make Android use mmap to make write+exec mappings#240
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notaz wants to merge 2 commits intolibffi:masterfrom
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make Android use mmap to make write+exec mappings#240notaz wants to merge 2 commits intolibffi:masterfrom
notaz wants to merge 2 commits intolibffi:masterfrom
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Some Android versions use SELinux, but it doesn't seem to complain about write+exec mappings. Also the check depends on getline(), which older versions of NDK lack.
On Linux, by default libffi relies on malloc() memory to have write+execute permissions, which is usually comes as a side effect of making the stack executable (either by execstack linker option or by compiling and linking some .S files; libffi linked programs get linked to such objects). On Android, at least on some versions of NDK for ARM, it is not enough to just link some objects compiled from .S (or libffi) to enable execstack and to get executable heap, so libffi just crashes in such configuration. It can be argued it's not even desirable to make the whole heap executable because of security implications, so enable FFI_MMAP_EXEC_WRIT to make only needed memory executable instead.
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Could you rebase this PR to master? Conflicts arise since commit 30b3440.
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#265 created |
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This is already used by java-native-access/jna , for example