[PATCH -next] ksmbd: fix memory leak in smb2_lock()

[PATCH -next] ksmbd: fix memory leak in smb2_lock()

[Zizhi Wo]

In smb2_lock(), if setup_async_work() executes successfully,
work->cancel_argv will bind the argv that generated by kmalloc(). And
release_async_work() is called in ksmbd_conn_try_dequeue_request() or
smb2_lock() to release argv.
However, when setup_async_work function fails, work->cancel_argv has not
been bound to the argv, resulting in the previously allocated argv not
being released. Call kfree() to fix it.

when setup_async_work fails, the code will go to the
"out" branch, resulting in the previously allocated "argv" not being
released. Call kfree() to fix it.

Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
---
 fs/smb/server/smb2pdu.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c
index 658209839729..67cbeb713f70 100644
--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -7078,6 +7078,7 @@ int smb2_lock(struct ksmbd_work *work)
 						      smb2_remove_blocked_lock,
 						      argv);
 				if (rc) {
+					kfree(argv);
 					err = -ENOMEM;
 					goto out;
 				}
-- 
2.39.2

Re: [PATCH -next] ksmbd: fix memory leak in smb2_lock()

[Namjae Jeon]

2023-12-01 23:50 GMT+09:00, Zizhi Wo <wozizhi@huawei.com>:
> In smb2_lock(), if setup_async_work() executes successfully,
> work->cancel_argv will bind the argv that generated by kmalloc(). And
> release_async_work() is called in ksmbd_conn_try_dequeue_request() or
> smb2_lock() to release argv.
> However, when setup_async_work function fails, work->cancel_argv has not
> been bound to the argv, resulting in the previously allocated argv not
> being released. Call kfree() to fix it.
>
> when setup_async_work fails, the code will go to the
> "out" branch, resulting in the previously allocated "argv" not being
> released. Call kfree() to fix it.
>
> Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
> Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>

Applied it to #ksmbd-for-next-next .
Thanks.

Re: [PATCH -next] ksmbd: fix memory leak in smb2_lock()

[Zizhi Wo]

在 2023/12/2 11:54, Namjae Jeon 写道:
> 2023-12-01 23:50 GMT+09:00, Zizhi Wo <wozizhi@huawei.com>:
>> In smb2_lock(), if setup_async_work() executes successfully,
>> work->cancel_argv will bind the argv that generated by kmalloc(). And
>> release_async_work() is called in ksmbd_conn_try_dequeue_request() or
>> smb2_lock() to release argv.
>> However, when setup_async_work function fails, work->cancel_argv has not
>> been bound to the argv, resulting in the previously allocated argv not
>> being released. Call kfree() to fix it.
>>
>> when setup_async_work fails, the code will go to the
>> "out" branch, resulting in the previously allocated "argv" not being
>> released. Call kfree() to fix it.
>>
>> Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
>> Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
> Acked-by: Namjae Jeon <linkinjeon@kernel.org>
> 
> Applied it to #ksmbd-for-next-next .
> Thanks.

Thanks, but I found a redundant paragraph in my commit message, and I 
will send version V2 to fix it.