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On 25 March 2013 07:01, Kfir Lavi <lavi.kfir@×××××.com> wrote: |
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> Hi, |
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> I'm looking for a way to reduce glibc code size. |
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> It can be a way to make system smaller and minimize the impact |
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> of attack vectors in glibc, as in return-to-libc attack. |
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> |
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> Lets say I'm deleting the program 'mkdir', and mkdir uses a function |
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> in glibc that non of the other parts of the system uses. |
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> Then I want to eliminate this function from glibc. This leads to smaller |
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> code and if this function is used in some attack scenario, maybe prevent it. |
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> |
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> Is there a way to do it? |
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> Can you help me think how to build a tool like this? or, integrate |
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> with existing tools. |
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> |
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> Thanks, |
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> Kfir |
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> |
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|
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You can use -Os when you compile your packages to reduce the size of |
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the resulting ELF file. |
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As for the second part of your question, I am not sure if this is |
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possible. I haven't thought this through, but |
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assuming you know no other packages depend on the function you want to |
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remove, you will have to mess |
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with the ELF file and its plt and other section entries to remove all |
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the references of that symbol. It's likely you |
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will break the file in the end. |
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|
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-- |
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Regards, |
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Markos Chandras - Gentoo Linux Developer |
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http://dev.gentoo.org/~hwoarang |
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