Commit 186edf7e authored by Vratislav Bendel's avatar Vratislav Bendel Committed by Paul Moore
Browse files

selinux: fix double free of cond_list on error paths 



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: default avatarVratislav Bendel <vbendel@redhat.com>
[PM: fix line lengths in the description]
Signed-off-by: default avatarPaul Moore <paul@paul-moore.com>
parent e783362e

security/selinux/ss/conditional.c

+2 −1
Original line number Diff line number Diff line
@@ -152,6 +152,8 @@ static void cond_list_destroy(struct policydb *p) 
	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)
@@ -441,7 +443,6 @@ int cond_read_list(struct policydb *p, void *fp) 
	return 0;

err:

	cond_list_destroy(p);

	p->cond_list = NULL;

	return rc;

}