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Subject[PATCH] mmap.c (do_mmap_pgoff) 'repatched'.
    Hi Alan :))

The patch I sent you for mmap.c, correcting a corner case,
namely the case where the requested size on a call to 'mmap()' was
greater than SIZE_MAX-PAGE_SIZE, because the size was incorrectly
page-aligned to size '0', does nothing if TASK_SIZE is the full
address space for the task. This happens, for example, under sparc64.

This new patch covers this case and works even if TASK_SIZE is
very huge. My patch was completed by David S. Miller <davem@redhat.com>
and now should work for all cases.

The patch is against your 2.4.20-ac1 tree. If you have any doubt,
please tell.

Thanks ;)

Raúl
--- linux/mm/mmap.c.orig 2002-12-11 14:08:39.000000000 +0100
+++ linux/mm/mmap.c 2002-12-11 14:09:54.000000000 +0100
@@ -473,10 +473,6 @@
}


-/*
- * NOTE: in this function we rely on TASK_SIZE being lower than
- * SIZE_MAX-PAGE_SIZE at least. I'm pretty sure that it is.
- */

unsigned long do_mmap_pgoff(struct file * file, unsigned long addr, unsigned long len,
unsigned long prot, unsigned long flags, unsigned long pgoff)
@@ -493,14 +489,14 @@
if (file && (!file->f_op || !file->f_op->mmap))
return -ENODEV;

- if (!len)
+ if (len == 0)
return addr;
+
+ len = PAGE_ALIGN(len);

- if (len > TASK_SIZE)
+ if (len > TASK_SIZE || len == 0)
return -EINVAL;

- len = PAGE_ALIGN(len); /* This cannot be zero now */
-
/* offset overflow? */
if ((pgoff + (len >> PAGE_SHIFT)) < pgoff)
return -EINVAL;
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