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* [PATCH] ksmbd: fix leak of transform buffer on encrypt_resp() failure
@ 2025-11-04 10:02 Qianchang Zhao
  0 siblings, 0 replies; 7+ messages in thread
From: Qianchang Zhao @ 2025-11-04 10:02 UTC (permalink / raw)
  To: harm0niakwer; +Cc: Qianchang Zhao, Zhitong Liu, stable

When encrypt_resp() fails at the send path, we only set
STATUS_DATA_ERROR but leave the transform buffer allocated (work->tr_buf
in this tree). Repeating this path leaks kernel memory and can lead to
OOM (DoS) when encryption is required.

Reproduced on: Linux v6.18-rc2 (self-built test kernel)

Fix by freeing the transform buffer and forcing plaintext error reply.

Reported-by: Qianchang Zhao <pioooooooooip@gmail.com>
Reported-by: Zhitong Liu <liuzhitong1993@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Qianchang Zhao <pioooooooooip@gmail.com>
---
 fs/smb/server/server.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/smb/server/server.c b/fs/smb/server/server.c
index 7b01c7589..15dd13e76 100644
--- a/fs/smb/server/server.c
+++ b/fs/smb/server/server.c
@@ -246,11 +246,11 @@ static void __handle_ksmbd_work(struct ksmbd_work *work,
 		rc = conn->ops->encrypt_resp(work);
 		if (rc < 0) {
 			conn->ops->set_rsp_status(work, STATUS_DATA_ERROR);
-			 work->encrypted = false;
-    			 	if (work->tr_buf) {
-            				kvfree(work->tr_buf);
-            				work->tr_buf = NULL;
-       			   	}
+			work->encrypted = false;
+			if (work->tr_buf) {
+				kvfree(work->tr_buf);
+				work->tr_buf = NULL;
+			}
 		}
 	}
 	if (work->sess)
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 7+ messages in thread
[parent not found: <2025110432-maimed-polio-c7b4@gregkh>]
* [PATCH] ksmbd: fix leak of transform buffer on encrypt_resp() failure
@ 2025-11-04 14:09 Qianchang Zhao
  0 siblings, 0 replies; 7+ messages in thread
From: Qianchang Zhao @ 2025-11-04 14:09 UTC (permalink / raw)
  To: harm0niakwer; +Cc: Qianchang Zhao, Zhitong Liu, stable

When encrypt_resp() fails at the send path, we only set
STATUS_DATA_ERROR but leave the transform buffer allocated (work->tr_buf
in this tree). Repeating this path leaks kernel memory and can lead to
OOM (DoS) when encryption is required.

Reproduced on: Linux v6.18-rc2 (self-built test kernel)

Fix by freeing the transform buffer and forcing plaintext error reply.

Reported-by: Qianchang Zhao <pioooooooooip@gmail.com>
Reported-by: Zhitong Liu <liuzhitong1993@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Qianchang Zhao <pioooooooooip@gmail.com>
---
 fs/smb/server/server.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/fs/smb/server/server.c b/fs/smb/server/server.c
index 40420544c..15dd13e76 100644
--- a/fs/smb/server/server.c
+++ b/fs/smb/server/server.c
@@ -244,8 +244,14 @@ static void __handle_ksmbd_work(struct ksmbd_work *work,
 	if (work->sess && work->sess->enc && work->encrypted &&
 	    conn->ops->encrypt_resp) {
 		rc = conn->ops->encrypt_resp(work);
-		if (rc < 0)
+		if (rc < 0) {
 			conn->ops->set_rsp_status(work, STATUS_DATA_ERROR);
+			work->encrypted = false;
+			if (work->tr_buf) {
+				kvfree(work->tr_buf);
+				work->tr_buf = NULL;
+			}
+		}
 	}
 	if (work->sess)
 		ksmbd_user_session_put(work->sess);
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 7+ messages in thread
* [PATCH] ksmbd: fix leak of transform buffer on encrypt_resp() failure
@ 2025-11-04 14:11 Qianchang Zhao
  0 siblings, 0 replies; 7+ messages in thread
From: Qianchang Zhao @ 2025-11-04 14:11 UTC (permalink / raw)
  To: harm0niakwer; +Cc: Qianchang Zhao, Zhitong Liu, stable

When encrypt_resp() fails at the send path, we only set
STATUS_DATA_ERROR but leave the transform buffer allocated (work->tr_buf
in this tree). Repeating this path leaks kernel memory and can lead to
OOM (DoS) when encryption is required.

Reproduced on: Linux v6.18-rc2 (self-built test kernel)

Fix by freeing the transform buffer and forcing plaintext error reply.

Reported-by: Qianchang Zhao <pioooooooooip@gmail.com>
Reported-by: Zhitong Liu <liuzhitong1993@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Qianchang Zhao <pioooooooooip@gmail.com>
---
 fs/smb/server/server.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/fs/smb/server/server.c b/fs/smb/server/server.c
index 40420544c..15dd13e76 100644
--- a/fs/smb/server/server.c
+++ b/fs/smb/server/server.c
@@ -244,8 +244,14 @@ static void __handle_ksmbd_work(struct ksmbd_work *work,
 	if (work->sess && work->sess->enc && work->encrypted &&
 	    conn->ops->encrypt_resp) {
 		rc = conn->ops->encrypt_resp(work);
-		if (rc < 0)
+		if (rc < 0) {
 			conn->ops->set_rsp_status(work, STATUS_DATA_ERROR);
+			work->encrypted = false;
+			if (work->tr_buf) {
+				kvfree(work->tr_buf);
+				work->tr_buf = NULL;
+			}
+		}
 	}
 	if (work->sess)
 		ksmbd_user_session_put(work->sess);
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2025-11-05  5:15 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-11-04 10:02 [PATCH] ksmbd: fix leak of transform buffer on encrypt_resp() failure Qianchang Zhao
     [not found] <2025110432-maimed-polio-c7b4@gregkh>
2025-11-04 10:03 ` Qianchang Zhao
2025-11-04 11:51   ` Namjae Jeon
2025-11-04 14:12 ` Qianchang Zhao
2025-11-05  5:14   ` Namjae Jeon
  -- strict thread matches above, loose matches on Subject: below --
2025-11-04 14:09 Qianchang Zhao
2025-11-04 14:11 Qianchang Zhao

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