qemu: CVE-2018-11806 slirp heap buffer overflow

(From OE-Core rev: c03cef42e079e4ed3d1e4f401722778157158bd6)

Signed-off-by: Jeremy Puhlman <jpuhlman@mvista.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 71 insertions, 0 deletions

diff --git a/meta/recipes-devtools/qemu/qemu/0001-CVE-2018-11806-QEMU-slirp-heap-buffer-overflow.patch b/meta/recipes-devtools/qemu/qemu/0001-CVE-2018-11806-QEMU-slirp-heap-buffer-overflow.patch
new file mode 100644
index 0000000000..837b65a79a
--- /dev/null
+++ b/meta/recipes-devtools/qemu/qemu/0001-CVE-2018-11806-QEMU-slirp-heap-buffer-overflow.patch
@@ -0,0 +1,70 @@
+CVE: CVE-2018-11806
+Upstream-Status: Backport
+
+https://lists.gnu.org/archive/html/qemu-devel/2018-06/msg01012.html
+
+From dc21a9d2951f0a2a7e63633e2b5c68c54e4edc4b Mon Sep 17 00:00:00 2001
+From: Jeremy Puhlman <jpuhlman@mvista.com>
+Date: Thu, 14 Jun 2018 01:28:49 +0000
+Subject: [PATCH] CVE-2018-11806 QEMU: slirp: heap buffer overflow
+
+Subject: [Qemu-devel] [PATCH 1/2] slirp: correct size computation while concatenating mbuf
+Date:   Tue, 5 Jun 2018 23:38:35 +0530
+From: Prasad J Pandit <address@hidden>
+
+While reassembling incoming fragmented datagrams, 'm_cat' routine
+extends the 'mbuf' buffer, if it has insufficient room. It computes
+a wrong buffer size, which leads to overwriting adjacent heap buffer
+area. Correct this size computation in m_cat.
+
+Reported-by: ZDI Disclosures <address@hidden>
+Signed-off-by: Prasad J Pandit <address@hidden>
+---
+ slirp/mbuf.c | 8 ++++----
+ 1 file changed, 4 insertions(+), 4 deletions(-)
+
+Signed-off-by: Jeremy Puhlman <jpuhlman@mvista.com>
+---
+ slirp/mbuf.c | 8 ++++----
+ 1 file changed, 4 insertions(+), 4 deletions(-)
+
+diff --git a/slirp/mbuf.c b/slirp/mbuf.c
+index 5ff2455..7fb4501 100644
+--- a/slirp/mbuf.c
++++ b/slirp/mbuf.c
+@@ -138,7 +138,7 @@ m_cat(struct mbuf *m, struct mbuf *n)
+         * If there's no room, realloc
+         */
+        if (M_FREEROOM(m) < n->m_len)
+-               m_inc(m,m->m_size+MINCSIZE);
++               m_inc(m, m->m_len + n->m_len);
+ 
+        memcpy(m->m_data+m->m_len, n->m_data, n->m_len);
+        m->m_len += n->m_len;
+@@ -158,12 +158,12 @@ m_inc(struct mbuf *m, int size)
+ 
+         if (m->m_flags & M_EXT) {
+          datasize = m->m_data - m->m_ext;
+-          m->m_ext = g_realloc(m->m_ext, size);
++          m->m_ext = g_realloc(m->m_ext, size + datasize);
+          m->m_data = m->m_ext + datasize;
+         } else {
+          char *dat;
+          datasize = m->m_data - m->m_dat;
+-          dat = g_malloc(size);
++          dat = g_malloc(size + datasize);
+          memcpy(dat, m->m_dat, m->m_size);
+ 
+          m->m_ext = dat;
+@@ -171,7 +171,7 @@ m_inc(struct mbuf *m, int size)
+          m->m_flags |= M_EXT;
+         }
+ 
+-        m->m_size = size;
++        m->m_size = size + datasize;
+ 
+ }
+ 
+-- 
+2.13.3
+
diff --git a/meta/recipes-devtools/qemu/qemu_2.12.0.bb b/meta/recipes-devtools/qemu/qemu_2.12.0.bb
index 21796df9d7..98db44a8ef 100644
--- a/meta/recipes-devtools/qemu/qemu_2.12.0.bb
+++ b/meta/recipes-devtools/qemu/qemu_2.12.0.bb
@@ -21,6 +21,7 @@ SRC_URI = "http://wiki.qemu-project.org/download/${BP}.tar.bz2 \
            file://0009-apic-fixup-fallthrough-to-PIC.patch \
            file://0010-linux-user-Fix-webkitgtk-hangs-on-32-bit-x86-target.patch \
            file://0011-Revert-linux-user-fix-mmap-munmap-mprotect-mremap-sh.patch \
+           file://0001-CVE-2018-11806-QEMU-slirp-heap-buffer-overflow.patch \
            "
 UPSTREAM_CHECK_REGEX = "qemu-(?P<pver>\d+\..*)\.tar"