aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorJan Beulich <jbeulich@suse.com>2013-10-22 12:06:43 +0200
committerJan Beulich <jbeulich@suse.com>2013-10-22 12:06:43 +0200
commitf17eab34ef3d53920816771f4ab5f907160e6ca6 (patch)
treee81fcb60e20ce80ee81988d0c2ebaf698fe1e196
parent0f72e5d7608e01a79f26a8601a3ea289fa52589f (diff)
downloadxen-f17eab34ef3d53920816771f4ab5f907160e6ca6.tar.gz
xen-f17eab34ef3d53920816771f4ab5f907160e6ca6.tar.bz2
xen-f17eab34ef3d53920816771f4ab5f907160e6ca6.zip
x86: add address validity check to guest_map_l1e()
Just like for guest_get_eff_l1e() this prevents accessing as page tables (and with the wrong memory attribute) internal data inside Xen happening to be mapped with 1Gb pages. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper@citrix.com> Acked-by: Keir Fraser <keir@xen.org> master commit: d06a0d715ec1423b6c42141ab1b0ff69a3effb56 master date: 2013-10-11 09:29:43 +0200
-rw-r--r--xen/include/asm-x86/paging.h3
1 files changed, 2 insertions, 1 deletions
diff --git a/xen/include/asm-x86/paging.h b/xen/include/asm-x86/paging.h
index ee35dff865..60335ed756 100644
--- a/xen/include/asm-x86/paging.h
+++ b/xen/include/asm-x86/paging.h
@@ -382,7 +382,8 @@ guest_map_l1e(struct vcpu *v, unsigned long addr, unsigned long *gl1mfn)
return paging_get_hostmode(v)->guest_map_l1e(v, addr, gl1mfn);
/* Find this l1e and its enclosing l1mfn in the linear map */
- if ( __copy_from_user(&l2e,
+ if ( !__addr_ok(addr) ||
+ __copy_from_user(&l2e,
&__linear_l2_table[l2_linear_offset(addr)],
sizeof(l2_pgentry_t)) != 0 )
return NULL;