FAILED: patch "[PATCH] ksmbd: Fix the missing xa_store error check" failed to apply to 5.15-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 3abab905b14f4ba756d413f37f1fb02b708eee93
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2024110956-unwired-hence-eb8d@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 3abab905b14f4ba756d413f37f1fb02b708eee93 Mon Sep 17 00:00:00 2001
From: Jinjie Ruan <ruanjinjie@huawei.com>
Date: Mon, 28 Oct 2024 08:28:30 +0900
Subject: [PATCH] ksmbd: Fix the missing xa_store error check

xa_store() can fail, it return xa_err(-EINVAL) if the entry cannot
be stored in an XArray, or xa_err(-ENOMEM) if memory allocation failed,
so check error for xa_store() to fix it.

Cc: stable@vger.kernel.org
Fixes: b685757c7b08 ("ksmbd: Implements sess->rpc_handle_list as xarray")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/smb/server/mgmt/user_session.c b/fs/smb/server/mgmt/user_session.c
index 1e4624e9d434..9756a4bbfe54 100644
--- a/fs/smb/server/mgmt/user_session.c
+++ b/fs/smb/server/mgmt/user_session.c
@@ -90,7 +90,7 @@ static int __rpc_method(char *rpc_name)
 
 int ksmbd_session_rpc_open(struct ksmbd_session *sess, char *rpc_name)
 {
-	struct ksmbd_session_rpc *entry;
+	struct ksmbd_session_rpc *entry, *old;
 	struct ksmbd_rpc_command *resp;
 	int method;
 
@@ -106,16 +106,19 @@ int ksmbd_session_rpc_open(struct ksmbd_session *sess, char *rpc_name)
 	entry->id = ksmbd_ipc_id_alloc();
 	if (entry->id < 0)
 		goto free_entry;
-	xa_store(&sess->rpc_handle_list, entry->id, entry, GFP_KERNEL);
+	old = xa_store(&sess->rpc_handle_list, entry->id, entry, GFP_KERNEL);
+	if (xa_is_err(old))
+		goto free_id;
 
 	resp = ksmbd_rpc_open(sess, entry->id);
 	if (!resp)
-		goto free_id;
+		goto erase_xa;
 
 	kvfree(resp);
 	return entry->id;
-free_id:
+erase_xa:
 	xa_erase(&sess->rpc_handle_list, entry->id);
+free_id:
 	ksmbd_rpc_id_free(entry->id);
 free_entry:
 	kfree(entry);