bcachefs: Fix missing locking for dentry->d_parent access
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
diff --git a/fs/bcachefs/xattr.c b/fs/bcachefs/xattr.c
index a39ff0c..79d9826 100644
--- a/fs/bcachefs/xattr.c
+++ b/fs/bcachefs/xattr.c
@@ -552,6 +552,14 @@
s.v = v + 1;
s.defined = true;
} else {
+ /*
+ * Check if this option was set on the parent - if so, switched
+ * back to inheriting from the parent:
+ *
+ * rename() also has to deal with keeping inherited options up
+ * to date - see bch2_reinherit_attrs()
+ */
+ spin_lock(&dentry->d_lock);
if (!IS_ROOT(dentry)) {
struct bch_inode_info *dir =
to_bch_ei(d_inode(dentry->d_parent));
@@ -560,6 +568,7 @@
} else {
s.v = 0;
}
+ spin_unlock(&dentry->d_lock);
s.defined = false;
}
