syzbot

panic: ASan: Invalid access, 8-byte write at 0xfffffe0007836ff8, MallocRedZone(fb)
cpuid = 0
time = 1
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0xc7/frame 0xffffffff84f46530
kdb_backtrace() at kdb_backtrace+0xd3/frame 0xffffffff84f46690
vpanic() at vpanic+0x2c5/frame 0xffffffff84f46770
panic() at panic+0xb5/frame 0xffffffff84f46830
kasan_atomic_testandset_long() at kasan_atomic_testandset_long+0x384/frame 0xffffffff84f468f0
item_ctor() at item_ctor+0x4da/frame 0xffffffff84f46950
malloc() at malloc+0x1b5/frame 0xffffffff84f46a30
init_dynamic_kenv_from() at init_dynamic_kenv_from+0x296/frame 0xffffffff84f46ab0
init_dynamic_kenv() at init_dynamic_kenv+0x144/frame 0xffffffff84f46b70
mi_startup() at mi_startup+0x457/frame 0xffffffff84f46cb0
btext() at btext+0x22
KDB: enter: panic
[ thread pid 0 tid 0 ]
Stopped at      kdb_enter+0x6b: movq    $0,0x28f874a(%rip)
db>