All of lore.kernel.org
 help / color / mirror / Atom feed
From: Jia-Ju Bai <baijiaju1990@gmail.com>
To: sathya.prakash@broadcom.com, chaitra.basappa@broadcom.com,
	suganath-prabu.subramani@broadcom.com, jejb@linux.ibm.com,
	martin.petersen@oracle.com
Cc: MPT-FusionLinux.pdl@broadcom.com, linux-scsi@vger.kernel.org,
	linux-kernel@vger.kernel.org, Jia-Ju Bai <baijiaju1990@gmail.com>
Subject: [PATCH] scsi: mpt3sas: Fix a possible null-pointer dereference in mpt3sas_transport_update_links()
Date: Mon, 29 Jul 2019 11:08:51 +0800	[thread overview]
Message-ID: <20190729030851.22059-1-baijiaju1990@gmail.com> (raw)

In mpt3sas_transport_update_links(), there is an if statement 
on line 994 to check whether mpt3sas_phy->phy is NULL:
    if (mpt3sas_phy->phy)

When mpt3sas_phy->phy is NULL, it is used on line 999:
    dev_printk(KERN_INFO, &mpt3sas_phy->phy->dev, ...)

Thus, a possible null-pointer dereference may occur.

To fix this bug, mpt3sas_phy->phy is checked before being used.

This bug is found by a static analysis tool STCheck written by us.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
---
 drivers/scsi/mpt3sas/mpt3sas_transport.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/mpt3sas/mpt3sas_transport.c b/drivers/scsi/mpt3sas/mpt3sas_transport.c
index 5324662751bf..df790a9877a0 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_transport.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_transport.c
@@ -995,7 +995,8 @@ mpt3sas_transport_update_links(struct MPT3SAS_ADAPTER *ioc,
 		mpt3sas_phy->phy->negotiated_linkrate =
 		    _transport_convert_phy_link_rate(link_rate);
 
-	if ((ioc->logging_level & MPT_DEBUG_TRANSPORT))
+	if ((ioc->logging_level & MPT_DEBUG_TRANSPORT) && 
+			mpt3sas_phy->phy)
 		dev_printk(KERN_INFO, &mpt3sas_phy->phy->dev,
 		    "refresh: parent sas_addr(0x%016llx),\n"
 		    "\tlink_rate(0x%02x), phy(%d)\n"
-- 
2.17.0


                 reply	other threads:[~2019-07-29  3:09 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190729030851.22059-1-baijiaju1990@gmail.com \
    --to=baijiaju1990@gmail.com \
    --cc=MPT-FusionLinux.pdl@broadcom.com \
    --cc=chaitra.basappa@broadcom.com \
    --cc=jejb@linux.ibm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    --cc=martin.petersen@oracle.com \
    --cc=sathya.prakash@broadcom.com \
    --cc=suganath-prabu.subramani@broadcom.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.