* Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- *
+ *
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
- *
+ *
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
- *
+ *
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
- *
+ *
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
#include <sys/user.h>
#include <sys/dtrace_ptss.h>
+#include <mach/vm_map.h>
#include <mach/vm_param.h>
#include <mach/mach_vm.h>
* page of memory, the underlying kernel _MALLOC may block.
*/
struct dtrace_ptss_page_entry*
-dtrace_ptss_claim_entry_locked(struct proc* p) {
- lck_mtx_assert(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
+dtrace_ptss_claim_entry_locked(struct proc* p)
+{
+ LCK_MTX_ASSERT(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
struct dtrace_ptss_page_entry* entry = NULL;
struct dtrace_ptss_page* page = dtrace_ptss_allocate_page(p);
// Make sure we actually got a page
- if (page == NULL)
+ if (page == NULL) {
return NULL;
+ }
// Add the page to the page list
page->next = p->p_dtrace_ptss_pages;
// CAS the entries onto the free list.
do {
- page->entries[DTRACE_PTSS_ENTRIES_PER_PAGE-1].next = p->p_dtrace_ptss_free_list;
- } while (!OSCompareAndSwapPtr((void *)page->entries[DTRACE_PTSS_ENTRIES_PER_PAGE-1].next,
- (void *)&page->entries[0],
- (void * volatile *)&p->p_dtrace_ptss_free_list));
-
+ page->entries[DTRACE_PTSS_ENTRIES_PER_PAGE - 1].next = p->p_dtrace_ptss_free_list;
+ } while (!OSCompareAndSwapPtr((void *)page->entries[DTRACE_PTSS_ENTRIES_PER_PAGE - 1].next,
+ (void *)&page->entries[0],
+ (void * volatile *)&p->p_dtrace_ptss_free_list));
+
// Now that we've added to the free list, try again.
continue;
}
// Claim temp
- if (!OSCompareAndSwapPtr((void *)temp, (void *)temp->next, (void * volatile *)&p->p_dtrace_ptss_free_list))
+ if (!OSCompareAndSwapPtr((void *)temp, (void *)temp->next, (void * volatile *)&p->p_dtrace_ptss_free_list)) {
continue;
+ }
// At this point, we own temp.
entry = temp;
* This function does not require any locks to be held on entry.
*/
struct dtrace_ptss_page_entry*
-dtrace_ptss_claim_entry(struct proc* p) {
+dtrace_ptss_claim_entry(struct proc* p)
+{
// Verify no locks held on entry
- lck_mtx_assert(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_NOTOWNED);
- lck_mtx_assert(&p->p_mlock, LCK_MTX_ASSERT_NOTOWNED);
+ LCK_MTX_ASSERT(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_NOTOWNED);
+ LCK_MTX_ASSERT(&p->p_mlock, LCK_MTX_ASSERT_NOTOWNED);
struct dtrace_ptss_page_entry* entry = NULL;
}
// Claim temp
- if (!OSCompareAndSwapPtr((void *)temp, (void *)temp->next, (void * volatile *)&p->p_dtrace_ptss_free_list))
+ if (!OSCompareAndSwapPtr((void *)temp, (void *)temp->next, (void * volatile *)&p->p_dtrace_ptss_free_list)) {
continue;
+ }
// At this point, we own temp.
entry = temp;
/*
* This function does not require any locks to be held on entry.
+ *
+ * (PR-11138709) A NULL p->p_dtrace_ptss_pages means the entry can
+ * no longer be referenced safely. When found in this state, the chore
+ * of releasing an entry to the free list is ignored.
*/
void
-dtrace_ptss_release_entry(struct proc* p, struct dtrace_ptss_page_entry* e) {
- if (p && e) {
+dtrace_ptss_release_entry(struct proc* p, struct dtrace_ptss_page_entry* e)
+{
+ if (p && p->p_dtrace_ptss_pages && e) {
do {
e->next = p->p_dtrace_ptss_free_list;
} while (!OSCompareAndSwapPtr((void *)e->next, (void *)e, (void * volatile *)&p->p_dtrace_ptss_free_list));
/*
* This function allocates a new page in the target process's address space.
- *
+ *
* It returns a dtrace_ptss_page that has its entries chained, with the last
* entries next field set to NULL. It does not add the page or the entries to
* the process's page/entry lists.
{
// Allocate the kernel side data
struct dtrace_ptss_page* ptss_page = _MALLOC(sizeof(struct dtrace_ptss_page), M_TEMP, M_ZERO | M_WAITOK);
- if (ptss_page == NULL)
+ if (ptss_page == NULL) {
return NULL;
+ }
// Now allocate a page in user space and set its protections to allow execute.
task_t task = p->task;
vm_map_t map = get_task_map_reference(task);
+ if (map == NULL) {
+ goto err;
+ }
- mach_vm_address_t addr = 0LL;
- mach_vm_size_t size = PAGE_SIZE; // We need some way to assert that this matches vm_map_round_page() !!!
+ mach_vm_size_t size = PAGE_MAX_SIZE;
+ mach_vm_offset_t addr = 0;
+ mach_vm_offset_t write_addr = 0;
+ /*
+ * The embedded OS has extra permissions for writable and executable pages.
+ * To ensure correct permissions, we must set the page protections separately.
+ */
+ vm_prot_t cur_protection = VM_PROT_READ | VM_PROT_EXECUTE;
+ vm_prot_t max_protection = VM_PROT_READ | VM_PROT_EXECUTE | VM_PROT_WRITE;
-#if CONFIG_EMBEDDED
- /* The embedded OS has extra permissions for writable and executable pages. We can't pass in the flags
- * we need for the correct permissions from mach_vm_allocate, so need to call mach_vm_map directly. */
- vm_map_offset_t map_addr = 0;
- kern_return_t kr = mach_vm_map(map, &map_addr, size, 0, VM_FLAGS_ANYWHERE, IPC_PORT_NULL, 0, FALSE, VM_PROT_READ|VM_PROT_EXECUTE, VM_PROT_READ|VM_PROT_EXECUTE, VM_INHERIT_DEFAULT);
+ kern_return_t kr = mach_vm_map_kernel(map, &addr, size, 0, VM_FLAGS_ANYWHERE, VM_MAP_KERNEL_FLAGS_NONE, VM_KERN_MEMORY_NONE, IPC_PORT_NULL, 0, FALSE, cur_protection, max_protection, VM_INHERIT_DEFAULT);
if (kr != KERN_SUCCESS) {
goto err;
}
- addr = map_addr;
-#else
- kern_return_t kr = mach_vm_allocate(map, &addr, size, VM_FLAGS_ANYWHERE);
- if (kr != KERN_SUCCESS) {
+ /*
+ * If on embedded, remap the scratch space as writable at another
+ * virtual address
+ */
+ kr = mach_vm_remap_kernel(map, &write_addr, size, 0, VM_FLAGS_ANYWHERE, VM_KERN_MEMORY_NONE, map, addr, FALSE, &cur_protection, &max_protection, VM_INHERIT_DEFAULT);
+ if (kr != KERN_SUCCESS || !(max_protection & VM_PROT_WRITE)) {
goto err;
}
- kr = mach_vm_protect(map, addr, size, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
+ kr = mach_vm_protect(map, (mach_vm_offset_t)write_addr, (mach_vm_size_t)size, 0, VM_PROT_READ | VM_PROT_WRITE);
if (kr != KERN_SUCCESS) {
- mach_vm_deallocate(map, addr, size);
goto err;
- }
-#endif
+ }
// Chain the page entries.
int i;
- for (i=0; i<DTRACE_PTSS_ENTRIES_PER_PAGE; i++) {
+ for (i = 0; i < DTRACE_PTSS_ENTRIES_PER_PAGE; i++) {
ptss_page->entries[i].addr = addr + (i * DTRACE_PTSS_SCRATCH_SPACE_PER_THREAD);
- ptss_page->entries[i].next = &ptss_page->entries[i+1];
+ ptss_page->entries[i].write_addr = write_addr + (i * DTRACE_PTSS_SCRATCH_SPACE_PER_THREAD);
+ ptss_page->entries[i].next = &ptss_page->entries[i + 1];
}
// The last entry should point to NULL
- ptss_page->entries[DTRACE_PTSS_ENTRIES_PER_PAGE-1].next = NULL;
+ ptss_page->entries[DTRACE_PTSS_ENTRIES_PER_PAGE - 1].next = NULL;
vm_map_deallocate(map);
err:
_FREE(ptss_page, M_TEMP);
- vm_map_deallocate(map);
+ if (map) {
+ vm_map_deallocate(map);
+ }
return NULL;
}
/*
* This function frees an existing page in the target process's address space.
- *
+ *
* It does not alter any of the process's page/entry lists.
*
* TODO: Inline in dtrace_ptrace_exec_exit?
// Silent failures, no point in checking return code.
mach_vm_deallocate(map, addr, size);
+ mach_vm_address_t write_addr = ptss_page->entries[0].write_addr;
+ mach_vm_deallocate(map, write_addr, size);
+
vm_map_deallocate(map);
}
/*
* This function assumes that the target process has been
- * suspended, and the proc_lock & sprlock is held
+ * suspended, and the proc_lock & sprlock is held
*/
void
-dtrace_ptss_enable(struct proc* p) {
- lck_mtx_assert(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
- lck_mtx_assert(&p->p_mlock, LCK_MTX_ASSERT_OWNED);
+dtrace_ptss_enable(struct proc* p)
+{
+ LCK_MTX_ASSERT(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
+ LCK_MTX_ASSERT(&p->p_mlock, LCK_MTX_ASSERT_OWNED);
struct uthread* uth;
/*
* It assumes the sprlock is held, and the proc_lock is not.
*/
void
-dtrace_ptss_exec_exit(struct proc* p) {
+dtrace_ptss_exec_exit(struct proc* p)
+{
/*
* Should hold sprlock to touch the pages list. Must not
* hold the proc lock to avoid deadlock.
*/
- lck_mtx_assert(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
- lck_mtx_assert(&p->p_mlock, LCK_MTX_ASSERT_NOTOWNED);
+ LCK_MTX_ASSERT(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
+ LCK_MTX_ASSERT(&p->p_mlock, LCK_MTX_ASSERT_NOTOWNED);
p->p_dtrace_ptss_free_list = NULL;
while (temp != NULL) {
struct dtrace_ptss_page* next = temp->next;
-
+
// Do we need to specifically mach_vm_deallocate the user pages?
// This can be called when the process is exiting, I believe the proc's
// vm_map_t may already be toast.
-
+
// Must be certain to free the kernel memory!
_FREE(temp, M_TEMP);
temp = next;
* Parent and child sprlock should be held, and proc_lock must NOT be held.
*/
void
-dtrace_ptss_fork(struct proc* parent, struct proc* child) {
+dtrace_ptss_fork(struct proc* parent, struct proc* child)
+{
// The child should not have any pages/entries allocated at this point.
// ASSERT(child->p_dtrace_ptss_pages == NULL);
// ASSERT(child->p_dtrace_ptss_free_list == NULL);
* Finally, to prevent a deadlock with the fasttrap cleanup code,
* neither the parent or child proc_lock should be held.
*/
- lck_mtx_assert(&parent->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
- lck_mtx_assert(&parent->p_mlock, LCK_MTX_ASSERT_NOTOWNED);
- lck_mtx_assert(&child->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
- lck_mtx_assert(&child->p_mlock, LCK_MTX_ASSERT_NOTOWNED);
+ LCK_MTX_ASSERT(&parent->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
+ LCK_MTX_ASSERT(&parent->p_mlock, LCK_MTX_ASSERT_NOTOWNED);
+ LCK_MTX_ASSERT(&child->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
+ LCK_MTX_ASSERT(&child->p_mlock, LCK_MTX_ASSERT_NOTOWNED);
// Get page list from *PARENT*
struct dtrace_ptss_page* temp = parent->p_dtrace_ptss_pages;
- while (temp != NULL) {
+ while (temp != NULL) {
// Freeing the page in the *CHILD*
dtrace_ptss_free_page(child, temp);
projects / apple / xnu.git / blobdiff