blob: 32be89fe6411dbea858d0443bf8974955d1e33a0 [file] [log] [blame]
From 86936fb98ce9762f08984090005b43d4e2d0bd8d Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Thu, 23 Jul 2020 18:23:05 +0300
Subject: Smack: prevent underflow in smk_set_cipso()
From: Dan Carpenter <dan.carpenter@oracle.com>
[ Upstream commit 42a2df3e829f3c5562090391b33714b2e2e5ad4a ]
We have an upper bound on "maplevel" but forgot to check for negative
values.
Fixes: e114e473771c ("Smack: Simplified Mandatory Access Control Kernel")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
security/smack/smackfs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c
index 2bae1fc493d16..9c4308077574c 100644
--- a/security/smack/smackfs.c
+++ b/security/smack/smackfs.c
@@ -884,7 +884,7 @@ static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
}
ret = sscanf(rule, "%d", &maplevel);
- if (ret != 1 || maplevel > SMACK_CIPSO_MAXLEVEL)
+ if (ret != 1 || maplevel < 0 || maplevel > SMACK_CIPSO_MAXLEVEL)
goto out;
rule += SMK_DIGITLEN;
--
2.25.1