Change Details

Tests on the main 64-bit architectures prove that the ASLR is stable and does not result in noticable performance degradation. For 64-bit executables set honor_sbrk to 0. This allows ASLR to use bss grow region for mappings. Sbrk is currently deprecated and not widely used, so this setting should not have any significant impact on the OS memory footprint. On 32-bit architectures the implementation is however still unstable - please refer to attached analysis and https://reviews.freebsd.org/D27025. Contrary to other test-cases the issues were encountered when trying to perform buildworld. For the sake of safety keep ASLR is disabled for 32-bit executables on 64-bit machines, too.

Tests on the main 64-bit architectures prove that the ASLR is stable and does not result in noticeable performance degradation. By default use address map randomization for PIE binaries and disable SBRK, in order to allow to utilize the bss grow region for mappings. Both settings are respected only in case the ASLR is enabled. Although the tests on 32-bit architectures with ASLR enabled were mostly passed, the issues may be encountered for high memory consumption cases (e.g. buildworld). Therefore for the sake of safety keep ASLR is disabled for 32-bit executables on 64-bit machines, too.

Tests on the main 64-bit architectures prove that the ASLR is stable and does not result in noticeable performance degradation. For 64-bit executables set honor_sbrk to 0. This allows ASLR to useBy default use address map randomization for PIE binaries and disable SBRK, bss grow region for mappings. Sbrk is currently deprecated and notin order to allow to utilize the bss grow region for mappings. widely used, so thisBoth setting should not have any significant impact ons are respected only in case the OS memory footprintASLR is enabled. On 32-bit architectures the implementation is however still unstAlthough the tests on 32-bit architectures with ASLR enabled - please refer to attached analysis and https://reviews.freebsd.org/D27025.were mostly passed, the issues may be encountered Contrary to other test-cases the issues were encountered when trying to performfor high memory consumption cases (e.g. buildworld). ForTherefore for the sake of safety keep ASLR is disabled for 32-bit executables on 64-bit machines, too.