befs: ensure fast symlinks are NUL-terminated

Ensure fast symlink targets are NUL-terminated, even if corrupted
on-disk.

Cc: Sergey S. Kostyliov <rathamahata@php4.ru>
Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 4 insertions, 1 deletions

diff --git a/fs/befs/linuxvfs.c b/fs/befs/linuxvfs.c
index b6dfee37c7b7..d06cb023ad02 100644
--- a/fs/befs/linuxvfs.c
+++ b/fs/befs/linuxvfs.c
@@ -378,7 +378,8 @@ static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
                 inode->i_size = 0;
                 inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
                 strncpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
-                        BEFS_SYMLINK_LEN);
+                        BEFS_SYMLINK_LEN - 1);
+                befs_ino->i_data.symlink[BEFS_SYMLINK_LEN - 1] = '\0';
         } else {
                 int num_blks;
 
@@ -477,6 +478,8 @@ befs_follow_link(struct dentry *dentry, struct nameidata *nd)
                         kfree(link);
                         befs_error(sb, "Failed to read entire long symlink");
                         link = ERR_PTR(-EIO);
+                } else {
+                        link[len - 1] = '\0';
                 }
         } else {
                 link = befs_ino->i_data.symlink;