{"id":793,"date":"2012-02-02T17:27:20","date_gmt":"2012-02-02T09:27:20","guid":{"rendered":"http:\/\/notes.zerobox.org\/?p=793"},"modified":"2012-02-02T17:27:20","modified_gmt":"2012-02-02T09:27:20","slug":"%e6%a0%87%e5%87%86mdl%e6%96%b9%e6%b3%95%e4%bf%ae%e6%94%b9page%e3%80%81nonpage%e5%86%85%e5%ad%98%e7%9a%84%e5%b1%9e%e6%80%a7","status":"publish","type":"post","link":"http:\/\/zerobox.org\/notes\/793.html","title":{"rendered":"\u6807\u51c6MDL\u65b9\u6cd5\u4fee\u6539Page\u3001NonPage\u5185\u5b58\u7684\u5c5e\u6027~"},"content":{"rendered":"

\u6765\u6e90\uff1ahttp:\/\/hi.baidu.com\/%E5%8F%AB%E6%88%91v%E6%A0%A1\/blog\/item\/018a6000e7f80b1d738da5f6.html<\/a><\/p>\n

 <\/p>\n

typedef struct _REPROTECT_CONTEXT
\n{
\nPMDL\u00a0\u00a0 Mdl;
\nPUCHAR LockedVa;
\n} REPROTECT_CONTEXT, * PREPROTECT_CONTEXT;<\/p>\n

 <\/p>\n

NTSTATUS
\nMmLockVaForWrite(
\n__in PVOID Va,
\n__in ULONG Length,
\n__out PREPROTECT_CONTEXT ReprotectContext
\n)
\n{
\nNTSTATUS Status;<\/p>\n

Status = STATUS_SUCCESS;<\/p>\n

ReprotectContext->Mdl\u00a0\u00a0\u00a0\u00a0\u00a0 = 0;
\nReprotectContext->LockedVa = 0;<\/p>\n

ReprotectContext->Mdl = IoAllocateMdl(
\nVa,
\nLength,
\nFALSE,
\nFALSE,
\n0
\n);<\/p>\n

if (!ReprotectContext->Mdl)
\n{
\nreturn STATUS_INSUFFICIENT_RESOURCES;
\n}<\/p>\n

\/\/
\n\/\/ Retrieve a locked VA mapping.
\n\/\/<\/p>\n

__try
\n{
\nMmProbeAndLockPages(
\nReprotectContext->Mdl,
\nKernelMode,
\nIoModifyAccess
\n);
\n}
\n__except (EXCEPTION_EXECUTE_HANDLER)
\n{
\nreturn GetExceptionCode();
\n}<\/p>\n

ReprotectContext->LockedVa = (PUCHAR)MmMapLockedPagesSpecifyCache(
\nReprotectContext->Mdl,
\nKernelMode,
\nMmCached,
\n0,
\nFALSE,
\nNormalPagePriority
\n);<\/p>\n

if (!ReprotectContext->LockedVa)
\n{<\/p>\n

IoFreeMdl(
\nReprotectContext->Mdl
\n);<\/p>\n

ReprotectContext->Mdl = 0;<\/p>\n

return STATUS_ACCESS_VIOLATION;
\n}<\/p>\n

\/\/
\n\/\/ Reprotect.
\n\/\/<\/p>\n

Status = MmProtectMdlSystemAddress(
\nReprotectContext->Mdl,
\nPAGE_EXECUTE_READWRITE
\n);<\/p>\n

if (!NT_SUCCESS(Status))
\n{<\/p>\n

MmUnmapLockedPages(
\nReprotectContext->LockedVa,
\nReprotectContext->Mdl
\n);
\nMmUnlockPages(
\nReprotectContext->Mdl
\n);
\nIoFreeMdl(
\nReprotectContext->Mdl
\n);<\/p>\n

ReprotectContext->LockedVa = 0;
\nReprotectContext->Mdl\u00a0\u00a0\u00a0\u00a0\u00a0 = 0;
\n}<\/p>\n

return Status;
\n}<\/p>\n

NTSTATUS
\nMmUnlockVaForWrite(
\n__in PREPROTECT_CONTEXT ReprotectContext
\n)
\n{
\nif (ReprotectContext->LockedVa)
\n{
\nMmUnmapLockedPages(
\nReprotectContext->LockedVa,
\nReprotectContext->Mdl
\n);
\nMmUnlockPages(
\nReprotectContext->Mdl
\n);
\nIoFreeMdl(
\nReprotectContext->Mdl
\n);<\/p>\n

ReprotectContext->LockedVa = 0;
\nReprotectContext->Mdl\u00a0\u00a0\u00a0\u00a0\u00a0 = 0;
\n}<\/p>\n

return STATUS_SUCCESS;
\n}<\/p>\n","protected":false},"excerpt":{"rendered":"

\u6765\u6e90\uff1ahttp:\/\/hi.baidu.com\/%E5%8F%AB%E6%88%9 …<\/p>\n

\u7ee7\u7eed\u9605\u8bfb »<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[188],"class_list":["post-793","post","type-post","status-publish","format-standard","hentry","tag-mdl"],"views":935,"_links":{"self":[{"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/posts\/793","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/comments?post=793"}],"version-history":[{"count":0,"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/posts\/793\/revisions"}],"wp:attachment":[{"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/media?parent=793"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/categories?post=793"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/tags?post=793"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}