panic: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_synch.c", line 995
Starting stack trace...
panic(ffffffff8347586b) at panic+0x1d0 sys/kern/subr_prf.c:229
__assert(ffffffff8341f0b2,ffffffff8342073f,3e3,ffffffff83420787) at __assert+0x29 sys/kern/subr_prf.c:-1
refcnt_finalize(ffff80003c412f30,ffffffff833676ad) at refcnt_finalize+0x1c8 sys/kern/kern_synch.c:996
pppx_if_destroy(205b9a,ffff80003c412f28) at pppx_if_destroy+0x3d sys/net/if_pppx.c:806
pppxclose(205b9a,1,2000,ffff8000ffff14a0) at pppxclose+0xa0 sys/net/if_pppx.c:553
spec_close(ffff80003c451b10) at spec_close+0x412 sys/kern/spec_vnops.c:-1
VOP_CLOSE(fffffd8070847b48,1,fffffd80097fb270,ffff8000ffff14a0) at VOP_CLOSE+0x133 sys/kern/vfs_vops.c:156
vn_closefile(fffffd806bf47e20,ffff8000ffff14a0) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline]
vn_closefile(fffffd806bf47e20,ffff8000ffff14a0) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615
fdrop(fffffd806bf47e20,ffff8000ffff14a0) at fdrop+0x126 sys/kern/kern_descrip.c:1267
closef(fffffd806bf47e20,ffff8000ffff14a0) at closef+0x192 sys/kern/kern_descrip.c:1251
syscall(ffff80003c451d70) at syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80003c451d70) at syscall+0xbc6 sys/arch/amd64/amd64/trap.c:579
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xbc45069e7c0, count: 245
End of stack trace.