Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Pavel Skripkin <paskripkin@gmail.com>
To:     paul@paul-moore.com, davem@davemloft.net, yoshfuji@linux-ipv6.org,
        dsahern@kernel.org, kuba@kernel.org
Cc:     netdev@vger.kernel.org, linux-security-module@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Pavel Skripkin <paskripkin@gmail.com>,
        syzbot+cdd51ee2e6b0b2e18c0d@syzkaller.appspotmail.com
Subject: [PATCH 1/2] net: cipso: fix warnings in netlbl_cipsov4_add_std
Date:   Sat, 10 Jul 2021 10:03:13 +0300
Message-Id: <53de0ccd1aa3fffa6bce2a2ae7a5ca07e0af6d3a.1625900431.git.paskripkin@gmail.com>
In-Reply-To: <cover.1625900431.git.paskripkin@gmail.com>
References: <cover.1625900431.git.paskripkin@gmail.com>
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Precedence: bulk

Syzbot reported warning in netlbl_cipsov4_add(). The
problem was in too big doi_def->map.std->lvl.local_size
passed to kcalloc(). Since this value comes from userpace there is
no need to warn if value is not correct.

The same problem may occur with other kcalloc() calls in
this function, so, I've added __GFP_NOWARN flag to all
kcalloc() calls there.

Reported-and-tested-by: syzbot+cdd51ee2e6b0b2e18c0d@syzkaller.appspotmail.com
Fixes: 96cb8e3313c7 ("[NetLabel]: CIPSOv4 and Unlabeled packet integration")
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
---
 net/netlabel/netlabel_cipso_v4.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/netlabel/netlabel_cipso_v4.c b/net/netlabel/netlabel_cipso_v4.c
index 4f50a64315cf..50f40943c815 100644
--- a/net/netlabel/netlabel_cipso_v4.c
+++ b/net/netlabel/netlabel_cipso_v4.c
@@ -187,14 +187,14 @@ static int netlbl_cipsov4_add_std(struct genl_info *info,
 		}
 	doi_def->map.std->lvl.local = kcalloc(doi_def->map.std->lvl.local_size,
 					      sizeof(u32),
-					      GFP_KERNEL);
+					      GFP_KERNEL | __GFP_NOWARN);
 	if (doi_def->map.std->lvl.local == NULL) {
 		ret_val = -ENOMEM;
 		goto add_std_failure;
 	}
 	doi_def->map.std->lvl.cipso = kcalloc(doi_def->map.std->lvl.cipso_size,
 					      sizeof(u32),
-					      GFP_KERNEL);
+					      GFP_KERNEL | __GFP_NOWARN);
 	if (doi_def->map.std->lvl.cipso == NULL) {
 		ret_val = -ENOMEM;
 		goto add_std_failure;
@@ -263,7 +263,7 @@ static int netlbl_cipsov4_add_std(struct genl_info *info,
 		doi_def->map.std->cat.local = kcalloc(
 					      doi_def->map.std->cat.local_size,
 					      sizeof(u32),
-					      GFP_KERNEL);
+					      GFP_KERNEL | __GFP_NOWARN);
 		if (doi_def->map.std->cat.local == NULL) {
 			ret_val = -ENOMEM;
 			goto add_std_failure;
@@ -271,7 +271,7 @@ static int netlbl_cipsov4_add_std(struct genl_info *info,
 		doi_def->map.std->cat.cipso = kcalloc(
 					      doi_def->map.std->cat.cipso_size,
 					      sizeof(u32),
-					      GFP_KERNEL);
+					      GFP_KERNEL | __GFP_NOWARN);
 		if (doi_def->map.std->cat.cipso == NULL) {
 			ret_val = -ENOMEM;
 			goto add_std_failure;
-- 
2.32.0