scsi: target: Fix incorrect use of cpumask_t

In commit d72d827f2f26, I used 'cpumask_t' incorrectly:

    void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
    {
            int ord, cpu;
            cpumask_t conn_allowed_cpumask;
            ......
    }

    static ssize_t lio_target_wwn_cpus_allowed_list_store(
                   struct config_item *item, const char *page, size_t count)
    {
            int ret;
            char *orig;
            cpumask_t new_allowed_cpumask;
            ......
    }

The correct pattern should be as follows:

    cpumask_var_t mask;

    if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
            return -ENOMEM;
    ... use 'mask' here ...
    free_cpumask_var(mask);

Link: https://lore.kernel.org/r/20220516054721.1548-1-mingzhe.zou@easystack.cn
Fixes: d72d827f2f26 ("scsi: target: Add iscsi/cpus_allowed_list in configfs")
Reported-by: Test Bot <zgrieee@gmail.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Mingzhe Zou <mingzhe.zou@easystack.cn>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c
index 6fe6a6b..ddf6c2a 100644 (file)
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -3596,10 +3596,7 @@ static int iscsit_send_reject(
 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
 {
        int ord, cpu;
-       cpumask_t conn_allowed_cpumask;
-
-       cpumask_and(&conn_allowed_cpumask, iscsit_global->allowed_cpumask,
-                   cpu_online_mask);
+       cpumask_var_t conn_allowed_cpumask;
 
        /*
         * bitmap_id is assigned from iscsit_global->ts_bitmap from
@@ -3609,13 +3606,28 @@ void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
         * iSCSI connection's RX/TX threads will be scheduled to
         * execute upon.
         */
-       cpumask_clear(conn->conn_cpumask);
-       ord = conn->bitmap_id % cpumask_weight(&conn_allowed_cpumask);
-       for_each_cpu(cpu, &conn_allowed_cpumask) {
-               if (ord-- == 0) {
-                       cpumask_set_cpu(cpu, conn->conn_cpumask);
-                       return;
+       if (!zalloc_cpumask_var(&conn_allowed_cpumask, GFP_KERNEL)) {
+               ord = conn->bitmap_id % cpumask_weight(cpu_online_mask);
+               for_each_online_cpu(cpu) {
+                       if (ord-- == 0) {
+                               cpumask_set_cpu(cpu, conn->conn_cpumask);
+                               return;
+                       }
+               }
+       } else {
+               cpumask_and(conn_allowed_cpumask, iscsit_global->allowed_cpumask,
+                       cpu_online_mask);
+
+               cpumask_clear(conn->conn_cpumask);
+               ord = conn->bitmap_id % cpumask_weight(conn_allowed_cpumask);
+               for_each_cpu(cpu, conn_allowed_cpumask) {
+                       if (ord-- == 0) {
+                               cpumask_set_cpu(cpu, conn->conn_cpumask);
+                               free_cpumask_var(conn_allowed_cpumask);
+                               return;
+                       }
                }
+               free_cpumask_var(conn_allowed_cpumask);
        }
        /*
         * This should never be reached..

diff --git a/drivers/target/iscsi/iscsi_target_configfs.c b/drivers/target/iscsi/iscsi_target_configfs.c
index 0cedcfe..57b4fd5 100644 (file)
--- a/drivers/target/iscsi/iscsi_target_configfs.c
+++ b/drivers/target/iscsi/iscsi_target_configfs.c
@@ -1137,23 +1137,27 @@ static ssize_t lio_target_wwn_cpus_allowed_list_show(
 static ssize_t lio_target_wwn_cpus_allowed_list_store(
                struct config_item *item, const char *page, size_t count)
 {
-       int ret;
+       int ret = -ENOMEM;
        char *orig;
-       cpumask_t new_allowed_cpumask;
+       cpumask_var_t new_allowed_cpumask;
+
+       if (!zalloc_cpumask_var(&new_allowed_cpumask, GFP_KERNEL))
+               goto out;
 
        orig = kstrdup(page, GFP_KERNEL);
        if (!orig)
-               return -ENOMEM;
+               goto out_free_cpumask;
 
-       cpumask_clear(&new_allowed_cpumask);
-       ret = cpulist_parse(orig, &new_allowed_cpumask);
+       ret = cpulist_parse(orig, new_allowed_cpumask);
+       if (!ret)
+               cpumask_copy(iscsit_global->allowed_cpumask,
+                            new_allowed_cpumask);
 
        kfree(orig);
-       if (ret != 0)
-               return ret;
-
-       cpumask_copy(iscsit_global->allowed_cpumask, &new_allowed_cpumask);
-       return count;
+out_free_cpumask:
+       free_cpumask_var(new_allowed_cpumask);
+out:
+       return ret ? ret : count;
 }
 
 CONFIGFS_ATTR(lio_target_wwn_, cpus_allowed_list);