Commit 07ab67c8 authored by Linus Torvalds's avatar Linus Torvalds

Fix get_unmapped_area sanity tests

As noted by Chris Wright, we need to do the full range of tests regardless
of whether MAP_FIXED is set or not, so re-organize get_unmapped_area()
slightly to do the sanity checks unconditionally.
parent 66e60f92
......@@ -13,6 +13,8 @@
* This should be a per-architecture thing, to allow different
* error and pointer decisions.
*/
#define IS_ERR_VALUE(x) unlikely((x) > (unsigned long)-1000L)
static inline void *ERR_PTR(long error)
{
return (void *) error;
......@@ -25,7 +27,7 @@ static inline long PTR_ERR(const void *ptr)
static inline long IS_ERR(const void *ptr)
{
return unlikely((unsigned long)ptr > (unsigned long)-1000L);
return IS_ERR_VALUE((unsigned long)ptr);
}
#endif /* _LINUX_ERR_H */
......@@ -1302,9 +1302,19 @@ unsigned long
get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
unsigned long pgoff, unsigned long flags)
{
if (flags & MAP_FIXED) {
unsigned long ret;
if (!(flags & MAP_FIXED)) {
unsigned long (*get_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
get_area = current->mm->get_unmapped_area;
if (file && file->f_op && file->f_op->get_unmapped_area)
get_area = file->f_op->get_unmapped_area;
addr = get_area(file, addr, len, pgoff, flags);
if (IS_ERR_VALUE(addr))
return addr;
}
if (addr > TASK_SIZE - len)
return -ENOMEM;
if (addr & ~PAGE_MASK)
......@@ -1326,13 +1336,6 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
if (ret)
return -EINVAL;
return addr;
}
if (file && file->f_op && file->f_op->get_unmapped_area)
return file->f_op->get_unmapped_area(file, addr, len,
pgoff, flags);
return current->mm->get_unmapped_area(file, addr, len, pgoff, flags);
}
EXPORT_SYMBOL(get_unmapped_area);
......
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