2011-06-14 05:26:53

by Bob Liu

[permalink] [raw]
Subject: [PATCH] romfs: fix romfs_get_unmapped_area() param check

romfs_get_unmapped_area() check param len without considering PAGE_ALIGN which
will cause do_mmap_pgoff() return -EINVAL error after commit f67d9b1576c
nommu: add page_align to mmap.

This patch fix the param check by changing it to the same way which function
ramfs_nommu_get_unmapped_area() did in ramfs/file-nommu.c.

Signed-off-by: Bob Liu <[email protected]>
---
fs/romfs/mmap-nommu.c | 8 ++++++--
1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/romfs/mmap-nommu.c b/fs/romfs/mmap-nommu.c
index f0511e8..eed9942 100644
--- a/fs/romfs/mmap-nommu.c
+++ b/fs/romfs/mmap-nommu.c
@@ -27,14 +27,18 @@ static unsigned long romfs_get_unmapped_area(struct file *file,
{
struct inode *inode = file->f_mapping->host;
struct mtd_info *mtd = inode->i_sb->s_mtd;
- unsigned long isize, offset;
+ unsigned long isize, offset, maxpages, lpages;

if (!mtd)
goto cant_map_directly;

+ /* the mapping mustn't extend beyond the EOF */
+ lpages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
isize = i_size_read(inode);
offset = pgoff << PAGE_SHIFT;
- if (offset > isize || len > isize || offset > isize - len)
+
+ maxpages = (isize + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ if ((pgoff >= maxpages) || (maxpages - pgoff < lpages))
return (unsigned long) -EINVAL;

/* we need to call down to the MTD layer to do the actual mapping */
--
1.6.3.3