From: Ruben Devos <devosruben6@gmail.com>
Date: Sun, 1 Jun 2025 17:18:55 +0000 (+0200)
Subject: smb: client: add NULL check in automount_fullpath
X-Git-Tag: v6.16-rc1~55^2~11
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=f1e7a277a1736e12cc4bd6d93b8a5c439b8ca20c;p=thirdparty%2Flinux.git

smb: client: add NULL check in automount_fullpath

page is checked for null in __build_path_from_dentry_optional_prefix
when tcon->origin_fullpath is not set. However, the check is missing when
it is set.
Add a check to prevent a potential NULL pointer dereference.

Signed-off-by: Ruben Devos <devosruben6@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
---

diff --git a/fs/smb/client/namespace.c b/fs/smb/client/namespace.c
index e3f9213131c46..a6655807c0865 100644
--- a/fs/smb/client/namespace.c
+++ b/fs/smb/client/namespace.c
@@ -146,6 +146,9 @@ static char *automount_fullpath(struct dentry *dentry, void *page)
 	}
 	spin_unlock(&tcon->tc_lock);
 
+	if (unlikely(!page))
+		return ERR_PTR(-ENOMEM);
+
 	s = dentry_path_raw(dentry, page, PATH_MAX);
 	if (IS_ERR(s))
 		return s;