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From: P J P <ppandit@redhat.com>
Date: Mon, 17 Jul 2017 17:33:26 +0530
Message-Id: <20170717120326.27967-1-ppandit@redhat.com>
Subject: slirp: check len against dhcp options array end
Bug-Debian: http://bugs.debian.org/869171
While parsing dhcp options string in 'dhcp_decode', if an options'
length 'len' appeared towards the end of 'bp_vend' array, ensuing
read could lead to an OOB memory access issue. Add check to avoid it.
Reported-by: Reno Robert <renorobert@gmail.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
---
slirp/bootp.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/slirp/bootp.c b/slirp/bootp.c
index 5a4646c..5dd1a41 100644
--- a/slirp/bootp.c
+++ b/slirp/bootp.c
@@ -123,6 +123,9 @@ static void dhcp_decode(const struct bootp_t *bp, int *pmsg_type,
if (p >= p_end)
break;
len = *p++;
+ if (p + len > p_end) {
+ break;
+ }
DPRINTF("dhcp: tag=%d len=%d\n", tag, len);
switch(tag) {
--
2.9.4
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