From: Andrew Cooper <andrew.cooper3@citrix.com>
To: Xen-devel <xen-devel@lists.xen.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>,
Jan Beulich <JBeulich@suse.com>
Subject: [PATCH v3 08/24] x86/emul: Correct the behaviour of pop %ss and interrupt shadowing
Date: Wed, 30 Nov 2016 13:50:25 +0000 [thread overview]
Message-ID: <1480513841-7565-9-git-send-email-andrew.cooper3@citrix.com> (raw)
In-Reply-To: <1480513841-7565-1-git-send-email-andrew.cooper3@citrix.com>
The mov_ss retire flag should only be set once load_seg() has returned
success. In particular, it should not be set if an exception occured when
trying to load %ss.
_hvm_emulate_one(), currently the sole user of mov_ss, only consideres it in
the case that x86_emulate() returns X86EMUL_OKAY, so this bug isn't actually
exposed to guests.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
CC: Jan Beulich <JBeulich@suse.com>
v3:
* New
---
xen/arch/x86/x86_emulate/x86_emulate.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/xen/arch/x86/x86_emulate/x86_emulate.c b/xen/arch/x86/x86_emulate/x86_emulate.c
index 416812e..bacdee6 100644
--- a/xen/arch/x86/x86_emulate/x86_emulate.c
+++ b/xen/arch/x86/x86_emulate/x86_emulate.c
@@ -2656,6 +2656,8 @@ x86_emulate(
&dst.val, op_bytes, ctxt, ops)) != 0 ||
(rc = load_seg(src.val, dst.val, 0, NULL, ctxt, ops)) != 0 )
goto done;
+ if ( src.val == x86_seg_ss )
+ ctxt->retire.mov_ss = 1;
break;
case 0x0e: /* push %%cs */
@@ -2668,7 +2670,6 @@ x86_emulate(
case 0x17: /* pop %%ss */
src.val = x86_seg_ss;
- ctxt->retire.mov_ss = 1;
goto pop_seg;
case 0x1e: /* push %%ds */
--
2.1.4
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next prev parent reply other threads:[~2016-11-30 13:50 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-30 13:50 [PATCH for-4.9 v3 00/24] XSA-191 followup Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 01/24] x86/shadow: Fix #PFs from emulated writes crossing a page boundary Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 02/24] x86/emul: Drop X86EMUL_CMPXCHG_FAILED Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 03/24] x86/emul: Simplfy emulation state setup Andrew Cooper
2016-12-08 6:34 ` George Dunlap
2016-11-30 13:50 ` [PATCH v3 04/24] x86/emul: Rename hvm_trap to x86_event and move it into the emulation infrastructure Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 05/24] x86/emul: Rename HVM_DELIVER_NO_ERROR_CODE to X86_EVENT_NO_EC Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 06/24] x86/pv: Implement pv_inject_{event, page_fault, hw_exception}() Andrew Cooper
2016-12-01 10:06 ` Jan Beulich
2016-11-30 13:50 ` [PATCH v3 07/24] x86/emul: Clean up the naming of the retire union Andrew Cooper
2016-11-30 13:58 ` Paul Durrant
2016-11-30 14:02 ` Andrew Cooper
2016-11-30 14:05 ` Paul Durrant
2016-11-30 16:43 ` Jan Beulich
2016-12-01 10:08 ` Jan Beulich
2016-11-30 13:50 ` Andrew Cooper [this message]
2016-12-01 10:18 ` [PATCH v3 08/24] x86/emul: Correct the behaviour of pop %ss and interrupt shadowing Jan Beulich
2016-12-01 10:51 ` Andrew Cooper
2016-12-01 11:19 ` Jan Beulich
2016-11-30 13:50 ` [PATCH v3 09/24] x86/emul: Provide a wrapper to x86_emulate() to ASSERT() certain behaviour Andrew Cooper
2016-12-01 10:40 ` Jan Beulich
2016-12-01 10:58 ` Andrew Cooper
2016-12-01 11:21 ` Jan Beulich
2016-11-30 13:50 ` [PATCH v3 10/24] x86/emul: Always use fault semantics for software events Andrew Cooper
2016-11-30 17:55 ` Boris Ostrovsky
2016-12-01 10:53 ` Jan Beulich
2016-12-01 11:15 ` Andrew Cooper
2016-12-01 11:23 ` Jan Beulich
2016-11-30 13:50 ` [PATCH v3 11/24] x86/emul: Implement singlestep as a retire flag Andrew Cooper
2016-11-30 14:28 ` Paul Durrant
2016-12-01 11:16 ` Jan Beulich
2016-12-01 11:23 ` Andrew Cooper
2016-12-01 11:33 ` Tim Deegan
2016-12-01 12:05 ` Jan Beulich
2016-11-30 13:50 ` [PATCH v3 12/24] x86/emul: Remove opencoded exception generation Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 13/24] x86/emul: Rework emulator event injection Andrew Cooper
2016-11-30 14:26 ` Paul Durrant
2016-12-01 11:35 ` Tim Deegan
2016-12-01 12:31 ` Jan Beulich
2016-11-30 13:50 ` [PATCH v3 14/24] x86/vmx: Use hvm_{get, set}_segment_register() rather than vmx_{get, set}_segment_register() Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 15/24] x86/hvm: Reposition the modification of raw segment data from the VMCB/VMCS Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 16/24] x86/emul: Avoid raising faults behind the emulators back Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 17/24] x86/pv: " Andrew Cooper
2016-12-01 11:50 ` Tim Deegan
2016-12-01 12:57 ` Jan Beulich
2016-12-01 13:12 ` Andrew Cooper
2016-12-01 13:27 ` Jan Beulich
2016-11-30 13:50 ` [PATCH v3 18/24] x86/shadow: " Andrew Cooper
2016-12-01 11:39 ` Tim Deegan
2016-12-01 11:40 ` Andrew Cooper
2016-12-01 13:00 ` Jan Beulich
2016-12-01 13:15 ` Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 19/24] x86/hvm: Extend the hvm_copy_*() API with a pagefault_info pointer Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 20/24] x86/hvm: Reimplement hvm_copy_*_nofault() in terms of no pagefault_info Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 21/24] x86/hvm: Rename hvm_copy_*_guest_virt() to hvm_copy_*_guest_linear() Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 22/24] x86/hvm: Avoid __hvm_copy() raising #PF behind the emulators back Andrew Cooper
2016-11-30 14:29 ` Paul Durrant
2016-11-30 13:50 ` [PATCH v3 23/24] x86/emul: Prepare to allow use of system segments for memory references Andrew Cooper
2016-11-30 13:50 ` [PATCH v3 24/24] x86/emul: Use system-segment relative memory accesses Andrew Cooper
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