如何使 .NET 应用程序“识别大地址”？

Question

假设我已经使用 /3GB 开关启动了一个 32 位 Windows 服务器，我怎样才能让 .NET 应用程序使用额外的地址空间？

Answer 1

The flag is part of the image header, so you need to modify that using editbin.

editbin /LARGEADDRESSAWARE <your exe>

Use dumpbin /headers and look for the presence of Application can handle large (>2GB) addresses to see if the flag is set or not.

Answer 2

From what I can tell you have to use the editbin utility shown in the existing answer. There does not appear to be any way to set the flag using Visual Studio .NET, it looks like they encourage people to compile for 64 bit if possible instead of using the flag

http://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=93771

Answer 3

要从 Visual Studio 自动执行此操作，请参阅此问题：来自 Visual Studio 的标志。

Answer 4

Add those lines to Post build:

call "$(DevEnvDir)..\tools\vsdevcmd.bat"
editbin /largeaddressaware "$(TargetPath)"

From: vsvars32.bat in Visual Studio 2017

Answer 5

Thus far there haven't been an answer giving a cross-platform and open-source way to set LAA bit on a PE executable, so I decided to fill the gap.

Note: make sure you have a backup!

You can that with reverse-engineering framework radare2. In case you use a Linux distro, radare2 is typically in the repository. Unfortunately, the capability to set the bit isn't built-in, nonetheless it is quite easy with the following script:

e cfg.newshell=true      # allows nested $(…) commands
s/ PE\0\0                # search PE file signature
s +4                     # skip the signature
echo "Original content:"
pf.pe_image_file_header.characteristics
echo "Patching the file…"
s+ 0x12                  # go to the characteristics field
wv2 $(?v $(pv2) \| 0x20) # 0x20 is the LAA bit, binary-OR it in the address
s-
echo "The new content:"
pf.pe_image_file_header.characteristics

Here's a demo how you use it (the script is in script.r2 file) with a notepad.exe file:

 λ r2 -qi script.r2 -nnw notepad.exe
Searching 4 bytes in [0x1-0x620ca]
0x00000080 hit0_0 .mode.$PE\u0000\u0000Ld`J.
Original content:
      characteristics : 0x00000096 = characteristics (bitfield) = 0x00000107 : IMAGE_FILE_RELOCS_STRIPPED | IMAGE_FILE_EXECUTABLE_IMAGE | IMAGE_FILE_LINE_NUMS_STRIPPED | IMAGE_FILE_32BIT_MACHINE
Patching the file…
The new content:
      characteristics : 0x00000096 = characteristics (bitfield) = 0x00000127 : IMAGE_FILE_RELOCS_STRIPPED | IMAGE_FILE_EXECUTABLE_IMAGE | IMAGE_FILE_LINE_NUMS_STRIPPED | IMAGE_FILE_LARGE_ADDRESS_AWARE | IMAGE_FILE_32BIT_MACHINE

To double check it worked you can also use use objdump -p notepad.exe | grep "large address aware" objdump -p notepad.exe | grep "large address aware" command and see that it has output.