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Separate mmap area from program loading (relocation) area

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We need to separate the two because the heap of a PIE is created in
the area to which it is mapped.

Related commits:

b1309a5d: PIE is mapped at map_end instead of at
          user_start
c4219655: Interpreter is mapped to map_start to make a
          system call that dereferences a NULL pointer fail

[dominique.martinet@cea.fr: Also add ULONG_MAX and friend macroes,
 used for data_min]
[ken.sato.ty@hitachi-solutions.com: fix execve]
Change-Id: I8ecaf22b7965090ab67bebece57c68283ba23664
This commit is contained in:
Masamichi Takagi
2019-01-15 09:48:28 +00:00
committed by Dominique Martinet
parent 97e0219f50
commit 4d215de641
5 changed files with 31 additions and 19 deletions
Download Patch File Download Diff File Expand all files Collapse all files

32
kernel/host.c
View File

@ -98,6 +98,7 @@ int prepare_process_ranges_args_envs(struct thread *thread,
n = p->num_sections;
vm->region.data_start = ULONG_MAX;
aout_base = (pn->reloc)? vm->region.map_end: 0;
for (i = 0; i < n; i++) {
ap_flags = 0;
@ -172,18 +173,13 @@ int prepare_process_ranges_args_envs(struct thread *thread,
p->sections[i].remote_pa = up;
/* TODO: Maybe we need flag */
if (pn->sections[i].interp) {
vm->region.map_end = e;
}
else if (i == 0) {
else if (pn->sections[i].prot & PROT_EXEC) {
vm->region.text_start = s;
vm->region.text_end = e;
}
else if (i == 1) {
vm->region.data_start = s;
vm->region.data_end = e;
}
else {
vm->region.data_start =
(s < vm->region.data_start ?
@ -212,9 +208,16 @@ int prepare_process_ranges_args_envs(struct thread *thread,
pn->at_entry += aout_base;
}
vm->region.map_start = vm->region.map_end = TASK_UNMAPPED_BASE;
vm->region.brk_start = vm->region.brk_end =
(vm->region.data_end + LARGE_PAGE_SIZE - 1) & LARGE_PAGE_MASK;
if (vm->region.brk_start >= vm->region.map_start) {
kprintf("%s: ERROR: data section is too large (end addr: %lx)\n",
__func__, vm->region.data_end);
}
#if 0
{
void *heap;
@ -528,17 +531,12 @@ static int process_msg_prepare_process(unsigned long rphys)
vm->region.user_end = pn->user_end;
if(vm->region.user_end > USER_END)
vm->region.user_end = USER_END;
if(vm->region.user_start != 0UL ||
vm->region.user_end < TASK_UNMAPPED_BASE){
vm->region.map_start =
(vm->region.user_start +
(vm->region.user_end - vm->region.user_start) / 3) &
LARGE_PAGE_MASK;
}
else{
vm->region.map_start = TASK_UNMAPPED_BASE;
}
vm->region.map_end = vm->region.map_start;
/* map_start / map_end is used to track memory area
* to which the program is loaded
*/
vm->region.map_start = vm->region.map_end = LD_TASK_UNMAPPED_BASE;
memcpy(proc->rlimit, pn->rlimit, sizeof(struct rlimit) * MCK_RLIM_MAX);
dkprintf("%s: rlim_cur: %ld, rlim_max: %ld, stack_premap: %ld\n",
__FUNCTION__,

5
kernel/syscall.c
View File

@ -2598,6 +2598,11 @@ SYSCALL_DECLARE(execve)
((char *)thread) +
KERNEL_STACK_NR_PAGES * PAGE_SIZE, desc->entry, 0);
/* map_start / map_end is used to track memory area
* to which the program is loaded
*/
vm->region.map_start = vm->region.map_end = LD_TASK_UNMAPPED_BASE;
/* Create virtual memory ranges and update args/envs */
if (prepare_process_ranges_args_envs(thread, desc, desc,
PTATTR_NO_EXECUTE | PTATTR_WRITABLE | PTATTR_FOR_USER,