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> The problem is that a PAX_FLAGS program header is not |
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> standard while user defined xattrs are. eg. EI_PAX used to put the |
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> markers in the ELF header (in a non-standard way) until that got |
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> clobbered by a commit in glibc; similarly pax markings in the program |
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> header cause issue in cases like the above. XT_PAX has the advantage |
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> of not violating a standard while the disadvantage of needing |
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> end-to-end xattr support. |
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I think the issue here is not, that a non-standard way is used. It is, |
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that the best way to use PAX markings is not standardized. It should be |
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added to the ELF standard (in a generalized way, so that other runtime |
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exploit mitigation suites could use that standard too). |
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I do not know, whether there are valid use cases for using PAX-marked |
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binaries on non-xattr-capable file systems. It just feels like that |
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markings belong more to the binary itself than to the reference to that |
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binary in the file system. |
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> I have no intentions of dropping PT_PAX anytime soon. toolchain did |
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> indicate a desire to do so because the program header causes issues in |
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> binutils' test suite, but dropping PT_AX is a long range plan if it |
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> will ever happen. |
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I am relieved to read that. So i do not have to rebuild the kernels yet |
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(i may have configured Grsec to only use the markings in the ELF header |
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- but i am not sure about that). |
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> The current issue, in my opinion, is how to spead up the install |
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> wrapper which is written in python and slow as hell. |
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Has the bottleneck already been identified? Python should not be much |
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slower than other languages for solving mostly IO-based problems. |
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-- |
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Allan Wegan |
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Jabber: allanwegan@×××××.de |
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ICQ: 209459114 |
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