[PATCH 5.18 0179/1095] selinux: Add boundary check in put_entry()

From: Greg Kroah-Hartman
Date: Mon Aug 15 2022 - 16:33:06 EST


From: Xiu Jianfeng <xiujianfeng@xxxxxxxxxx>

[ Upstream commit 15ec76fb29be31df2bccb30fc09875274cba2776 ]

Just like next_entry(), boundary check is necessary to prevent memory
out-of-bound access.

Signed-off-by: Xiu Jianfeng <xiujianfeng@xxxxxxxxxx>
Signed-off-by: Paul Moore <paul@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
security/selinux/ss/policydb.h | 2 ++
1 file changed, 2 insertions(+)

diff --git a/security/selinux/ss/policydb.h b/security/selinux/ss/policydb.h
index c24d4e1063ea..ffc4e7bad205 100644
--- a/security/selinux/ss/policydb.h
+++ b/security/selinux/ss/policydb.h
@@ -370,6 +370,8 @@ static inline int put_entry(const void *buf, size_t bytes, int num, struct polic
{
size_t len = bytes * num;

+ if (len > fp->len)
+ return -EINVAL;
memcpy(fp->data, buf, len);
fp->data += len;
fp->len -= len;
--
2.35.1