#include <linux/module.h>
#include <linux/kallsyms.h>
#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/random.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/i387.h>
#include <asm/irq.h>
#include <asm/desc.h>
+#include <asm/atomic_kmap.h>
#ifdef CONFIG_MATH_EMULATION
#include <asm/math_emu.h>
#endif
if (!strncmp(str, "poll", 4)) {
printk("using polling idle threads.\n");
pm_idle = poll_idle;
+#ifdef CONFIG_SMP
+ if (smp_num_siblings > 1)
+ printk("WARNING: polling idle and HT enabled, performance may degrade.\n");
+#endif
} else if (!strncmp(str, "halt", 4)) {
printk("using halt in idle threads.\n");
pm_idle = default_idle;
struct task_struct *tsk = current;
memset(tsk->thread.debugreg, 0, sizeof(unsigned long)*8);
+#ifdef CONFIG_X86_HIGH_ENTRY
+ clear_thread_flag(TIF_DB7);
+#endif
memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array));
/*
* Forget coprocessor state..
if (dead_task->mm) {
// temporary debugging check
if (dead_task->mm->context.size) {
- printk("WARNING: dead process %8s still has LDT? <%p/%d>\n",
+ printk("WARNING: dead process %8s still has LDT? <%d>\n",
dead_task->comm,
- dead_task->mm->context.ldt,
dead_task->mm->context.size);
BUG();
}
{
struct pt_regs * childregs;
struct task_struct *tsk;
- int err;
+ int err, i;
childregs = ((struct pt_regs *) (THREAD_SIZE + (unsigned long) p->thread_info)) - 1;
struct_cpy(childregs, regs);
p->thread.esp = (unsigned long) childregs;
p->thread.esp0 = (unsigned long) (childregs+1);
+ /*
+ * get the two stack pages, for the virtual stack.
+ *
+ * IMPORTANT: this code relies on the fact that the task
+ * structure is an THREAD_SIZE aligned piece of physical memory.
+ */
+ for (i = 0; i < ARRAY_SIZE(p->thread.stack_page); i++)
+ p->thread.stack_page[i] =
+ virt_to_page((unsigned long)p->thread_info + (i*PAGE_SIZE));
+
p->thread.eip = (unsigned long) ret_from_fork;
+ p->thread_info->real_stack = p->thread_info;
savesegment(fs,p->thread.fs);
savesegment(gs,p->thread.gs);
/* never put a printk in __switch_to... printk() calls wake_up*() indirectly */
__unlazy_fpu(prev_p);
+ if (next_p->mm)
+ load_user_cs_desc(cpu, next_p->mm);
+#ifdef CONFIG_X86_HIGH_ENTRY
+{
+ int i;
+ /*
+ * Set the ptes of the virtual stack. (NOTE: a one-page TLB flush is
+ * needed because otherwise NMIs could interrupt the
+ * user-return code with a virtual stack and stale TLBs.)
+ */
+ for (i = 0; i < ARRAY_SIZE(next->stack_page); i++) {
+ __kunmap_atomic_type(KM_VSTACK_TOP-i);
+ __kmap_atomic(next->stack_page[i], KM_VSTACK_TOP-i);
+ }
+ /*
+ * NOTE: here we rely on the task being the stack as well
+ */
+ next_p->thread_info->virtual_stack =
+ (void *)__kmap_atomic_vaddr(KM_VSTACK_TOP);
+}
+#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
+ /*
+ * If next was preempted on entry from userspace to kernel,
+ * and now it's on a different cpu, we need to adjust %esp.
+ * This assumes that entry.S does not copy %esp while on the
+ * virtual stack (with interrupts enabled): which is so,
+ * except within __SWITCH_KERNELSPACE itself.
+ */
+ if (unlikely(next->esp >= TASK_SIZE)) {
+ next->esp &= THREAD_SIZE - 1;
+ next->esp |= (unsigned long) next_p->thread_info->virtual_stack;
+ }
+#endif
+#endif
/*
* Reload esp0, LDT and the page table pointer:
*/
- load_esp0(tss, next);
+ load_virtual_esp0(tss, next_p);
/*
* Load the per-thread Thread-Local Storage descriptor.
return error;
}
-/*
- * These bracket the sleeping functions..
- */
-#define first_sched ((unsigned long) scheduling_functions_start_here)
-#define last_sched ((unsigned long) scheduling_functions_end_here)
#define top_esp (THREAD_SIZE - sizeof(unsigned long))
#define top_ebp (THREAD_SIZE - 2*sizeof(unsigned long))
if (ebp < stack_page || ebp > top_ebp+stack_page)
return 0;
eip = *(unsigned long *) (ebp+4);
- if (eip < first_sched || eip >= last_sched)
+ if (!in_sched_functions(eip))
return eip;
ebp = *(unsigned long *) ebp;
} while (count++ < 16);
return 0;
}
-#undef last_sched
-#undef first_sched
/*
* sys_alloc_thread_area: get a yet unused TLS descriptor index.
((desc)->a & 0x0ffff) | \
((desc)->b & 0xf0000) )
-#define GET_32BIT(desc) (((desc)->b >> 23) & 1)
+#define GET_32BIT(desc) (((desc)->b >> 22) & 1)
#define GET_CONTENTS(desc) (((desc)->b >> 10) & 3)
#define GET_WRITABLE(desc) (((desc)->b >> 9) & 1)
#define GET_LIMIT_PAGES(desc) (((desc)->b >> 23) & 1)
return 0;
}
+/*
+ * Get a random word:
+ */
+static inline unsigned int get_random_int(void)
+{
+ unsigned int val = 0;
+
+ if (!exec_shield_randomize)
+ return 0;
+
+#ifdef CONFIG_X86_HAS_TSC
+ rdtscl(val);
+#endif
+ val += current->pid + jiffies + (int)&val;
+
+ /*
+ * Use IP's RNG. It suits our purpose perfectly: it re-keys itself
+ * every second, from the entropy pool (and thus creates a limited
+ * drain on it), and uses halfMD4Transform within the second. We
+ * also spice it with the TSC (if available), jiffies, PID and the
+ * stack address:
+ */
+ return secure_ip_id(val);
+}
+
+unsigned long arch_align_stack(unsigned long sp)
+{
+ if (current->flags & PF_RELOCEXEC)
+ sp -= ((get_random_int() % 65536) << 4);
+ return sp & ~0xf;
+}
+
+#if SHLIB_BASE >= 0x01000000
+# error SHLIB_BASE must be under 16MB!
+#endif
+
+static unsigned long
+arch_get_unmapped_nonexecutable_area(struct mm_struct *mm, unsigned long addr, unsigned long len)
+{
+ struct vm_area_struct *vma, *prev_vma;
+ unsigned long stack_limit;
+ int first_time = 1;
+
+ if (!mm->mmap_top) {
+ printk("hm, %s:%d, !mmap_top.\n", current->comm, current->pid);
+ mm->mmap_top = mmap_top();
+ }
+ stack_limit = mm->mmap_top;
+
+ /* requested length too big for entire address space */
+ if (len > TASK_SIZE)
+ return -ENOMEM;
+
+ /* dont allow allocations above current stack limit */
+ if (mm->non_executable_cache > stack_limit)
+ mm->non_executable_cache = stack_limit;
+
+ /* requesting a specific address */
+ if (addr) {
+ addr = PAGE_ALIGN(addr);
+ vma = find_vma(mm, addr);
+ if (TASK_SIZE - len >= addr &&
+ (!vma || addr + len <= vma->vm_start))
+ return addr;
+ }
+
+ /* make sure it can fit in the remaining address space */
+ if (mm->non_executable_cache < len)
+ return -ENOMEM;
+
+ /* either no address requested or cant fit in requested address hole */
+try_again:
+ addr = (mm->non_executable_cache - len)&PAGE_MASK;
+ do {
+ if (!(vma = find_vma_prev(mm, addr, &prev_vma)))
+ return -ENOMEM;
+
+ /* new region fits between prev_vma->vm_end and vma->vm_start, use it */
+ if (addr+len <= vma->vm_start && (!prev_vma || (addr >= prev_vma->vm_end))) {
+ /* remember the address as a hint for next time */
+ mm->non_executable_cache = addr;
+ return addr;
+
+ /* pull non_executable_cache down to the first hole */
+ } else if (mm->non_executable_cache == vma->vm_end)
+ mm->non_executable_cache = vma->vm_start;
+
+ /* try just below the current vma->vm_start */
+ addr = vma->vm_start-len;
+ } while (len <= vma->vm_start);
+ /* if hint left us with no space for the requested mapping try again */
+ if (first_time) {
+ first_time = 0;
+ mm->non_executable_cache = stack_limit;
+ goto try_again;
+ }
+ return -ENOMEM;
+}
+
+static unsigned long randomize_range(unsigned long start, unsigned long end, unsigned long len)
+{
+ unsigned long range = end - len - start;
+ if (end <= start + len)
+ return 0;
+ return PAGE_ALIGN(get_random_int() % range + start);
+}
+
+static inline unsigned long
+stock_arch_get_unmapped_area(struct file *filp, unsigned long addr,
+ unsigned long len, unsigned long pgoff, unsigned long flags)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ unsigned long start_addr;
+
+ if (len > TASK_SIZE)
+ return -ENOMEM;
+
+ if (addr) {
+ addr = PAGE_ALIGN(addr);
+ vma = find_vma(mm, addr);
+ if (TASK_SIZE - len >= addr &&
+ (!vma || addr + len <= vma->vm_start))
+ return addr;
+ }
+ start_addr = addr = mm->free_area_cache;
+
+full_search:
+ for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
+ /* At this point: (!vma || addr < vma->vm_end). */
+ if (TASK_SIZE - len < addr) {
+ /*
+ * Start a new search - just in case we missed
+ * some holes.
+ */
+ if (start_addr != TASK_UNMAPPED_BASE) {
+ start_addr = addr = TASK_UNMAPPED_BASE;
+ goto full_search;
+ }
+ return -ENOMEM;
+ }
+ if (!vma || addr + len <= vma->vm_start) {
+ /*
+ * Remember the place where we stopped the search:
+ */
+ mm->free_area_cache = addr + len;
+ return addr;
+ }
+ addr = vma->vm_end;
+ }
+}
+
+unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr0,
+ unsigned long len0, unsigned long pgoff, unsigned long flags,
+ unsigned long prot)
+{
+ unsigned long addr = addr0, len = len0;
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ int ascii_shield = 0;
+ unsigned long tmp;
+
+ /*
+ * Fall back to the old layout:
+ */
+ if (!(current->flags & PF_RELOCEXEC))
+ return stock_arch_get_unmapped_area(filp, addr0, len0, pgoff, flags);
+ if (len > TASK_SIZE)
+ return -ENOMEM;
+
+ if (!addr && (prot & PROT_EXEC) && !(flags & MAP_FIXED))
+ addr = randomize_range(SHLIB_BASE, 0x01000000, len);
+
+ if (addr) {
+ addr = PAGE_ALIGN(addr);
+ vma = find_vma(mm, addr);
+ if (TASK_SIZE - len >= addr &&
+ (!vma || addr + len <= vma->vm_start)) {
+ return addr;
+ }
+ }
+
+ if (prot & PROT_EXEC) {
+ ascii_shield = 1;
+ addr = SHLIB_BASE;
+ } else {
+ /* this can fail if the stack was unlimited */
+ if ((tmp = arch_get_unmapped_nonexecutable_area(mm, addr, len)) != -ENOMEM)
+ return tmp;
+search_upper:
+ addr = PAGE_ALIGN(arch_align_stack(TASK_UNMAPPED_BASE));
+ }
+
+ for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
+ /* At this point: (!vma || addr < vma->vm_end). */
+ if (TASK_SIZE - len < addr) {
+ return -ENOMEM;
+ }
+ if (!vma || addr + len <= vma->vm_start) {
+ /*
+ * Must not let a PROT_EXEC mapping get into the
+ * brk area:
+ */
+ if (ascii_shield && (addr + len > mm->brk)) {
+ ascii_shield = 0;
+ goto search_upper;
+ }
+ /*
+ * Up until the brk area we randomize addresses
+ * as much as possible:
+ */
+ if (ascii_shield && (addr >= 0x01000000)) {
+ tmp = randomize_range(0x01000000, mm->brk, len);
+ vma = find_vma(mm, tmp);
+ if (TASK_SIZE - len >= tmp &&
+ (!vma || tmp + len <= vma->vm_start))
+ return tmp;
+ }
+ /*
+ * Ok, randomization didnt work out - return
+ * the result of the linear search:
+ */
+ return addr;
+ }
+ addr = vma->vm_end;
+ }
+}
+
+void arch_add_exec_range(struct mm_struct *mm, unsigned long limit)
+{
+ if (limit > mm->context.exec_limit) {
+ mm->context.exec_limit = limit;
+ set_user_cs(&mm->context.user_cs, limit);
+ if (mm == current->mm)
+ load_user_cs_desc(smp_processor_id(), mm);
+ }
+}
+
+void arch_remove_exec_range(struct mm_struct *mm, unsigned long old_end)
+{
+ struct vm_area_struct *vma;
+ unsigned long limit = 0;
+
+ if (old_end == mm->context.exec_limit) {
+ for (vma = mm->mmap; vma; vma = vma->vm_next)
+ if ((vma->vm_flags & VM_EXEC) && (vma->vm_end > limit))
+ limit = vma->vm_end;
+
+ mm->context.exec_limit = limit;
+ set_user_cs(&mm->context.user_cs, limit);
+ if (mm == current->mm)
+ load_user_cs_desc(smp_processor_id(), mm);
+ }
+}
+
+void arch_flush_exec_range(struct mm_struct *mm)
+{
+ mm->context.exec_limit = 0;
+ set_user_cs(&mm->context.user_cs, 0);
+}
+
+/*
+ * Generate random brk address between 128MB and 196MB. (if the layout
+ * allows it.)
+ */
+void randomize_brk(unsigned long old_brk)
+{
+ unsigned long new_brk, range_start, range_end;
+
+ range_start = 0x08000000;
+ if (current->mm->brk >= range_start)
+ range_start = current->mm->brk;
+ range_end = range_start + 0x02000000;
+ new_brk = randomize_range(range_start, range_end, 0);
+ if (new_brk)
+ current->mm->brk = new_brk;
+}
+
+/*
+ * Top of mmap area (just below the process stack).
+ * leave an at least ~128 MB hole. Randomize it.
+ */
+#define MIN_GAP (128*1024*1024)
+#define MAX_GAP (TASK_SIZE/6*5)
+
+unsigned long mmap_top(void)
+{
+ unsigned long gap = 0;
+
+ gap = current->rlim[RLIMIT_STACK].rlim_cur;
+ if (gap < MIN_GAP)
+ gap = MIN_GAP;
+ else if (gap > MAX_GAP)
+ gap = MAX_GAP;
+
+ gap = arch_align_stack(gap) & PAGE_MASK;
+
+ return TASK_SIZE - gap;
+}
+
git://git.onelab.eu / linux-2.6.git / blobdiff