diff options
author | Jörg Frings-Fürst <debian@jff-webhosting.net> | 2017-10-02 07:00:36 +0200 |
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committer | Jörg Frings-Fürst <debian@jff-webhosting.net> | 2017-10-02 07:00:36 +0200 |
commit | 3804bc2606a92e2f2f4b3a2b043af0d77d92b386 (patch) | |
tree | ad5df7aa0b975693a09335d296ee56457ef6076e /debian/patches/CVE-2017-7508.patch | |
parent | 749384a154025e268b53cf3cc79eaeddde2b3ceb (diff) | |
parent | 678cfd249add7ca758e4c41933c7b730132c99f4 (diff) |
Merge branch 'stretch' of ssh://git.debian.org/git/collab-maint/openvpn into stretchstretch
Diffstat (limited to 'debian/patches/CVE-2017-7508.patch')
-rw-r--r-- | debian/patches/CVE-2017-7508.patch | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/debian/patches/CVE-2017-7508.patch b/debian/patches/CVE-2017-7508.patch new file mode 100644 index 0000000..6ba80ac --- /dev/null +++ b/debian/patches/CVE-2017-7508.patch @@ -0,0 +1,57 @@ +commit ed28cde3d8bf3f1459b2f42f0e27d64801009f92 +Author: Gert Doering <gert@greenie.muc.de> +Date: Tue Jun 13 22:08:32 2017 +0200 + + Fix remotely-triggerable ASSERT() on malformed IPv6 packet. + + Correct sanity checks on IPv6 packet length in mss_fixup_ipv6(), + and change the ASSERT() check in mss_fixup_dowork() into a simple + "return" (= the TCP header will simply not be inspected further). + + CVE-2017-7508 has been assigned due to the serious nature of the + bug: it can be used to remotely shutdown an openvpn server or + client, if IPv6 and --mssfix are enabled and the IPv6 networks used + inside the VPN are known. + + Found by Guido Vranken <guidovranken@gmail.com>. + + v2: style changes + + CVE: 2017-7508 + Signed-off-by: Gert Doering <gert@greenie.muc.de> + Acked-by: Steffan Karger <steffan.karger@fox-it.com> + Message-Id: <20170613200832.15027-1-gert@greenie.muc.de> + URL: https://www.mail-archive.com/search?l=mid&q=20170613200832.15027-1-gert@greenie.muc.de + Signed-off-by: Gert Doering <gert@greenie.muc.de> + (cherry picked from commit c3f47077a7756de5929094569421a95aa66f2022) + +Index: openvpn-2.4.0/src/openvpn/mss.c +=================================================================== +--- openvpn-2.4.0.orig/src/openvpn/mss.c ++++ openvpn-2.4.0/src/openvpn/mss.c +@@ -120,8 +120,12 @@ mss_fixup_ipv6(struct buffer *buf, int m + return; + } + ++ /* skip IPv6 header (40 bytes), ++ * verify remainder is large enough to contain a full TCP header ++ */ + newbuf = *buf; +- if (buf_advance( &newbuf, 40 ) ) ++ if (buf_advance( &newbuf, 40 ) ++ && BLEN(&newbuf) >= (int) sizeof(struct openvpn_tcphdr)) + { + struct openvpn_tcphdr *tc = (struct openvpn_tcphdr *) BPTR(&newbuf); + if (tc->flags & OPENVPN_TCPH_SYN_MASK) +@@ -145,7 +149,10 @@ mss_fixup_dowork(struct buffer *buf, uin + int accumulate; + struct openvpn_tcphdr *tc; + +- ASSERT(BLEN(buf) >= (int) sizeof(struct openvpn_tcphdr)); ++ if (BLEN(buf) < (int) sizeof(struct openvpn_tcphdr)) ++ { ++ return; ++ } + + verify_align_4(buf); + tc = (struct openvpn_tcphdr *) BPTR(buf); |