[PATCH 5.18 0178/1095] selinux: fix memleak in security_read_state_kernel()

From: Greg Kroah-Hartman
Date: Mon Aug 15 2022 - 16:33:02 EST


From: Xiu Jianfeng <xiujianfeng@xxxxxxxxxx>

[ Upstream commit 73de1befcc53a7c68b0c5e76b9b5ac41c517760f ]

In this function, it directly returns the result of __security_read_policy
without freeing the allocated memory in *data, cause memory leak issue,
so free the memory if __security_read_policy failed.

Signed-off-by: Xiu Jianfeng <xiujianfeng@xxxxxxxxxx>
[PM: subject line tweak]
Signed-off-by: Paul Moore <paul@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
security/selinux/ss/services.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index 6901dc07680d..cad54f454d01 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -4049,6 +4049,7 @@ int security_read_policy(struct selinux_state *state,
int security_read_state_kernel(struct selinux_state *state,
void **data, size_t *len)
{
+ int err;
struct selinux_policy *policy;

policy = rcu_dereference_protected(
@@ -4061,5 +4062,11 @@ int security_read_state_kernel(struct selinux_state *state,
if (!*data)
return -ENOMEM;

- return __security_read_policy(policy, *data, len);
+ err = __security_read_policy(policy, *data, len);
+ if (err) {
+ vfree(*data);
+ *data = NULL;
+ *len = 0;
+ }
+ return err;
}
--
2.35.1