| From 186edf7e368c40d06cf727a1ad14698ea67b74ad Mon Sep 17 00:00:00 2001 |
| From: Vratislav Bendel <vbendel@redhat.com> |
| Date: Wed, 2 Feb 2022 12:25:11 +0100 |
| Subject: selinux: fix double free of cond_list on error paths |
| |
| From: Vratislav Bendel <vbendel@redhat.com> |
| |
| commit 186edf7e368c40d06cf727a1ad14698ea67b74ad upstream. |
| |
| On error path from cond_read_list() and duplicate_policydb_cond_list() |
| the cond_list_destroy() gets called a second time in caller functions, |
| resulting in NULL pointer deref. Fix this by resetting the |
| cond_list_len to 0 in cond_list_destroy(), making subsequent calls a |
| noop. |
| |
| Also consistently reset the cond_list pointer to NULL after freeing. |
| |
| Cc: stable@vger.kernel.org |
| Signed-off-by: Vratislav Bendel <vbendel@redhat.com> |
| [PM: fix line lengths in the description] |
| Signed-off-by: Paul Moore <paul@paul-moore.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| security/selinux/ss/conditional.c | 3 ++- |
| 1 file changed, 2 insertions(+), 1 deletion(-) |
| |
| --- a/security/selinux/ss/conditional.c |
| +++ b/security/selinux/ss/conditional.c |
| @@ -152,6 +152,8 @@ static void cond_list_destroy(struct pol |
| for (i = 0; i < p->cond_list_len; i++) |
| cond_node_destroy(&p->cond_list[i]); |
| kfree(p->cond_list); |
| + p->cond_list = NULL; |
| + p->cond_list_len = 0; |
| } |
| |
| void cond_policydb_destroy(struct policydb *p) |
| @@ -440,7 +442,6 @@ int cond_read_list(struct policydb *p, v |
| return 0; |
| err: |
| cond_list_destroy(p); |
| - p->cond_list = NULL; |
| return rc; |
| } |
| |