30 lines
1.1 KiB
Diff
30 lines
1.1 KiB
Diff
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References: CVE-2012-4539 XSA-24 bnc#786520
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compat/gnttab: Prevent infinite loop in compat code
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c/s 20281:95ea2052b41b, which introduces Grant Table version 2
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hypercalls introduces a vulnerability whereby the compat hypercall
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handler can fall into an infinite loop.
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If the watchdog is enabled, Xen will die after the timeout.
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This is a security problem, XSA-24 / CVE-2012-4539.
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Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
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Acked-by: Jan Beulich <jbeulich@suse.com>
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Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
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Index: xen-4.2.0-testing/xen/common/compat/grant_table.c
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===================================================================
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--- xen-4.2.0-testing.orig/xen/common/compat/grant_table.c
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+++ xen-4.2.0-testing/xen/common/compat/grant_table.c
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@@ -318,6 +318,8 @@ int compat_grant_table_op(unsigned int c
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#undef XLAT_gnttab_get_status_frames_HNDL_frame_list
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if ( unlikely(__copy_to_guest(cmp_uop, &cmp.get_status, 1)) )
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rc = -EFAULT;
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+ else
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+ i = 1;
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}
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break;
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}
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