Uninitialized segs[1]/segs[0] dereference when fewer than 2 PT_LOAD segments

Summary

link_elf_load_file (link_elf.c:399 segs[2] uninit stack; :531 checks phdyn!=NULL but NOT nsegs==2; :541-542 unconditionally derefs segs[0]->p_vaddr and segs[1]->p_vaddr+segs[1]->p_memsz). Crafted ELF with PT_DYNAMIC but 0/1 PT_LOAD -> wild deref of uninitialized stack pointer -> panic. Root-only defense-in-depth.