[PATCH][TRIVIAL] mmap.c corner case fix

[DervishD <raul@pleyades.net>]

[-- Attachment #1: Type: text/plain, Size: 399 bytes --]

    Hi Marcelo :)

    This patch fixes a corner case on the mmap() syscall.

    The patch is from David S. Miller, not me. My patch was
incomplete and did nothing on 'big TASK_SIZE' architectures.

    The patch is against both 2.4.20 and 2.4.21-pre, is just the same.
Please apply. I sent you the incomplete patch at pre-1 and this bug
is getting older by the minute ;))

    Thanks :)

    Raúl

[-- Attachment #2: mmap.c.diff for 2.4.20 and 2.4.21-pre --]
[-- Type: text/plain, Size: 407 bytes --]

--- linux/mm/mmap.c.orig	2002-12-11 13:59:37.000000000 +0100
+++ linux/mm/mmap.c	2002-12-11 14:01:16.000000000 +0100
@@ -403,10 +403,12 @@
 	if (file && (!file->f_op || !file->f_op->mmap))
 		return -ENODEV;
 
-	if ((len = PAGE_ALIGN(len)) == 0)
+	if (!len)
 		return addr;
 
-	if (len > TASK_SIZE)
+	len = PAGE_ALIGN(len);
+
+	if (len > TASK_SIZE || len == 0)
 		return -EINVAL;
 
 	/* offset overflow? */