From: Ian Campbell <ian.campbell@citrix.com>
Date: Mon, 23 Jul 2012 12:09:38 +0000 (+0100)
Subject: libxc: restore: bounds check for start_info.{store_mfn,console.domU.mfn}
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~8177
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=c8c7017f064d03623c02a61fa35be6720591be90;p=xen.git

libxc: restore: bounds check for start_info.{store_mfn,console.domU.mfn}

These fields are canonicalised by the guest on suspend and therefore must be
valid pfns during restore.

Reported-by: Jonathan Ludlam <Jonathan.Ludlam@eu.citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
---

diff --git a/tools/libxc/xc_domain_restore.c b/tools/libxc/xc_domain_restore.c
index 6227d43ffd..3fe2b12373 100644
--- a/tools/libxc/xc_domain_restore.c
+++ b/tools/libxc/xc_domain_restore.c
@@ -1912,9 +1912,21 @@ int xc_domain_restore(xc_interface *xch, int io_fd, uint32_t dom,
             SET_FIELD(start_info, nr_pages, dinfo->p2m_size);
             SET_FIELD(start_info, shared_info, shared_info_frame<<PAGE_SHIFT);
             SET_FIELD(start_info, flags, 0);
+            if ( GET_FIELD(start_info, store_mfn) > dinfo->p2m_size )
+            {
+                ERROR("Suspend record xenstore frame number is bad");
+                munmap(start_info, PAGE_SIZE);
+                goto out;
+            }
             *store_mfn = ctx->p2m[GET_FIELD(start_info, store_mfn)];
             SET_FIELD(start_info, store_mfn, *store_mfn);
             SET_FIELD(start_info, store_evtchn, store_evtchn);
+            if ( GET_FIELD(start_info, console.domU.mfn) > dinfo->p2m_size )
+            {
+                ERROR("Suspend record console frame number is bad");
+                munmap(start_info, PAGE_SIZE);
+                goto out;
+            }
             *console_mfn = ctx->p2m[GET_FIELD(start_info, console.domU.mfn)];
             SET_FIELD(start_info, console.domU.mfn, *console_mfn);
             SET_FIELD(start_info, console.domU.evtchn, console_evtchn);