scsi: bnx2fc: Fix error handling in probe() [Linux 5.0]

This Linux kernel change "scsi: bnx2fc: Fix error handling in probe()" is included in the Linux 5.0 release. This change is authored by Dan Carpenter <dan.carpenter [at] oracle.com> on Thu Jan 24 13:29:40 2019 +0300. The commit for this change in Linux stable tree is b2d3492 (patch).

scsi: bnx2fc: Fix error handling in probe()

There are two issues here.  First if cmgr->hba is not set early enough then
it leads to a NULL dereference.  Second if we don't completely initialize
cmgr->io_bdt_pool[] then we end up dereferencing uninitialized pointers.

Fixes: 853e2bd2103a ("[SCSI] bnx2fc: Broadcom FCoE offload driver")
Signed-off-by: Dan Carpenter <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

There are 4 lines of Linux source code added/deleted in this change. Code changes to Linux kernel are as follows.

 drivers/scsi/bnx2fc/bnx2fc_io.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/bnx2fc/bnx2fc_io.c b/drivers/scsi/bnx2fc/bnx2fc_io.c
index 350257c..bc9f2a2 100644
--- a/drivers/scsi/bnx2fc/bnx2fc_io.c
+++ b/drivers/scsi/bnx2fc/bnx2fc_io.c
@@ -240,6 +240,7 @@ struct bnx2fc_cmd_mgr *bnx2fc_cmd_mgr_alloc(struct bnx2fc_hba *hba)
        return NULL;
    }

+   cmgr->hba = hba;
    cmgr->free_list = kcalloc(arr_sz, sizeof(*cmgr->free_list),
                  GFP_KERNEL);
    if (!cmgr->free_list) {
@@ -256,7 +257,6 @@ struct bnx2fc_cmd_mgr *bnx2fc_cmd_mgr_alloc(struct bnx2fc_hba *hba)
        goto mem_err;
    }

-   cmgr->hba = hba;
    cmgr->cmds = (struct bnx2fc_cmd **)(cmgr + 1);

    for (i = 0; i < arr_sz; i++)  {
@@ -295,7 +295,7 @@ struct bnx2fc_cmd_mgr *bnx2fc_cmd_mgr_alloc(struct bnx2fc_hba *hba)

    /* Allocate pool of io_bdts - one for each bnx2fc_cmd */
    mem_size = num_ios * sizeof(struct io_bdt *);
-   cmgr->io_bdt_pool = kmalloc(mem_size, GFP_KERNEL);
+   cmgr->io_bdt_pool = kzalloc(mem_size, GFP_KERNEL);
    if (!cmgr->io_bdt_pool) {
        printk(KERN_ERR PFX "failed to alloc io_bdt_pool\n");
        goto mem_err;

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