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From: Thomas Huth <thuth@redhat.com>
To: Namjae Jeon <linkinjeon@kernel.org>, Steve French <smfrench@gmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>,
	Tom Talpey <tom@talpey.com>,
	linux-cifs@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH 2/4] smb: server: Make sure that passkey is not leaked on the heap in user_config.c
Date: Mon, 10 Aug 2026 14:58:55 +0200	[thread overview]
Message-ID: <20260810125857.1009618-3-thuth@redhat.com> (raw)
In-Reply-To: <20260810125857.1009618-1-thuth@redhat.com>

From: Thomas Huth <thuth@redhat.com>

Use kfree_sensitive() to free the user->passkey (and the struct
ksmbd_login_response in ksmbd_login_user() that contains the same
information) to avoid that this information could leak somewhere
else via the heap.

Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 fs/smb/server/mgmt/user_config.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/smb/server/mgmt/user_config.c b/fs/smb/server/mgmt/user_config.c
index cf45841d9d1b9..76b74d68369d8 100644
--- a/fs/smb/server/mgmt/user_config.c
+++ b/fs/smb/server/mgmt/user_config.c
@@ -27,7 +27,7 @@ struct ksmbd_user *ksmbd_login_user(const char *account)
 
 	user = ksmbd_alloc_user(resp, resp_ext);
 out:
-	kvfree(resp);
+	kvfree_sensitive(resp, sizeof(*resp));
 	return user;
 }
 
@@ -70,7 +70,7 @@ struct ksmbd_user *ksmbd_alloc_user(struct ksmbd_login_response *resp,
 
 err_free:
 	kfree(user->name);
-	kfree(user->passkey);
+	kfree_sensitive(user->passkey);
 	kfree(user);
 	return NULL;
 }
@@ -80,7 +80,7 @@ void ksmbd_free_user(struct ksmbd_user *user)
 	ksmbd_ipc_logout_request(user->name, user->flags);
 	kfree(user->sgid);
 	kfree(user->name);
-	kfree(user->passkey);
+	kfree_sensitive(user->passkey);
 	kfree(user);
 }
 
-- 
2.55.0


  parent reply	other threads:[~2026-08-10 12:59 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-10 12:58 [PATCH 0/4] smb: server: Clear sensitive data before freeing it Thomas Huth
2026-08-10 12:58 ` [PATCH 1/4] smb: server: Clear sensitive stack and heap data in auth.c Thomas Huth
2026-08-10 12:58 ` Thomas Huth [this message]
2026-08-10 12:58 ` [PATCH 3/4] smb: server: Free session data with kfree_sensitive() to avoid leaking of data Thomas Huth
2026-08-10 12:58 ` [PATCH 4/4] smb: server: Free sensitive connection data with kfree_sensitive() Thomas Huth

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