aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorIan Jackson <Ian.Jackson@eu.citrix.com>2012-11-14 11:46:07 +0000
committerIan Jackson <Ian.Jackson@eu.citrix.com>2012-11-14 11:46:07 +0000
commit45cc0581c6515105147fbc27339d056e02782efb (patch)
tree0b8e748adefa3f4d41977a5b7cfd57960153c891
parent33df3b4a744312c01a8fa9929f06d62a81f50c28 (diff)
downloadxen-45cc0581c6515105147fbc27339d056e02782efb.tar.gz
xen-45cc0581c6515105147fbc27339d056e02782efb.tar.bz2
xen-45cc0581c6515105147fbc27339d056e02782efb.zip
compat/gnttab: Prevent infinite loop in compat code
c/s 20281:95ea2052b41b, which introduces Grant Table version 2 hypercalls introduces a vulnerability whereby the compat hypercall handler can fall into an infinite loop. If the watchdog is enabled, Xen will die after the timeout. This is a security problem, XSA-24 / CVE-2012-4539. Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Acked-by: Jan Beulich <jbeulich@suse.com> Acked-by: Ian Jackson <ian.jackson@eu.citrix.com> Committed-by: Ian Jackson <ian.jackson@eu.citrix.com> xen-unstable changeset: 26151:b64a7d868f06 Backport-requested-by: security@xen.org Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
-rw-r--r--xen/common/compat/grant_table.c2
1 files changed, 2 insertions, 0 deletions
diff --git a/xen/common/compat/grant_table.c b/xen/common/compat/grant_table.c
index edd20c6bd3..32cd2bf5eb 100644
--- a/xen/common/compat/grant_table.c
+++ b/xen/common/compat/grant_table.c
@@ -318,6 +318,8 @@ int compat_grant_table_op(unsigned int cmd,
#undef XLAT_gnttab_get_status_frames_HNDL_frame_list
if ( unlikely(__copy_to_guest(cmp_uop, &cmp.get_status, 1)) )
rc = -EFAULT;
+ else
+ i = 1;
}
break;
}