From: Greg Ungerer <gerg@uclinux.org>
Date: Tue, 2 Apr 2013 04:25:33 +0000 (+1000)
Subject: romfs: fix nommu map length to keep inside filesystem
X-Git-Tag: v3.10-rc1~17^2~8
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e4ba4fc2b98f659f525d02721643a01015a8e3ed;p=pandora-kernel.git

romfs: fix nommu map length to keep inside filesystem

Checks introduced in commit 4991e7251 ("romfs: do not use
mtd->get_unmapped_area directly") re-introduce problems fixed in the earlier
commit 2b4b2482e ("romfs: fix romfs_get_unmapped_area() argument check").

If a flat binary app is located at the end of a romfs, its page aligned
length may be outside of the romfs filesystem. The flat binary loader, via
nommu do_mmap_pgoff(), page aligns the length it is mmaping. So simple
offset+size checks will fail - returning EINVAL.

We can truncate the length to keep it inside the romfs filesystem, and that
also keeps the call to mtd_get_unmapped_area() happy.

Are there any side effects to truncating the size here though?

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
---

Reading git-diff-tree failed