From 04f34e76ac50acaeaf9758225a9678e91e4297ec Mon Sep 17 00:00:00 2001 From: Andrew Cooper Date: Thu, 30 Mar 2017 17:32:33 +0100 Subject: [PATCH] tools/python: Adjust migration v2 library to warn about zero-content records These records shouldn't be in a stream, but accidentally are. Warn about them, but don't abort the verification. While here, add a missing length check to the X86_PV_P2M_FRAMES record checker. Signed-off-by: Andrew Cooper Reviewed-by: Wei Liu --- tools/python/xen/migration/libxc.py | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/tools/python/xen/migration/libxc.py b/tools/python/xen/migration/libxc.py index 6fd3f6dcdf..f24448a9ef 100644 --- a/tools/python/xen/migration/libxc.py +++ b/tools/python/xen/migration/libxc.py @@ -312,6 +312,10 @@ class VerifyLibxc(VerifyBase): def verify_record_x86_pv_p2m_frames(self, content): """ x86 PV p2m frames record """ + if len(content) < 8: + raise RecordError("x86_pv_p2m_frames: record length must be at" + " least 8 bytes long") + if len(content) % 8 != 0: raise RecordError("Length expected to be a multiple of 8, not %d" % (len(content), )) @@ -324,10 +328,14 @@ class VerifyLibxc(VerifyBase): """ Generic for all REC_TYPE_x86_pv_vcpu_{basic,extended,xsave,msrs} """ minsz = calcsize(X86_PV_VCPU_HDR_FORMAT) - if len(content) <= minsz: + if len(content) < minsz: raise RecordError("X86_PV_VCPU_%s record length must be at least %d" " bytes long" % (name, minsz)) + if len(content) == minsz: + self.info("Warning: X86_PV_VCPU_%s record with zero content" + % (name, )) + vcpuid, res1 = unpack(X86_PV_VCPU_HDR_FORMAT, content[:minsz]) if res1 != 0: @@ -385,6 +393,9 @@ class VerifyLibxc(VerifyBase): if rsvd != 0: raise RecordError("Reserved field not zero (0x%04x)" % (rsvd, )) + if count == 0: + self.info("Warning: HVM_PARAMS record with zero content") + sz += count * calcsize(HVM_PARAMS_ENTRY_FORMAT) if len(content) != sz: -- 2.30.2