[PATCH] mmap can return incorrect errno

mmap currently sets errno to EINVAL when it should be ENOMEM.
SUS/POSIX states that ENOMEM should be returned when:

"MAP_FIXED was specified, and the range [addr, addr + len) exceeds
that allowed for the address space of a process; or if MAP_FIXED was
not specified and there is insufficient room in the address space to
effect the mapping."

The following patch (against 2.4.17) fixes this behaviour:

mm/mmap.c

@@ -620,7 +620,7 @@ unsigned long get_unmapped_area(struct file *file, unsigned long addr, unsigned
 {
 	if (flags & MAP_FIXED) {
 		if (addr > TASK_SIZE - len)
-			return -EINVAL;
+			return -ENOMEM;
 		if (addr & ~PAGE_MASK)
 			return -EINVAL;
 		return addr;