From c232bc1f346a6af9777c216d01f7940898ae1650 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 19 Oct 2018 12:12:33 +0200 Subject: [PATCH] dhcp6: make sure we have enough space for the DHCP6 option header Fixes a vulnerability originally discovered by Felix Wilhelm from Google. CVE-2018-15688 LP: #1795921 https://bugzilla.redhat.com/show_bug.cgi?id=1639067 (cherry-picked from commit 4dac5eaba4e419b29c97da38a8b1f82336c2c892) Resolves: #1643363 --- src/libsystemd-network/dhcp6-option.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/libsystemd-network/dhcp6-option.c b/src/libsystemd-network/dhcp6-option.c index 18196b125..097949729 100644 --- a/src/libsystemd-network/dhcp6-option.c +++ b/src/libsystemd-network/dhcp6-option.c @@ -103,7 +103,7 @@ int dhcp6_option_append_ia(uint8_t **buf, size_t *buflen, DHCP6IA *ia) { return -EINVAL; } - if (*buflen < len) + if (*buflen < offsetof(DHCP6Option, data) + len) return -ENOBUFS; ia_hdr = *buf;