ksmbd: fix credit count leakage

This patch fix the failure from smb2.credits.single_req_credits_granted
test. When client send 8192 credit request, ksmbd return 8191 credit
granted. ksmbd should give maximum possible credits that must be granted
within the range of not exceeding the max credit to client.

Cc: stable@vger.kernel.org
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c
index 1632b2a1e51682e1d759957e94ed8442e794014f..bec885c007ce2c9b2f3f6b6b9d3c24c006a2b756 100644 (file)
--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -326,13 +326,9 @@ int smb2_set_rsp_credits(struct ksmbd_work *work)
        if (hdr->Command == SMB2_NEGOTIATE)
                aux_max = 1;
        else
-               aux_max = conn->vals->max_credits - credit_charge;
+               aux_max = conn->vals->max_credits - conn->total_credits;
        credits_granted = min_t(unsigned short, credits_requested, aux_max);
 
-       if (conn->vals->max_credits - conn->total_credits < credits_granted)
-               credits_granted = conn->vals->max_credits -
-                       conn->total_credits;
-
        conn->total_credits += credits_granted;
        work->credits_granted += credits_granted;