Commit 66aa2b4b authored by Greg Ungerer's avatar Greg Ungerer Committed by Linus Torvalds
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[PATCH] uclinux: add NULL check, 0 end valid check and some more exports to nommu.c 



Move call to get_mm_counter() in update_mem_hiwater() to be
inside the check for tsk->mm being null. Otherwise you can be
following a null pointer here. This patch submitted by
Javier Herrero <jherrero@hvsistemas.es>.

Modify the end check for munmap regions to allow for the
legacy behavior of 0 being valid. Pretty much all current
uClinux system libc malloc's pass in 0 as the end point.
A hard check will fail on these, so change the check so
that if it is non-zero it must be valid otherwise it fails.
A passed in value will always succeed (as it used too).

Also export a few more mm system functions - to be consistent
with the VM code exports.

Signed-off-by: default avatarGreg Ungerer <gerg@uclinux.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 966cdb2f

mm/nommu.c

+13 −4
Original line number Diff line number Diff line
@@ -57,6 +57,11 @@ DECLARE_RWSEM(nommu_vma_sem); 
struct vm_operations_struct generic_file_vm_ops = {

};



EXPORT_SYMBOL(vmalloc);

EXPORT_SYMBOL(vfree);

EXPORT_SYMBOL(vmalloc_to_page);

EXPORT_SYMBOL(vmalloc_32);



/*

 * Handle all mappings that got truncated by a "truncate()"

 * system call.
@@ -142,6 +147,8 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, 
	return(i);

}



EXPORT_SYMBOL(get_user_pages);



DEFINE_RWLOCK(vmlist_lock);

struct vm_struct *vmlist;
@@ -852,7 +859,7 @@ unsigned long do_mmap_pgoff(struct file *file, 
 error_getting_vma:

	up_write(&nommu_vma_sem);

	kfree(vml);

	printk("Allocation of vml for %lu byte allocation from process %d failed\n",

	printk("Allocation of vma for %lu byte allocation from process %d failed\n",

	       len, current->pid);

	show_free_areas();

	return -ENOMEM;
@@ -909,7 +916,7 @@ int do_munmap(struct mm_struct *mm, unsigned long addr, size_t len) 


	for (parent = &mm->context.vmlist; *parent; parent = &(*parent)->next)

		if ((*parent)->vma->vm_start == addr &&

		    (*parent)->vma->vm_end == end)

		    ((len == 0) || ((*parent)->vma->vm_end == end)))

			goto found;



	printk("munmap of non-mmaped memory by process %d (%s): %p\n",
@@ -1054,7 +1061,8 @@ struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr) 
int remap_pfn_range(struct vm_area_struct *vma, unsigned long from,

		unsigned long to, unsigned long size, pgprot_t prot)

{

	return -EPERM;

	vma->vm_start = vma->vm_pgoff << PAGE_SHIFT;

	return 0;

}



void swap_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
@@ -1073,9 +1081,10 @@ void arch_unmap_area(struct mm_struct *mm, unsigned long addr) 


void update_mem_hiwater(struct task_struct *tsk)

{

	unsigned long rss = get_mm_counter(tsk->mm, rss);

	unsigned long rss;



	if (likely(tsk->mm)) {

		rss = get_mm_counter(tsk->mm, rss);

		if (tsk->mm->hiwater_rss < rss)

			tsk->mm->hiwater_rss = rss;

		if (tsk->mm->hiwater_vm < tsk->mm->total_vm)

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