target: Fix ERR_PTR dereferencing bugs

transport_init_session() and core_tmr_alloc_req() never return NULL,
they only return ERR_PTRs on error.

v2: Fix patch to return PTR_ERR(tl_nexus->se_sess) from Ankit Jain's
feedback.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Ankit Jain <jankit@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 6 insertions, 3 deletions

diff --git a/drivers/target/loopback/tcm_loop.c b/drivers/target/loopback/tcm_loop.c
index dee2a2c909f5..d4fee2a9d66a 100644
--- a/drivers/target/loopback/tcm_loop.c
+++ b/drivers/target/loopback/tcm_loop.c
@@ -386,7 +386,7 @@ static int tcm_loop_device_reset(struct scsi_cmnd *sc)
          */
         se_cmd->se_tmr_req = core_tmr_alloc_req(se_cmd, (void *)tl_tmr,
                                 TMR_LUN_RESET);
-        if (!se_cmd->se_tmr_req)
+        if (IS_ERR(se_cmd->se_tmr_req))
                 goto release;
         /*
          * Locate the underlying TCM struct se_lun from sc->device->lun
@@ -1017,6 +1017,7 @@ static int tcm_loop_make_nexus(
         struct se_portal_group *se_tpg;
         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
         struct tcm_loop_nexus *tl_nexus;
+        int ret = -ENOMEM;
 
         if (tl_tpg->tl_hba->tl_nexus) {
                 printk(KERN_INFO "tl_tpg->tl_hba->tl_nexus already exists\n");
@@ -1033,8 +1034,10 @@ static int tcm_loop_make_nexus(
          * Initialize the struct se_session pointer
          */
         tl_nexus->se_sess = transport_init_session();
-        if (!tl_nexus->se_sess)
+        if (IS_ERR(tl_nexus->se_sess)) {
+                ret = PTR_ERR(tl_nexus->se_sess);
                 goto out;
+        }
         /*
          * Since we are running in 'demo mode' this call with generate a
          * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
@@ -1060,7 +1063,7 @@ static int tcm_loop_make_nexus(
 
 out:
         kfree(tl_nexus);
-        return -ENOMEM;
+        return ret;
 }
 
 static int tcm_loop_drop_nexus(