[PATCH 6.18 09/13] apparmor: Fix double free of ns_name in aa_replace_profiles()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

6.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: John Johansen <john.johansen@canonical.com>

commit 5df0c44e8f5f619d3beb871207aded7c78414502 upstream.

if ns_name is NULL after
1071         error = aa_unpack(udata, &lh, &ns_name);

and if ent->ns_name contains an ns_name in
1089                 } else if (ent->ns_name) {

then ns_name is assigned the ent->ns_name
1095                         ns_name = ent->ns_name;

however ent->ns_name is freed at
1262                 aa_load_ent_free(ent);

and then again when freeing ns_name at
1270         kfree(ns_name);

Fix this by NULLing out ent->ns_name after it is transferred to ns_name

Fixes: 145a0ef21c8e9 ("apparmor: fix blob compression when ns is forced on a policy load
")
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Reviewed-by: Cengiz Can <cengiz.can@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 security/apparmor/policy.c |    1 +
 1 file changed, 1 insertion(+)

--- a/security/apparmor/policy.c
+++ b/security/apparmor/policy.c
@@ -1149,6 +1149,7 @@ ssize_t aa_replace_profiles(struct aa_ns
 				goto fail;
 			}
 			ns_name = ent->ns_name;
+			ent->ns_name = NULL;
 		} else
 			count++;
 	}