Stash

stash.asm

global ys_stash

%include "macros.asm"

ys_stash:
    pop     rbx
    cmp     r14, r15
    jne     no_allocate
    getbrk
    mov     rbp, rax
    add     rax, 0x1000
    setbrk  rax
    cmp     rax, rbp
    je      overflow
    mov     r15, rax
no_allocate:
    popb    al
    mov     [r14], al
    lea     r14, [r14+1]
    push    rbx
    ret
overflow:
    mov     rdx, err_len
    mov     rsi, err_msg
    mov     rdi, 1
    mov     rax, 1
    syscall
    mov     rdi, 3
    mov     rax, 60
    syscall

segment .data
    err_msg db 0x0a, "Error: Secondary Stack Overflowed (OOM)", 0x0a
    err_len equ $ - err_msg