==================================================================
BUG: KASAN: use-after-free in tcp_retransmit_timer+0x7a7/0x2ab0 net/ipv4/tcp_timer.c:535
Read of size 8 at addr ffff888028f382c0 by task kworker/u4:8/3778
CPU: 1 PID: 3778 Comm: kworker/u4:8 Not tainted 6.1.82-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Workqueue: netns cleanup_net
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
print_address_description mm/kasan/report.c:284 [inline]
print_report+0x15f/0x4f0 mm/kasan/report.c:395
kasan_report+0x136/0x160 mm/kasan/report.c:495
tcp_retransmit_timer+0x7a7/0x2ab0 net/ipv4/tcp_timer.c:535
tcp_write_timer+0x12e/0x280 net/ipv4/tcp_timer.c:665
call_timer_fn+0x1ad/0x6b0 kernel/time/timer.c:1474
expire_timers kernel/time/timer.c:1519 [inline]
__run_timers+0x67c/0x890 kernel/time/timer.c:1790
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803
__do_softirq+0x2e9/0xa4c kernel/softirq.c:571
invoke_softirq kernel/softirq.c:445 [inline]
__irq_exit_rcu+0x155/0x240 kernel/softirq.c:650
irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666
Code: 2b 00 74 08 4c 89 f7 e8 2f a5 77 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc9000451f900 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff920008a3f2c RCX: 1ffff920008a3ecc
RDX: dffffc0000000000 RSI: ffffffff8aebffc0 RDI: ffffffff8b3d2b40
RBP: ffffc9000451fa48 R08: dffffc0000000000 R09: fffffbfff2092c45
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920008a3f28
R13: dffffc0000000000 R14: ffffc9000451f960 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:319 [inline]
rcu_read_lock include/linux/rcupdate.h:760 [inline]
inet_twsk_purge+0x164/0xb60 net/ipv4/inet_timewait_sock.c:295
ops_exit_list net/core/net_namespace.c:174 [inline]
cleanup_net+0x763/0xb60 net/core/net_namespace.c:601
process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:307
Allocated by task 3563:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
__kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
slab_alloc_node mm/slub.c:3398 [inline]
slab_alloc mm/slub.c:3406 [inline]
__kmem_cache_alloc_lru mm/slub.c:3413 [inline]
kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422
kmem_cache_zalloc include/linux/slab.h:682 [inline]
net_alloc net/core/net_namespace.c:410 [inline]
copy_net_ns+0x143/0x5d0 net/core/net_namespace.c:465
create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226
ksys_unshare+0x580/0xb20 kernel/fork.c:3203
__do_sys_unshare kernel/fork.c:3274 [inline]
__se_sys_unshare kernel/fork.c:3272 [inline]
__x64_sys_unshare+0x34/0x40 kernel/fork.c:3272
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x63/0xcd
The buggy address belongs to the object at ffff888028f38000
which belongs to the cache net_namespace of size 6976
The buggy address is located 704 bytes inside of
6976-byte region [ffff888028f38000, ffff888028f39b40)
The buggy address belongs to the physical page:
page:ffffea0000a3ce00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888028f38000 pfn:0x28f38
head:ffffea0000a3ce00 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888021671741
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888140009500
raw: ffff888028f38000 0000000080040003 00000001ffffffff ffff888021671741
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3563, tgid 3563 (syz-executor.1), ts 81327436889, free_ts 81325150739
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2513
prep_new_page mm/page_alloc.c:2520 [inline]
get_page_from_freelist+0x31a1/0x3320 mm/page_alloc.c:4279
__alloc_pages+0x28d/0x770 mm/page_alloc.c:5545
alloc_slab_page+0x6a/0x150 mm/slub.c:1794
allocate_slab mm/slub.c:1939 [inline]
new_slab+0x84/0x2d0 mm/slub.c:1992
___slab_alloc+0xc20/0x1270 mm/slub.c:3180
__slab_alloc mm/slub.c:3279 [inline]
slab_alloc_node mm/slub.c:3364 [inline]
slab_alloc mm/slub.c:3406 [inline]
__kmem_cache_alloc_lru mm/slub.c:3413 [inline]
kmem_cache_alloc+0x1a5/0x2d0 mm/slub.c:3422
kmem_cache_zalloc include/linux/slab.h:682 [inline]
net_alloc net/core/net_namespace.c:410 [inline]
copy_net_ns+0x143/0x5d0 net/core/net_namespace.c:465
create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226
ksys_unshare+0x580/0xb20 kernel/fork.c:3203
__do_sys_unshare kernel/fork.c:3274 [inline]
__se_sys_unshare kernel/fork.c:3272 [inline]
__x64_sys_unshare+0x34/0x40 kernel/fork.c:3272
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x63/0xcd
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1440 [inline]
free_pcp_prepare mm/page_alloc.c:1490 [inline]
free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3358
free_unref_page+0x33/0x3e0 mm/page_alloc.c:3453
free_large_kmalloc+0xfb/0x190 mm/slab_common.c:932
skb_free_head net/core/skbuff.c:762 [inline]
skb_release_data+0x5de/0x7a0 net/core/skbuff.c:791
skb_release_all net/core/skbuff.c:856 [inline]
__kfree_skb net/core/skbuff.c:870 [inline]
consume_skb+0xa3/0x140 net/core/skbuff.c:1035
netlink_recvmsg+0x61a/0x1180 net/netlink/af_netlink.c:1952
____sys_recvmsg+0x285/0x530
___sys_recvmsg net/socket.c:2775 [inline]
__sys_recvmsg+0x2e9/0x3d0 net/socket.c:2805
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Memory state around the buggy address:
ffff888028f38180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888028f38200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888028f38280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888028f38300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888028f38380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
vkms_vblank_simulate: vblank timer overrun
----------------
Code disassembly (best guess):
0: 2b 00 sub (%rax),%eax
2: 74 08 je 0xc
4: 4c 89 f7 mov %r14,%rdi
7: e8 2f a5 77 00 call 0x77a53b
c: f6 44 24 61 02 testb $0x2,0x61(%rsp)
11: 0f 85 84 01 00 00 jne 0x19b
17: 41 f7 c7 00 02 00 00 test $0x200,%r15d
1e: 74 01 je 0x21
20: fb sti
21: 48 c7 44 24 40 0e 36 movq $0x45e0360e,0x40(%rsp)
28: e0 45
* 2a: 4b c7 44 25 00 00 00 movq $0x0,0x0(%r13,%r12,1) <-- trapping instruction
31: 00 00
33: 43 c7 44 25 09 00 00 movl $0x0,0x9(%r13,%r12,1)
3a: 00 00
3c: 43 rex.XB
3d: c7 .byte 0xc7
3e: 44 rex.R
3f: 25 .byte 0x25