int
exec_setup_stack(struct lwp *l, struct exec_package *epp)
{
u_long max_stack_size;
u_long access_linear_min, access_size;
u_long noaccess_linear_min, noaccess_size;
#ifndef USRSTACK32
#define USRSTACK32 (0x00000000ffffffffL&~PGOFSET)
#endif
if (epp->ep_flags & EXEC_32) {
epp->ep_minsaddr = USRSTACK32;
max_stack_size = MAXSSIZ;
} else {
epp->ep_minsaddr = USRSTACK;
max_stack_size = MAXSSIZ;
}
epp->ep_ssize = l->l_proc->p_rlimit[RLIMIT_STACK].rlim_cur;
#ifdef PAX_ASLR
pax_aslr_stack(l, epp, &max_stack_size);
#endif /* PAX_ASLR */
l->l_proc->p_stackbase = epp->ep_minsaddr;
epp->ep_maxsaddr = (u_long)STACK_GROW(epp->ep_minsaddr,
max_stack_size);
/*
* set up commands for stack. note that this takes *two*, one to
* map the part of the stack which we can access, and one to map
* the part which we can't.
*
* arguably, it could be made into one, but that would require the
* addition of another mapping proc, which is unnecessary
*/
access_size = epp->ep_ssize;
access_linear_min = (u_long)STACK_ALLOC(epp->ep_minsaddr, access_size);
noaccess_size = max_stack_size - access_size;
noaccess_linear_min = (u_long)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr,
access_size), noaccess_size);
if (noaccess_size > 0 && noaccess_size <= MAXSSIZ) {
NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, noaccess_size,
noaccess_linear_min, NULL, 0, VM_PROT_NONE, VMCMD_STACK);
}
KASSERT(access_size > 0 && access_size <= MAXSSIZ);
NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, access_size,
access_linear_min, NULL, 0, VM_PROT_READ | VM_PROT_WRITE,
VMCMD_STACK);
return 0;
}
int
darwin_exec_setup_stack(struct lwp *l, struct exec_package *epp)
{
u_long max_stack_size;
u_long access_linear_min, access_size;
u_long noaccess_linear_min, noaccess_size;
if (epp->ep_flags & EXEC_32) {
epp->ep_minsaddr = DARWIN_USRSTACK32;
max_stack_size = MAXSSIZ;
} else {
epp->ep_minsaddr = DARWIN_USRSTACK;
max_stack_size = MAXSSIZ;
}
epp->ep_maxsaddr = (u_long)STACK_GROW(epp->ep_minsaddr,
max_stack_size);
epp->ep_ssize = l->l_proc->p_rlimit[RLIMIT_STACK].rlim_cur;
/*
* set up commands for stack. note that this takes *two*, one to
* map the part of the stack which we can access, and one to map
* the part which we can't.
*
* arguably, it could be made into one, but that would require the
* addition of another mapping proc, which is unnecessary
*/
access_size = epp->ep_ssize;
access_linear_min = (u_long)STACK_ALLOC(epp->ep_minsaddr, access_size);
noaccess_size = max_stack_size - access_size;
noaccess_linear_min = (u_long)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr,
access_size), noaccess_size);
if (noaccess_size > 0) {
NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, noaccess_size,
noaccess_linear_min, NULL, 0, VM_PROT_NONE, VMCMD_STACK);
}
KASSERT(access_size > 0);
NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, access_size,
access_linear_min, NULL, 0, VM_PROT_READ | VM_PROT_WRITE,
VMCMD_STACK);
return 0;
}
/*
* Load a psection at the appropriate address
*/
void
ELFNAME(load_psection)(struct exec_vmcmd_set *vcset, struct vnode *vp,
Elf_Phdr *ph, Elf_Addr *addr, Elf_Addr *size, int *prot, int flags)
{
u_long uaddr, msize, lsize, psize, rm, rf;
long diff, offset, bdiff;
Elf_Addr base;
/*
* If the user specified an address, then we load there.
*/
if (*addr != ELFDEFNNAME(NO_ADDR)) {
if (ph->p_align > 1) {
*addr = ELF_TRUNC(*addr, ph->p_align);
diff = ph->p_vaddr - ELF_TRUNC(ph->p_vaddr, ph->p_align);
/* page align vaddr */
base = *addr + trunc_page(ph->p_vaddr)
- ELF_TRUNC(ph->p_vaddr, ph->p_align);
bdiff = ph->p_vaddr - trunc_page(ph->p_vaddr);
} else
diff = 0;
} else {
*addr = uaddr = ph->p_vaddr;
if (ph->p_align > 1)
*addr = ELF_TRUNC(uaddr, ph->p_align);
base = trunc_page(uaddr);
bdiff = uaddr - base;
diff = uaddr - *addr;
}
*prot |= (ph->p_flags & PF_R) ? VM_PROT_READ : 0;
*prot |= (ph->p_flags & PF_W) ? VM_PROT_WRITE : 0;
*prot |= (ph->p_flags & PF_X) ? VM_PROT_EXECUTE : 0;
msize = ph->p_memsz + diff;
offset = ph->p_offset - bdiff;
lsize = ph->p_filesz + bdiff;
psize = round_page(lsize);
/*
* Because the pagedvn pager can't handle zero fill of the last
* data page if it's not page aligned we map the last page readvn.
*/
if (ph->p_flags & PF_W) {
psize = trunc_page(lsize);
if (psize > 0)
NEW_VMCMD2(vcset, vmcmd_map_pagedvn, psize, base, vp,
offset, *prot, flags);
if (psize != lsize) {
NEW_VMCMD2(vcset, vmcmd_map_readvn, lsize - psize,
base + psize, vp, offset + psize, *prot, flags);
}
} else {
NEW_VMCMD2(vcset, vmcmd_map_pagedvn, psize, base, vp, offset,
*prot, flags);
}
/*
* Check if we need to extend the size of the segment
*/
rm = round_page(*addr + ph->p_memsz + diff);
rf = round_page(*addr + ph->p_filesz + diff);
if (rm != rf) {
NEW_VMCMD2(vcset, vmcmd_map_zero, rm - rf, rf, NULLVP, 0,
*prot, flags);
}
*size = msize;
}
