[PATCH 4.14 28/77] fuse: fix writepages on 32bit

Greg Kroah-Hartman
2019-05-23T19:11:33Z

From: Miklos Szeredi <mszeredi@redhat.com>

commit 9de5be06d0a89ca97b5ab902694d42dfd2bb77d2 upstream.

Writepage requests were cropped to i_size & 0xffffffff, which meant that
mmaped writes to any file larger than 4G might be silently discarded.

Fix by storing the file size in a properly sized variable (loff_t instead
of size_t).

Reported-by: Antonio SJ Musumeci <trapexit@spawn.link>
Fixes: 6eaf4782eb09 ("fuse: writepages: crop secondary requests")
Cc: <stable@vger.kernel.org> # v3.13
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/fuse/file.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1525,7 +1525,7 @@ __acquires(fc->lock)
{
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_inode *fi = get_fuse_inode(inode);
- size_t crop = i_size_read(inode);
+ loff_t crop = i_size_read(inode);
struct fuse_req *req;

while (fi->writectr >= 0 && !list_empty(&fi->queued_writes)) {