.h:2265 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x3ec/0x7f0 fs/read_write.c:584
ksys_write+0x12c/0x224 fs/read_write.c:637
__do_sys_write fs/read_write.c:649 [inline]
__se_sys_write fs/read_write.c:646 [inline]
__arm64_sys_write+0x7c/0x90 fs/read_write.c:646
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 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
The buggy address belongs to the object at ffff0000f599b800
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 616 bytes inside of
1024-byte region [ffff0000f599b800, ffff0000f599bc00)
The buggy address belongs to the physical page:
page:00000000535a3200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x135998
head:00000000535a3200 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000010200 fffffc0003309c00 dead000000000002 ffff0000c0002780
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff0000f599b900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff0000f599b980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff0000f599ba00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff0000f599ba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff0000f599bb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
syzbot found the following issue on:
HEAD commit: cd9b81672742 Linux 6.1.161
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13a8e5ac580000
kernel config: https://syzkaller.appspot.com/x/.config?x=b1adc0bfde2d8a4a
dashboard link: https://syzkaller.appspot.com/bug?extid=b7ac43ba37694014118e
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
userspace arch: arm64
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d21df4411014/disk-cd9b8167.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/246aed0358fb/vmlinux-cd9b8167.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a6f546504ec2/Image-cd9b8167.gz.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b7ac43...@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:884 [inline]
BUG: KASAN: use-after-free in hlist_del_init_rcu include/linux/rculist.h:184 [inline]
BUG: KASAN: use-after-free in br_multicast_rport_del net/bridge/br_multicast.c:1476 [inline]
BUG: KASAN: use-after-free in br_ip4_multicast_rport_del net/bridge/br_multicast.c:1482 [inline]
BUG: KASAN: use-after-free in br_multicast_set_port_router+0x278/0x9e0 net/bridge/br_multicast.c:4380
Write of size 8 at addr ffff0000f599ba68 by task syz.0.1134/8238
CPU: 1 PID: 8238 Comm: syz.0.1134 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
Call trace:
dump_backtrace+0x1c0/0x1ec arch/arm64/kernel/stacktrace.c:158
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
__dump_stack+0x30/0x40 lib/dump_stack.c:88
dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106
print_address_description+0x88/0x218 mm/kasan/report.c:316
print_report+0x50/0x68 mm/kasan/report.c:420
kasan_report+0xa8/0xfc mm/kasan/report.c:524
__asan_report_store8_noabort+0x2c/0x38 mm/kasan/report_generic.c:356
__hlist_del include/linux/list.h:884 [inline]
hlist_del_init_rcu include/linux/rculist.h:184 [inline]
br_multicast_rport_del net/bridge/br_multicast.c:1476 [inline]
br_ip4_multicast_rport_del net/bridge/br_multicast.c:1482 [inline]
br_multicast_set_port_router+0x278/0x9e0 net/bridge/br_multicast.c:4380
br_setport+0xa20/0xf54 net/bridge/br_netlink.c:986
br_port_slave_changelink+0x138/0x160 net/bridge/br_netlink.c:1159
__rtnl_newlink net/core/rtnetlink.c:3601 [inline]
rtnl_newlink+0x10b8/0x1a50 net/core/rtnetlink.c:3655
rtnetlink_rcv_msg+0x698/0xcdc net/core/rtnetlink.c:6150
netlink_rcv_skb+0x218/0x3e8 net/netlink/af_netlink.c:2511
rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6168
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x60c/0x814 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x6f4/0x9c0 net/netlink/af_netlink.c:1872
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x5c8/0x938 net/socket.c:2518
___sys_sendmsg net/socket.c:2572 [inline]
__sys_sendmsg+0x288/0x374 net/socket.c:2601
__do_sys_sendmsg net/socket.c:2610 [inline]
__se_sys_sendmsg net/socket.c:2608 [inline]
__arm64_sys_sendmsg+0x80/0x94 net/socket.c:2608
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 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 8209:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505
____kasan_kmalloc mm/kasan/common.c:375 [inline]
__kasan_kmalloc+0xa0/0xb8 mm/kasan/common.c:384
kasan_kmalloc include/linux/kasan.h:211 [inline]
__do_kmalloc_node mm/slab_common.c:936 [inline]
__kmalloc_node_track_caller+0xe0/0x16c mm/slab_common.c:956
kmalloc_reserve net/core/skbuff.c:446 [inline]
__alloc_skb+0x264/0x714 net/core/skbuff.c:515
alloc_skb_fclone include/linux/skbuff.h:1321 [inline]
tipc_buf_acquire net/tipc/msg.c:72 [inline]
tipc_msg_build+0xc0/0xb9c net/tipc/msg.c:390
tipc_send_group_bcast+0x814/0xacc net/tipc/socket.c:1128
__tipc_sendmsg+0x2ac/0x28b8 net/tipc/socket.c:1436
tipc_sendmsg+0x60/0x1bc net/tipc/socket.c:1403
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x5c8/0x938 net/socket.c:2518
___sys_sendmsg net/socket.c:2572 [inline]
__sys_sendmmsg+0x344/0x834 net/socket.c:2658
__do_sys_sendmmsg net/socket.c:2687 [inline]
__se_sys_sendmmsg net/socket.c:2684 [inline]
__arm64_sys_sendmmsg+0xa0/0xbc net/socket.c:2684
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 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
Freed by task 8209:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516
____kasan_slab_free+0x148/0x1b0 mm/kasan/common.c:237
__kasan_slab_free+0x18/0x28 mm/kasan/common.c:245
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1729 [inline]
slab_free_freelist_hook+0x16c/0x1e8 mm/slub.c:1755
slab_free mm/slub.c:3687 [inline]
__kmem_cache_free+0xbc/0x218 mm/slub.c:3700
kfree+0xd0/0x1a8 mm/slab_common.c:988
skb_free_head net/core/skbuff.c:762 [inline]
skb_release_data+0x434/0x63c net/core/skbuff.c:791
skb_release_all net/core/skbuff.c:856 [inline]
__kfree_skb net/core/skbuff.c:870 [inline]
kfree_skb_reason+0x198/0x418 net/core/skbuff.c:893
kfree_skb include/linux/skbuff.h:1220 [inline]
__skb_queue_purge include/linux/skbuff.h:3183 [inline]
tipc_mcast_xmit+0xe84/0x1324 net/tipc/bcast.c:428
tipc_send_group_bcast+0x840/0xacc net/tipc/socket.c:1133
__tipc_sendmsg+0x2ac/0x28b8 net/tipc/socket.c:1436
tipc_sendmsg+0x60/0x1bc net/tipc/socket.c:1403
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x5c8/0x938 net/socket.c:2518
___sys_sendmsg net/socket.c:2572 [inline]
__sys_sendmmsg+0x344/0x834 net/socket.c:2658
__do_sys_sendmmsg net/socket.c:2687 [inline]
__se_sys_sendmmsg net/socket.c:2684 [inline]
__arm64_sys_sendmmsg+0xa0/0xbc net/socket.c:2684
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 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
Last potentially related work creation:
kasan_save_stack+0x40/0x70 mm/kasan/common.c:46
__kasan_record_aux_stack+0xc0/0xdc mm/kasan/generic.c:486
kasan_record_aux_stack_noalloc+0x14/0x20 mm/kasan/generic.c:496
call_rcu+0x100/0x94c kernel/rcu/tree.c:2849
del_nbp+0x814/0x904 net/bridge/br_if.c:376
br_del_if+0x154/0x320 net/bridge/br_if.c:740
br_del_slave+0x28/0x38 net/bridge/br_device.c:395
do_set_master net/core/rtnetlink.c:2616 [inline]
do_setlink+0xc28/0x3434 net/core/rtnetlink.c:2840
__rtnl_newlink net/core/rtnetlink.c:3608 [inline]
rtnl_newlink+0x13cc/0x1a50 net/core/rtnetlink.c:3655
rtnetlink_rcv_msg+0x698/0xcdc net/core/rtnetlink.c:6150
netlink_rcv_skb+0x218/0x3e8 net/netlink/af_netlink.c:2511
rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6168
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x60c/0x814 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x6f4/0x9c0 net/netlink/af_netlink.c:1872
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x5c8/0x938 net/socket.c:2518
___sys_sendmsg net/socket.c:2572 [inline]
__sys_sendmsg+0x288/0x374 net/socket.c:2601
__do_sys_sendmsg net/socket.c:2610 [inline]
__se_sys_sendmsg net/socket.c:2608 [inline]
__arm64_sys_sendmsg+0x80/0x94 net/socket.c:2608
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 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
Second to last potentially related work creation:
kasan_save_stack+0x40/0x70 mm/kasan/common.c:46
__kasan_record_aux_stack+0xc0/0xdc mm/kasan/generic.c:486
kasan_record_aux_stack_noalloc+0x14/0x20 mm/kasan/generic.c:496
kvfree_call_rcu+0xb4/0x6e8 kernel/rcu/tree.c:3405
neigh_destroy+0x458/0x650 net/core/neighbour.c:923
neigh_release include/net/neighbour.h:448 [inline]
neigh_cleanup_and_release+0x154/0x3b4 net/core/neighbour.c:104
neigh_del net/core/neighbour.c:226 [inline]
neigh_remove_one+0x318/0x420 net/core/neighbour.c:247
neigh_forced_gc net/core/neighbour.c:280 [inline]
neigh_alloc net/core/neighbour.c:486 [inline]
___neigh_create+0x450/0x2400 net/core/neighbour.c:649
__neigh_create+0x44/0x58 net/core/neighbour.c:738
ip6_finish_output2+0x1678/0x1840 net/ipv6/ip6_output.c:129
__ip6_finish_output net/ipv6/ip6_output.c:205 [inline]
ip6_finish_output+0x594/0x92c net/ipv6/ip6_output.c:216
NF_HOOK_COND include/linux/netfilter.h:291 [inline]
ip6_output+0x274/0x500 net/ipv6/ip6_output.c:237
dst_output include/net/dst.h:453 [inline]
NF_HOOK include/linux/netfilter.h:302 [inline]
ndisc_send_skb+0xc30/0x164c net/ipv6/ndisc.c:513
ndisc_send_ns net/ipv6/ndisc.c:671 [inline]
ndisc_solicit+0x29c/0x52c net/ipv6/ndisc.c:763
neigh_probe+0xc4/0x124 net/core/neighbour.c:1080
__neigh_event_send+0xd00/0x1490 net/core/neighbour.c:1247
neigh_event_send_probe include/net/neighbour.h:469 [inline]
neigh_event_send include/net/neighbour.h:475 [inline]
neigh_resolve_output+0x180/0x650 net/core/neighbour.c:1552
neigh_output include/net/neighbour.h:545 [inline]
ip6_finish_output2+0xd5c/0x1840 net/ipv6/ip6_output.c:138
__ip6_finish_output net/ipv6/ip6_output.c:205 [inline]
ip6_finish_output+0x594/0x92c net/ipv6/ip6_output.c:216
NF_HOOK_COND include/linux/netfilter.h:291 [inline]
ip6_output+0x274/0x500 net/ipv6/ip6_output.c:237
dst_output include/net/dst.h:453 [inline]
NF_HOOK include/linux/netfilter.h:302 [inline]
ip6_xmit+0x1164/0x1a24 net/ipv6/ip6_output.c:357
tcp_v6_send_synack+0x624/0xb54 net/ipv6/tcp_ipv6.c:567
tcp_conn_request+0x18b8/0x25d4 net/ipv4/tcp_input.c:7147
tcp_v6_conn_request+0x264/0x37c net/ipv6/tcp_ipv6.c:1177
tcp_rcv_state_process+0x121c/0x3854 net/ipv4/tcp_input.c:6583
tcp_v6_do_rcv+0x868/0x1128 net/ipv6/tcp_ipv6.c:1510
tcp_v6_rcv+0x19cc/0x2000 net/ipv6/tcp_ipv6.c:1739
ip6_protocol_deliver_rcu+0x928/0x11cc net/ipv6/ip6_input.c:438
ip6_input_finish+0x164/0x294 net/ipv6/ip6_input.c:483
NF_HOOK+0x2dc/0x36c include/linux/netfilter.h:302
ip6_input+0x90/0xa8 net/ipv6/ip6_input.c:492
dst_input include/net/dst.h:463 [inline]
ip6_rcv_finish+0x1f4/0x220 net/ipv6/ip6_input.c:79
NF_HOOK+0x2dc/0x36c include/linux/netfilter.h:302
ipv6_rcv+0x9c/0xbc net/ipv6/ip6_input.c:310
__netif_receive_skb_one_core net/core/dev.c:5581 [inline]
__netif_receive_skb+0xcc/0x2a8 net/core/dev.c:5695
netif_receive_skb_internal net/core/dev.c:5781 [inline]
netif_receive_skb+0x1e8/0x924 net/core/dev.c:5840
tun_rx_batched+0x48c/0x5dc drivers/net/tun.c:-1
tun_get_user+0x1fe8/0x3298 drivers/net/tun.c:1998
tun_chr_write_iter+0xfc/0x200 drivers/net/tun.c:2044
call_write_iter include/linux/fs.h:2265 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x3ec/0x7f0 fs/read_write.c:584
ksys_write+0x12c/0x224 fs/read_write.c:637
__do_sys_write fs/read_write.c:649 [inline]
__se_sys_write fs/read_write.c:646 [inline]
__arm64_sys_write+0x7c/0x90 fs/read_write.c:646
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 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
The buggy address belongs to the object at ffff0000f599b800
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 616 bytes inside of
1024-byte region [ffff0000f599b800, ffff0000f599bc00)
The buggy address belongs to the physical page:
page:00000000535a3200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x135998
head:00000000535a3200 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000010200 fffffc0003309c00 dead000000000002 ffff0000c0002780
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff0000f599b900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff0000f599b980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff0000f599ba00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff0000f599ba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff0000f599bb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
---
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