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BUG: KASAN: use-after-free in memset include/linux/string.h:363 [inline]
BUG: KASAN: use-after-free in __alloc_skb+0x37b/0x5e0 net/core/skbuff.c:238
Write of size 32 at addr ffff888194ebd5c0 by task syz-executor.2/31102

CPU: 1 PID: 31102 Comm: syz-executor.2 Not tainted 5.4.0-rc7+ #0
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+0x197/0x210 lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374
 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:634
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192
 memset+0x24/0x40 mm/kasan/common.c:105
 memset include/linux/string.h:363 [inline]
 __alloc_skb+0x37b/0x5e0 net/core/skbuff.c:238
 alloc_skb include/linux/skbuff.h:1049 [inline]
 igmpv3_newpack+0x1b9/0x1110 net/ipv4/igmp.c:361
 add_grhead.isra.0+0x235/0x300 net/ipv4/igmp.c:442
 add_grec+0x842/0x1230 net/ipv4/igmp.c:575
 igmpv3_send_cr net/ipv4/igmp.c:712 [inline]
 igmp_ifc_timer_expire+0x4af/0xa00 net/ipv4/igmp.c:809
 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x6c3/0x1790 kernel/time/timer.c:1786
 __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:536 [inline]
 smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:756 [inline]
RIP: 0010:kmem_cache_free+0xab/0x320 mm/slab.c:3694
Code: e8 ea 26 00 00 84 c0 74 77 41 f7 c6 00 02 00 00 74 4f e8 58 5f ca ff 48 83 3d d0 db 44 07 00 0f 84 fa 01 00 00 4c 89 f7 57 9d <0f> 1f 44 00 00 4c 8b 6d 08 0f 1f 44 00 00 65 8b 05 20 51 53 7e 83
RSP: 0018:ffff88802b5ffb68 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000007 RBX: ffff88802a845320 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000282
RBP: ffff88802b5ffb88 R08: ffff888060660400 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88808874a380
R13: ffffffff8143f934 R14: 0000000000000282 R15: 00000000003d0f00
 delayacct_tsk_free include/linux/delayacct.h:111 [inline]
 copy_process+0x4484/0x6860 kernel/fork.c:2285
 _do_fork+0x146/0xfa0 kernel/fork.c:2366
 __do_sys_clone kernel/fork.c:2521 [inline]
 __se_sys_clone kernel/fork.c:2502 [inline]
 __x64_sys_clone+0x18d/0x250 kernel/fork.c:2502
 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45cbe9
Code: ff 48 85 f6 0f 84 d7 8c fb ff 48 83 ee 10 48 89 4e 08 48 89 3e 48 89 d7 4c 89 c2 4d 89 c8 4c 8b 54 24 08 b8 38 00 00 00 0f 05 <48> 85 c0 0f 8c ae 8c fb ff 74 01 c3 31 ed 48 f7 c7 00 00 01 00 75
RSP: 002b:0000000000a6fac8 EFLAGS: 00000202 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f7285dcb700 RCX: 000000000045cbe9
RDX: 00007f7285dcb9d0 RSI: 00007f7285dcadb0 RDI: 00000000003d0f00
RBP: 0000000000a6fce0 R08: 00007f7285dcb700 R09: 00007f7285dcb700
R10: 00007f7285dcb9d0 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000a6fb7f R14: 0000000000020000 R15: 000000000196cb70

The buggy address belongs to the page:
page:ffffea000653af40 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x6fffc0000000000()
raw: 06fffc0000000000 ffffea000653af48 ffffea000653af48 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888194ebd480: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888194ebd500: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888194ebd580: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                           ^
 ffff888194ebd600: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888194ebd680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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