[PATCH 1/1] selinux: add the processing of the failure of avc_add_xperms_decision()

From: thunder . leizhen
Date: Wed Aug 07 2024 - 05:03:01 EST


From: Zhen Lei <thunder.leizhen@xxxxxxxxxx>

When avc_add_xperms_decision() fails, the information recorded by the new
avc node is incomplete. In this case, the new avc node should be released
instead of replacing the old avc node.

Fixes: fa1aa143ac4a ("selinux: extended permissions for ioctls")
Suggested-by: Stephen Smalley <stephen.smalley.work@xxxxxxxxx>
Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
---
security/selinux/avc.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index 7087cd2b802d8d8..b49c44869dc4627 100644
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -907,7 +907,11 @@ static int avc_update_node(u32 event, u32 perms, u8 driver, u8 xperm, u32 ssid,
node->ae.avd.auditdeny &= ~perms;
break;
case AVC_CALLBACK_ADD_XPERMS:
- avc_add_xperms_decision(node, xpd);
+ rc = avc_add_xperms_decision(node, xpd);
+ if (rc) {
+ avc_node_kill(node);
+ goto out_unlock;
+ }
break;
}
avc_node_replace(node, orig);
--
2.34.1