s390/qeth: streamline SNMP cmd code

Apply some cleanups to qeth_snmp_command() and its callback:
1. when accessing the user data, use the proper struct instead of
   hard-coded offsets. Also copy the request data straight into the
   allocated cmd, skipping the extra memdup_user() to a tmp buffer.
2. capping the request length is no longer needed, the same check gets
   applied at a base level in qeth_alloc_cmd().
3. clean up some duplicated (and misindented) trace statements.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 3875f70118e4d888b5ecc5a2bb890362710188c1..efb9a27b916ea0ecd3a4310ca119a1ab36c8a364 100644 (file)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -4320,18 +4320,13 @@ static int qeth_snmp_command_cb(struct qeth_card *card,
                return -ENOSPC;
        }
        QETH_CARD_TEXT_(card, 4, "snore%i",
-                      cmd->data.setadapterparms.hdr.used_total);
+                       cmd->data.setadapterparms.hdr.used_total);
        QETH_CARD_TEXT_(card, 4, "sseqn%i",
-               cmd->data.setadapterparms.hdr.seq_no);
+                       cmd->data.setadapterparms.hdr.seq_no);
        /*copy entries to user buffer*/
        memcpy(qinfo->udata + qinfo->udata_offset, snmp_data, data_len);
        qinfo->udata_offset += data_len;
 
-       /* check if all replies received ... */
-               QETH_CARD_TEXT_(card, 4, "srtot%i",
-                              cmd->data.setadapterparms.hdr.used_total);
-               QETH_CARD_TEXT_(card, 4, "srseq%i",
-                              cmd->data.setadapterparms.hdr.seq_no);
        if (cmd->data.setadapterparms.hdr.seq_no <
            cmd->data.setadapterparms.hdr.used_total)
                return 1;
@@ -4340,9 +4335,8 @@ static int qeth_snmp_command_cb(struct qeth_card *card,
 
 static int qeth_snmp_command(struct qeth_card *card, char __user *udata)
 {
+       struct qeth_snmp_ureq __user *ureq;
        struct qeth_cmd_buffer *iob;
-       struct qeth_ipa_cmd *cmd;
-       struct qeth_snmp_ureq *ureq;
        unsigned int req_len;
        struct qeth_arp_query_info qinfo = {0, };
        int rc = 0;
@@ -4356,34 +4350,28 @@ static int qeth_snmp_command(struct qeth_card *card, char __user *udata)
            IS_LAYER3(card))
                return -EOPNOTSUPP;
 
-       /* skip 4 bytes (data_len struct member) to get req_len */
-       if (copy_from_user(&req_len, udata + sizeof(int), sizeof(int)))
+       ureq = (struct qeth_snmp_ureq __user *) udata;
+       if (get_user(qinfo.udata_len, &ureq->hdr.data_len) ||
+           get_user(req_len, &ureq->hdr.req_len))
+               return -EFAULT;
+
+       iob = qeth_get_adapter_cmd(card, IPA_SETADP_SET_SNMP_CONTROL, req_len);
+       if (!iob)
+               return -ENOMEM;
+
+       if (copy_from_user(&__ipa_cmd(iob)->data.setadapterparms.data.snmp,
+                          &ureq->cmd, req_len)) {
+               qeth_put_cmd(iob);
                return -EFAULT;
-       if (req_len + offsetof(struct qeth_ipacmd_setadpparms, data) +
-           offsetof(struct qeth_ipa_cmd, data) + IPA_PDU_HEADER_SIZE >
-           QETH_BUFSIZE)
-               return -EINVAL;
-       ureq = memdup_user(udata, req_len + sizeof(struct qeth_snmp_ureq_hdr));
-       if (IS_ERR(ureq)) {
-               QETH_CARD_TEXT(card, 2, "snmpnome");
-               return PTR_ERR(ureq);
        }
-       qinfo.udata_len = ureq->hdr.data_len;
+
        qinfo.udata = kzalloc(qinfo.udata_len, GFP_KERNEL);
        if (!qinfo.udata) {
-               kfree(ureq);
+               qeth_put_cmd(iob);
                return -ENOMEM;
        }
        qinfo.udata_offset = sizeof(struct qeth_snmp_ureq_hdr);
 
-       iob = qeth_get_adapter_cmd(card, IPA_SETADP_SET_SNMP_CONTROL, req_len);
-       if (!iob) {
-               rc = -ENOMEM;
-               goto out;
-       }
-
-       cmd = __ipa_cmd(iob);
-       memcpy(&cmd->data.setadapterparms.data.snmp, &ureq->cmd, req_len);
        rc = qeth_send_ipa_cmd(card, iob, qeth_snmp_command_cb, &qinfo);
        if (rc)
                QETH_DBF_MESSAGE(2, "SNMP command failed on device %x: (%#x)\n",
@@ -4392,8 +4380,7 @@ static int qeth_snmp_command(struct qeth_card *card, char __user *udata)
                if (copy_to_user(udata, qinfo.udata, qinfo.udata_len))
                        rc = -EFAULT;
        }
-out:
-       kfree(ureq);
+
        kfree(qinfo.udata);
        return rc;
 }