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BUG: KASAN: use-after-free in tcp_probe_timer net/ipv4/tcp_timer.c:360 [inline]
BUG: KASAN: use-after-free in tcp_write_timer_handler+0x8c6/0x8d0 net/ipv4/tcp_timer.c:596
Read of size 4 at addr ffff8880979f06d0 by task syz-executor.0/9734
CPU: 1 PID: 9734 Comm: syz-executor.0 Not tainted 5.3.0-rc5+ #178
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+0x172/0x1f0 lib/dump_stack.c:113
print_address_description.cold+0xd4/0x306 mm/kasan/report.c:351
__kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482
kasan_report+0x12/0x17 mm/kasan/common.c:612
__asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131
tcp_probe_timer net/ipv4/tcp_timer.c:360 [inline]
tcp_write_timer_handler+0x8c6/0x8d0 net/ipv4/tcp_timer.c:596
tcp_write_timer+0xa8/0x1e0 net/ipv4/tcp_timer.c:612
call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1322
expire_timers kernel/time/timer.c:1366 [inline]
__run_timers kernel/time/timer.c:1685 [inline]
__run_timers kernel/time/timer.c:1653 [inline]
run_timer_softirq+0x697/0x17a0 kernel/time/timer.c:1698
__do_softirq+0x262/0x98c kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x19b/0x1e0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:537 [inline]
smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1095
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
</IRQ>
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:do_syscall_64+0x5b/0x6a0 arch/x86/entry/common.c:284
Code: ff df 48 c1 ea 03 80 3c 02 00 0f 85 99 05 00 00 48 83 3d 27 50 d2 07 00 0f 84 9f 04 00 00 e8 2c ce 71 00 fb 66 0f 1f 44 00 00 <65> 4c 8b 34 25 40 fe 01 00 48 b8 00 00 00 00 00 fc ff df 4c 89 f2
RSP: 0018:ffff88808b24ff20 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: ffff8880a4040440 RBX: 00000000000000e4 RCX: 1ffffffff134b576
RDX: 0000000000000000 RSI: ffffffff8100a304 RDI: ffffffff8100a2d6
RBP: ffff88808b24ff48 R08: ffff8880a4040440 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88808b24ff58
R13: ffffffff88d2f320 R14: 0000000000000000 R15: 0000000000000000
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c6ba
Code: 25 18 00 00 00 00 74 01 f0 48 0f b1 3d af a0 61 00 48 39 c2 75 da f3 c3 0f 1f 84 00 00 00 00 00 48 63 ff b8 e4 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 f3 c3 0f 1f 40 00 48 c7 c2 d4 ff ff ff f7
RSP: 002b:00007ffc24e0c578 EFLAGS: 00000246 ORIG_RAX: 00000000000000e4
RAX: ffffffffffffffda RBX: 000000000005a9d0 RCX: 000000000045c6ba
RDX: 0000000000000000 RSI: 00007ffc24e0c580 RDI: 0000000000000001
RBP: 00000000000006e6 R08: 0000000000000001 R09: 0000555555fea940
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000b
R13: 00007ffc24e0c5e0 R14: 000000000005a93e R15: 00007ffc24e0c5f0
Allocated by task 9741:
save_stack+0x23/0x90 mm/kasan/common.c:69
set_track mm/kasan/common.c:77 [inline]
__kasan_kmalloc mm/kasan/common.c:487 [inline]
__kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:460
kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:495
slab_post_alloc_hook mm/slab.h:520 [inline]
slab_alloc mm/slab.c:3319 [inline]
kmem_cache_alloc+0x121/0x710 mm/slab.c:3483
kmem_cache_zalloc include/linux/slab.h:738 [inline]
net_alloc net/core/net_namespace.c:410 [inline]
copy_net_ns+0xf1/0x41f net/core/net_namespace.c:462
create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:103
unshare_nsproxy_namespaces+0xc2/0x200 kernel/nsproxy.c:202
ksys_unshare+0x444/0x980 kernel/fork.c:2831
__do_sys_unshare kernel/fork.c:2899 [inline]
__se_sys_unshare kernel/fork.c:2897 [inline]
__x64_sys_unshare+0x31/0x40 kernel/fork.c:2897
do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Freed by task 9819:
save_stack+0x23/0x90 mm/kasan/common.c:69
set_track mm/kasan/common.c:77 [inline]
__kasan_slab_free+0x102/0x150 mm/kasan/common.c:449
kasan_slab_free+0xe/0x10 mm/kasan/common.c:457
__cache_free mm/slab.c:3425 [inline]
kmem_cache_free+0x86/0x320 mm/slab.c:3693
net_free net/core/net_namespace.c:438 [inline]
net_drop_ns.part.0+0x70/0x90 net/core/net_namespace.c:445
net_drop_ns net/core/net_namespace.c:444 [inline]
cleanup_net+0x774/0xa60 net/core/net_namespace.c:613
process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
worker_thread+0x98/0xe40 kernel/workqueue.c:2415
kthread+0x361/0x430 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
The buggy address belongs to the object at ffff8880979f0100
which belongs to the cache net_namespace of size 6784
The buggy address is located 1488 bytes inside of
6784-byte region [ffff8880979f0100, ffff8880979f1b80)
The buggy address belongs to the page:
page:ffffea00025e7c00 refcount:1 mapcount:0 mapping:ffff8880a9ddd000 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea000222b388 ffffea00024fde08 ffff8880a9ddd000
raw: 0000000000000000 ffff8880979f0100 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8880979f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880979f0600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880979f0680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880979f0700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880979f0780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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