kernel panic at /syzkaller/managers/main/kernel/kern/include/kref.h:68, from core 3: assertion failed: kref_refcnt(kref) > 0
Stack Backtrace on Core 3:
#01 [<0xffffffffc200a33c>] in backtrace at src/kdebug.c:229
#02 [<0xffffffffc2009acd>] in _panic at src/init.c:267
#03 [<0xffffffffc20312bb>] in kref_put at include/kref.h:68
#04 [<0xffffffffc2031978>] in cclose at src/ns/chan.c:334
#05 [<0xffffffffc2033379>] in walk_symlink at src/ns/chan.c:1703
#06 [<0xffffffffc2033364>] in walk_symlink at src/ns/chan.c:1701
#07 [<0xffffffffc2033364>] in walk_symlink at src/ns/chan.c:1701
#08 [<0xffffffffc2033364>] in walk_symlink at src/ns/chan.c:1701
#09 [<0xffffffffc2033364>] in walk_symlink at src/ns/chan.c:1701
#10 [<0xffffffffc2033364>] in walk_symlink at src/ns/chan.c:1701
#11 [<0xffffffffc2033364>] in walk_symlink at src/ns/chan.c:1701
#12 [<0xffffffffc2032e82>] in walk at src/ns/chan.c:872
#13 [<0xffffffffc2033559>] in __namec_from at src/ns/chan.c:1139
#14 [<0xffffffffc203413f>] in namec at src/ns/chan.c:1517
#15 [<0xffffffffc203da3d>] in sysunmount at src/ns/sysfile.c:561
#16 [<0xffffffffc20565ad>] in sys_nunmount at src/syscall.c:2226
#17 [<0xffffffffc2059f09>] in syscall at src/syscall.c:2465
#18 [<0xffffffffc205a0d4>] in run_local_syscall at src/syscall.c:2500
#19 [<0xffffffffc205a609>] in prep_syscalls at src/syscall.c:2520
#20 [<0xffffffffc20abc0a>] in sysenter_callwrapper at arch/x86/trap.c:854