fs/ntfs3: Harden against integer overflows

[ Upstream commit e001e60869390686809663c02bceb1d3922548fb ]

Smatch complains that the "add_bytes" is not to be trusted.  Use
size_add() to prevent an integer overflow.

Fixes: be71b5cba2e6 ("fs/ntfs3: Add attrib operations")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/ntfs3/xattr.c b/fs/ntfs3/xattr.c
index 7de8718..ea582b4 100644 (file)
--- a/fs/ntfs3/xattr.c
+++ b/fs/ntfs3/xattr.c
@@ -107,7 +107,7 @@ static int ntfs_read_ea(struct ntfs_inode *ni, struct EA_FULL **ea,
                return -EFBIG;
 
        /* Allocate memory for packed Ea. */
-       ea_p = kmalloc(size + add_bytes, GFP_NOFS);
+       ea_p = kmalloc(size_add(size, add_bytes), GFP_NOFS);
        if (!ea_p)
                return -ENOMEM;