Adding upstream version 4.19.304.upstream/4.19.304upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 21 insertions, 1 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 9e8fca598..60b57e0bc 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2575,6 +2575,26 @@ struct dentry *lookup_one_len_unlocked(const char *name,
 }
 EXPORT_SYMBOL(lookup_one_len_unlocked);
 
+/*
+ * Like lookup_one_len_unlocked(), except that it yields ERR_PTR(-ENOENT)
+ * on negatives.  Returns known positive or ERR_PTR(); that's what
+ * most of the users want.  Note that pinned negative with unlocked parent
+ * _can_ become positive at any time, so callers of lookup_one_len_unlocked()
+ * need to be very careful; pinned positives have ->d_inode stable, so
+ * this one avoids such problems.
+ */
+struct dentry *lookup_positive_unlocked(const char *name,
+				       struct dentry *base, int len)
+{
+	struct dentry *ret = lookup_one_len_unlocked(name, base, len);
+	if (!IS_ERR(ret) && d_is_negative(ret)) {
+		dput(ret);
+		ret = ERR_PTR(-ENOENT);
+	}
+	return ret;
+}
+EXPORT_SYMBOL(lookup_positive_unlocked);
+
 #ifdef CONFIG_UNIX98_PTYS
 int path_pts(struct path *path)
 {
@@ -2593,7 +2613,7 @@ int path_pts(struct path *path)
 	this.name = "pts";
 	this.len = 3;
 	child = d_hash_and_lookup(parent, &this);
-	if (!child)
+	if (IS_ERR_OR_NULL(child))
 		return -ENOENT;
 
 	path->dentry = child;