From d4e8e135a9af7d8d939bba1874ab314322fc2dc2 Mon Sep 17 00:00:00 2001

From: Kari Argillander <kari.argillander@gmail.com>

Date: Wed, 25 Aug 2021 21:24:35 +0300

Subject: [Backport d4e8e135a9af] src: Fix integer overflow in ni_fiemap

 with fiemap_prep()

Use fiemap_prep() to check valid flags. It also shrink request scope

(@len) to what the fs can actually handle.

This address following Smatch static checker warning:

	src/frecord.c:1894 ni_fiemap()

	warn: potential integer overflow from user 'vbo + len'

Because fiemap_prep() shrinks @len this cannot happened anymore.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

Link: lore.kernel.org/ntfs3/20210825080440.GA17407@kili/

Fixes: 4342306f0f0d ("src: Add file operations and implementation")

Signed-off-by: Kari Argillander <kari.argillander@gmail.com>

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

---

 src/file.c | 5 +++--

 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/file.c b/src/file.c

index 89557d60a9b0f0e657ce9465504b417bbb50ed04..f9c9a8c91b46d6fad597c954c3b4a2cd331ebfb6 100644

--- a/src/file.c

+++ b/src/file.c

@@ -1212,8 +1212,9 @@ int ntfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,

 	int err;

 	struct ntfs_inode *ni = ntfs_i(inode);

-	if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR)

-		return -EOPNOTSUPP;

+	err = fiemap_prep(inode, fieinfo, start, &len, ~FIEMAP_FLAG_XATTR);

+	if (err)

+		return err;

 	ni_lock(ni);

-- 

2.31.1