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Date: Sun, 31 Dec 2023 16:00:22 +0100
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Subject: [PATCH 2/2] net/smc: Improve exception handling in
 smc_llc_cli_add_link_invite()
Content-Language: en-GB
From: Markus Elfring <Markus.Elfring@web.de>
To: linux-s390@vger.kernel.org, netdev@vger.kernel.org,
 kernel-janitors@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
 "D. Wythe" <alibuda@linux.alibaba.com>, Eric Dumazet <edumazet@google.com>,
 Jakub Kicinski <kuba@kernel.org>, Jan Karcher <jaka@linux.ibm.com>,
 Paolo Abeni <pabeni@redhat.com>, Tony Lu <tonylu@linux.alibaba.com>,
 Wen Gu <guwen@linux.alibaba.com>, Wenjia Zhang <wenjia@linux.ibm.com>
References: <8ba404fd-7f41-44a9-9869-84f3af18fb46@web.de>
Cc: LKML <linux-kernel@vger.kernel.org>
In-Reply-To: <8ba404fd-7f41-44a9-9869-84f3af18fb46@web.de>
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From: Markus Elfring <elfring@users.sourceforge.net>
Date: Sun, 31 Dec 2023 15:42:07 +0100

The kfree() function was called in some cases by
the smc_llc_cli_add_link_invite() function during error handling
even if the passed variable contained a null pointer.
This issue was detected by using the Coccinelle software.

* Thus use another label.

* Merge two if statements.

* Omit an initialisation (for the variable =E2=80=9Cini=E2=80=9D)
  which became unnecessary with this refactoring.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
=2D--
 net/smc/smc_llc.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/net/smc/smc_llc.c b/net/smc/smc_llc.c
index 018ce8133b02..2ff24a7feb26 100644
=2D-- a/net/smc/smc_llc.c
+++ b/net/smc/smc_llc.c
@@ -1163,23 +1163,21 @@ static void smc_llc_cli_add_link_invite(struct smc=
_link *link,
 					struct smc_llc_qentry *qentry)
 {
 	struct smc_link_group *lgr =3D smc_get_lgr(link);
-	struct smc_init_info *ini =3D NULL;
+	struct smc_init_info *ini;

 	if (lgr->smc_version =3D=3D SMC_V2) {
 		smc_llc_send_request_add_link(link);
-		goto out;
+		goto free_qentry;
 	}

 	if (lgr->type =3D=3D SMC_LGR_SYMMETRIC ||
-	    lgr->type =3D=3D SMC_LGR_ASYMMETRIC_PEER)
-		goto out;
-
-	if (lgr->type =3D=3D SMC_LGR_SINGLE && lgr->max_links <=3D 1)
-		goto out;
+	    lgr->type =3D=3D SMC_LGR_ASYMMETRIC_PEER ||
+	    lgr->type =3D=3D SMC_LGR_SINGLE && lgr->max_links <=3D 1)
+		goto free_qentry;

 	ini =3D kzalloc(sizeof(*ini), GFP_KERNEL);
 	if (!ini)
-		goto out;
+		goto free_qentry;

 	ini->vlan_id =3D lgr->vlan_id;
 	smc_pnet_find_alt_roce(lgr, ini, link->smcibdev);
@@ -1190,6 +1188,7 @@ static void smc_llc_cli_add_link_invite(struct smc_l=
ink *link,
 			      ini->ib_gid, NULL, SMC_LLC_REQ);
 out:
 	kfree(ini);
+free_qentry:
 	kfree(qentry);
 }

=2D-
2.43.0