afs: Fix updating of i_mode due to 3rd party change

Fix afs_apply_status() to mask off the irrelevant bits from status->mode
when OR'ing them into i_mode.  This can happen when a 3rd party chmod
occurs.

Also fix afs_inode_init_from_status() to mask off the mode bits when
initialising i_mode.

Fixes: 260a980317da ("[AFS]: Add "directory write" support.")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index 1156b2df28d36afe27917af02a95b423aab53e66..9f83e671c7857cff4720b99a8dbd9880636d0b77 100644 (file)
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -103,13 +103,13 @@ static int afs_inode_init_from_status(struct afs_operation *op,
 
        switch (status->type) {
        case AFS_FTYPE_FILE:
-               inode->i_mode   = S_IFREG | status->mode;
+               inode->i_mode   = S_IFREG | (status->mode & S_IALLUGO);
                inode->i_op     = &afs_file_inode_operations;
                inode->i_fop    = &afs_file_operations;
                inode->i_mapping->a_ops = &afs_fs_aops;
                break;
        case AFS_FTYPE_DIR:
-               inode->i_mode   = S_IFDIR | status->mode;
+               inode->i_mode   = S_IFDIR |  (status->mode & S_IALLUGO);
                inode->i_op     = &afs_dir_inode_operations;
                inode->i_fop    = &afs_dir_file_operations;
                inode->i_mapping->a_ops = &afs_dir_aops;
@@ -199,7 +199,7 @@ static void afs_apply_status(struct afs_operation *op,
        if (status->mode != vnode->status.mode) {
                mode = inode->i_mode;
                mode &= ~S_IALLUGO;
-               mode |= status->mode;
+               mode |= status->mode & S_IALLUGO;
                WRITE_ONCE(inode->i_mode, mode);
        }