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BUG: KASAN: use-after-free in inet_frag_destroy_rcu+0xd9/0xe0 net/ipv4/inet_fragment.c:201
Read of size 8 at addr ffff88808d8d52d8 by task syz-executor.4/8629
CPU: 0 PID: 8629 Comm: syz-executor.4 Not tainted 5.2.0-rc1+ #3
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+0x7c/0x20d mm/kasan/report.c:188
__kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
kasan_report+0x12/0x20 mm/kasan/common.c:614
__asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132
inet_frag_destroy_rcu+0xd9/0xe0 net/ipv4/inet_fragment.c:201
__rcu_reclaim kernel/rcu/rcu.h:222 [inline]
rcu_do_batch kernel/rcu/tree.c:2092 [inline]
invoke_rcu_callbacks kernel/rcu/tree.c:2310 [inline]
rcu_core+0xba5/0x1500 kernel/rcu/tree.c:2291
__do_softirq+0x25c/0x94c kernel/softirq.c:293
invoke_softirq kernel/softirq.c:374 [inline]
irq_exit+0x180/0x1d0 kernel/softirq.c:414
exiting_irq arch/x86/include/asm/apic.h:536 [inline]
smp_apic_timer_interrupt+0x13b/0x550 arch/x86/kernel/apic/apic.c:1068
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:806
</IRQ>
RIP: 0010:do_syscall_64+0xed/0x680 arch/x86/entry/common.c:301
Code: 48 81 fb 24 02 00 00 48 19 f6 48 b8 00 00 00 00 00 fc ff df 48 21 f3 48 8d 3c dd c0 47 60 87 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 4e 05 00 00 4c 89 e7 ff 14 dd c0 47 60 87 49 8d 7c 24 50 48
RSP: 0018:ffff8880908d7f20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: 000000000000003d RCX: ffffffff8100a055
RDX: 1ffffffff0ec0935 RSI: ffffffffffffffff RDI: ffffffff876049a8
RBP: ffff8880908d7f48 R08: ffff8880908ca280 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880908d7f58
R13: ffffffff88b27080 R14: 0000000000000000 R15: 0000000000000000
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x41320a
Code: 0f 83 6a 18 00 00 c3 66 0f 1f 84 00 00 00 00 00 8b 05 8e 30 66 00 85 c0 75 36 45 31 d2 48 63 d2 48 63 ff b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 d4 ff ff ff f7
RSP: 002b:00007ffe0134df78 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: ffffffffffffffda RBX: 0000000000037631 RCX: 000000000041320a
RDX: 0000000040000001 RSI: 00007ffe0134dfb0 RDI: ffffffffffffffff
RBP: 0000000000000146 R08: 0000000000000001 R09: 000055555639e940
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000b
R13: 00007ffe0134dfb0 R14: 0000000000037304 R15: 00007ffe0134dfc0
Allocated by task 8626:
save_stack+0x23/0x90 mm/kasan/common.c:71
set_track mm/kasan/common.c:79 [inline]
__kasan_kmalloc mm/kasan/common.c:489 [inline]
__kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462
kasan_kmalloc+0x9/0x10 mm/kasan/common.c:503
kmem_cache_alloc_trace+0x151/0x750 mm/slab.c:3555
kmalloc include/linux/slab.h:547 [inline]
kzalloc include/linux/slab.h:742 [inline]
fqdir_init include/net/inet_frag.h:115 [inline]
ipv6_frags_init_net+0x48/0x460 net/ipv6/reassembly.c:513
ops_init+0xb3/0x410 net/core/net_namespace.c:130
setup_net+0x2d3/0x740 net/core/net_namespace.c:316
copy_net_ns+0x1df/0x340 net/core/net_namespace.c:439
create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:107
unshare_nsproxy_namespaces+0xc2/0x200 kernel/nsproxy.c:206
ksys_unshare+0x440/0x980 kernel/fork.c:2692
__do_sys_unshare kernel/fork.c:2760 [inline]
__se_sys_unshare kernel/fork.c:2758 [inline]
__x64_sys_unshare+0x31/0x40 kernel/fork.c:2758
do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Freed by task 11522:
save_stack+0x23/0x90 mm/kasan/common.c:71
set_track mm/kasan/common.c:79 [inline]
__kasan_slab_free+0x102/0x150 mm/kasan/common.c:451
kasan_slab_free+0xe/0x10 mm/kasan/common.c:459
__cache_free mm/slab.c:3432 [inline]
kfree+0xcf/0x220 mm/slab.c:3755
fqdir_rwork_fn+0x33/0x40 net/ipv4/inet_fragment.c:154
process_one_work+0x989/0x1790 kernel/workqueue.c:2269
worker_thread+0x98/0xe40 kernel/workqueue.c:2415
kthread+0x354/0x420 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
The buggy address belongs to the object at ffff88808d8d52c0
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 24 bytes inside of
512-byte region [ffff88808d8d52c0, ffff88808d8d54c0)
The buggy address belongs to the page:
page:ffffea0002363540 refcount:1 mapcount:0 mapping:ffff8880aa400940 index:0x0
flags: 0x1fffc0000000200(slab)
raw: 01fffc0000000200 ffffea00023e7e88 ffffea0002a453c8 ffff8880aa400940
raw: 0000000000000000 ffff88808d8d5040 0000000100000006 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88808d8d5180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88808d8d5200: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff88808d8d5280: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
^
ffff88808d8d5300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88808d8d5380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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