diff mbox series

smackfs: Prevent underflow in smk_set_cipso()

Message ID 5070f3eb-55e2-44db-a97d-41f9b9878c6d@moroto.mountain
State New
Headers
Series smackfs: Prevent underflow in smk_set_cipso() |

Commit Message

Dan Carpenter July 6, 2023, 5:52 a.m. UTC 
  There is a upper bound to "catlen" but no lower bound to prevent
negatives.  I don't see that this necessarily causes a problem but we
may as well be safe.

Fixes: e114e473771c ("Smack: Simplified Mandatory Access Control Kernel")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
---
 security/smack/smackfs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c
index 5590eaad241b..25f67d1b5c73 100644
--- a/security/smack/smackfs.c
+++ b/security/smack/smackfs.c
@@ -896,7 +896,7 @@  static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
 	}
 
 	ret = sscanf(rule, "%d", &catlen);
-	if (ret != 1 || catlen > SMACK_CIPSO_MAXCATNUM)
+	if (ret != 1 || catlen < 0 || catlen > SMACK_CIPSO_MAXCATNUM)
 		goto out;
 
 	if (format == SMK_FIXED24_FMT &&