panic: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/main/kernel/sys/kern/kern_synch.c", line 953
Starting stack trace...
panic(ffffffff8333e183) at panic+0x1ba sys/kern/subr_prf.c:229
__assert(ffffffff833795a7,ffffffff833d35d6,3b9,ffffffff833acb30) at __assert+0x29 sys/kern/subr_prf.c:-1
refcnt_finalize(ffff800039d5b618,ffffffff83336b14) at refcnt_finalize+0x1c8 sys/kern/kern_synch.c:954
pppx_if_destroy(0,ffff800039d5b610) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794
pppxclose(205b92,41,2000,ffff80002a910a98) at pppxclose+0xa0 sys/net/if_pppx.c:541
spec_close(ffff80003c96fb30) at spec_close+0x417 sys/kern/spec_vnops.c:-1
VOP_CLOSE(fffffd8062867a50,41,fffffd8007bfb750,ffff80002a910a98) at VOP_CLOSE+0x129 sys/kern/vfs_vops.c:156
vn_closefile(fffffd806ba4fa50,ffff80002a910a98) at vn_closefile+0x11d vn_close sys/kern/vfs_vnops.c:292 [inline]
vn_closefile(fffffd806ba4fa50,ffff80002a910a98) at vn_closefile+0x11d sys/kern/vfs_vnops.c:615
fdrop(fffffd806ba4fa50,ffff80002a910a98) at fdrop+0x121 sys/kern/kern_descrip.c:1280
closef(fffffd806ba4fa50,ffff80002a910a98) at closef+0x190 sys/kern/kern_descrip.c:1264
syscall(ffff80003c96fd80) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80003c96fd80) at syscall+0x962 sys/arch/amd64/amd64/trap.c:746
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x6496a76f4b0, count: 245
End of stack trace.