62 lines
2.1 KiB
Diff
62 lines
2.1 KiB
Diff
From a4c22009a465ebe5fd0c09699e61ad0423b8849d Mon Sep 17 00:00:00 2001
|
|
From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= <philmd@redhat.com>
|
|
Date: Fri, 6 Sep 2019 14:00:34 +0100
|
|
Subject: [PATCH 07/22] Using ip_deq after m_free might read pointers from an
|
|
allocation reuse.
|
|
MIME-Version: 1.0
|
|
Content-Type: text/plain; charset=UTF-8
|
|
Content-Transfer-Encoding: 8bit
|
|
|
|
RH-Author: Philippe Mathieu-Daudé <philmd@redhat.com>
|
|
Message-id: <20190906140034.19722-2-philmd@redhat.com>
|
|
Patchwork-id: 90306
|
|
O-Subject: [RHEL-7.7 qemu-kvm-ma + RHEL-7.7 qemu-kvm-rhev + RHEL-8.1.0 qemu-kvm PATCH 1/1] Using ip_deq after m_free might read pointers from an allocation reuse.
|
|
Bugzilla: 1749724
|
|
RH-Acked-by: Thomas Huth <thuth@redhat.com>
|
|
RH-Acked-by: Stefano Garzarella <sgarzare@redhat.com>
|
|
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
|
|
|
|
From: Samuel Thibault <samuel.thibault@ens-lyon.org>
|
|
|
|
This would be difficult to exploit, but that is still related with
|
|
CVE-2019-14378 which generates fragmented IP packets that would trigger this
|
|
issue and at least produce a DoS.
|
|
|
|
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
|
|
(cherry picked from libslirp commit c59279437eda91841b9d26079c70b8a540d41204)
|
|
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
|
|
|
|
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
|
|
---
|
|
slirp/ip_input.c | 6 ++++--
|
|
1 file changed, 4 insertions(+), 2 deletions(-)
|
|
|
|
diff --git a/slirp/ip_input.c b/slirp/ip_input.c
|
|
index 07d8808..7cf0133 100644
|
|
--- a/slirp/ip_input.c
|
|
+++ b/slirp/ip_input.c
|
|
@@ -300,6 +300,7 @@ ip_reass(Slirp *slirp, struct ip *ip, struct ipq *fp)
|
|
*/
|
|
while (q != (struct ipasfrag*)&fp->frag_link &&
|
|
ip->ip_off + ip->ip_len > q->ipf_off) {
|
|
+ struct ipasfrag *prev;
|
|
i = (ip->ip_off + ip->ip_len) - q->ipf_off;
|
|
if (i < q->ipf_len) {
|
|
q->ipf_len -= i;
|
|
@@ -307,9 +308,10 @@ ip_reass(Slirp *slirp, struct ip *ip, struct ipq *fp)
|
|
m_adj(dtom(slirp, q), i);
|
|
break;
|
|
}
|
|
+ prev = q;
|
|
q = q->ipf_next;
|
|
- m_free(dtom(slirp, q->ipf_prev));
|
|
- ip_deq(q->ipf_prev);
|
|
+ ip_deq(prev);
|
|
+ m_free(dtom(slirp, prev));
|
|
}
|
|
|
|
insert:
|
|
--
|
|
1.8.3.1
|
|
|