panic: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_synch.c", line 953
Starting stack trace...
panic(ffffffff833959d9) at panic+0x1d0 sys/kern/subr_prf.c:229
__assert(ffffffff833d5dca,ffffffff833e1a34,3b9,ffffffff8340b62e) at __assert+0x29 sys/kern/subr_prf.c:-1
refcnt_finalize(ffff80002a3697c8,ffffffff8338931c) at refcnt_finalize+0x1db sys/kern/kern_synch.c:954
pppx_if_destroy(ffff80002a7d1000,ffff80002a3697c0) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794
pppxclose(285b9a,41,2000,ffff800033fe7780) at pppxclose+0xa0 sys/net/if_pppx.c:541
spec_close(ffff8000357ed2d0) at spec_close+0x417 sys/kern/spec_vnops.c:-1
VOP_CLOSE(fffffd805c5f7980,41,fffffd80097fb410,ffff800033fe7780) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156
vn_closefile(fffffd806c762ac0,ffff800033fe7780) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline]
vn_closefile(fffffd806c762ac0,ffff800033fe7780) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615
fdrop(fffffd806c762ac0,ffff800033fe7780) at fdrop+0x121 sys/kern/kern_descrip.c:1280
closef(fffffd806c762ac0,ffff800033fe7780) at closef+0x192 sys/kern/kern_descrip.c:1264
syscall(ffff8000357ed530) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff8000357ed530) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:765
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x2fdd7a8a5b0, count: 245
End of stack trace.