From:   Hangyu Hua <hbh25y@gmail.com>
To:     linkinjeon@kernel.org, sfrench@samba.org, senozhatsky@chromium.org,
        tom@talpey.com, lsahlber@redhat.com, hyc.lee@gmail.com
Cc:     linux-cifs@vger.kernel.org, linux-kernel@vger.kernel.org,
        Hangyu Hua <hbh25y@gmail.com>
Subject: [PATCH v2] ksmbd: fix possible memory leak in smb2_lock()
Date:   Mon,  6 Feb 2023 10:36:30 +0800
Message-Id: <20230206023630.9457-1-hbh25y@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

argv needs to be free when setup_async_work fails or when the current
process is woken up.

Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
---

v2: avoid NULL pointer dereference in set_close_state_blocked_works()

 fs/ksmbd/smb2pdu.c   | 5 +++++
 fs/ksmbd/vfs_cache.c | 2 ++
 2 files changed, 7 insertions(+)

diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index d681f91947d9..177a24704021 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -7050,6 +7050,7 @@ int smb2_lock(struct ksmbd_work *work)
 						      smb2_remove_blocked_lock,
 						      argv);
 				if (rc) {
+					kfree(argv);
 					err = -ENOMEM;
 					goto out;
 				}
@@ -7072,6 +7073,8 @@ int smb2_lock(struct ksmbd_work *work)
 						spin_lock(&fp->f_lock);
 						list_del(&work->fp_entry);
 						spin_unlock(&fp->f_lock);
+						kfree(argv);
+						work->cancel_fn = NULL;
 						rsp->hdr.Status =
 							STATUS_CANCELLED;
 						kfree(smb_lock);
@@ -7096,6 +7099,8 @@ int smb2_lock(struct ksmbd_work *work)
 				spin_lock(&fp->f_lock);
 				list_del(&work->fp_entry);
 				spin_unlock(&fp->f_lock);
+				kfree(argv);
+				work->cancel_fn = NULL;
 				goto retry;
 			} else if (!rc) {
 				spin_lock(&work->conn->llist_lock);
diff --git a/fs/ksmbd/vfs_cache.c b/fs/ksmbd/vfs_cache.c
index da9163b00350..eb95c16393b7 100644
--- a/fs/ksmbd/vfs_cache.c
+++ b/fs/ksmbd/vfs_cache.c
@@ -372,6 +372,8 @@ static void set_close_state_blocked_works(struct ksmbd_file *fp)
 		list_del(&cancel_work->fp_entry);
 		cancel_work->state = KSMBD_WORK_CLOSED;
 		cancel_work->cancel_fn(cancel_work->cancel_argv);
+		kfree(cancel_work->cancel_argv);
+		cancel_work->cancel_fn = NULL;
 	}
 	spin_unlock(&fp->f_lock);
 }
-- 
2.34.1