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On Thu, 15 Jun 2017 19:52:07 -0500 Matthias Maier wrote: |
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> > there should be a way of turning these off systematically. the |
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> > advantage of the current hardened gcc specs is that one can switch |
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> > between them using gcc-config. if these are forced on for the default |
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> > profile then there will be no easy way to systematically turn them off. |
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> |
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> No - there won't be an easy way for systematically turning off |
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> SSP and PIE in 17.0 profiles [1,2]. |
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> |
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> The hardened toolchain with its different gcc profiles came from a time |
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> where SSP and PIE were relatively new security features and a certain |
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> amount of fine-grained control was needed. Further, at that time we were |
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> talking about external patches against gcc. Nowadays everything is |
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> upstreamed and (almost) no patches to gcc for hardened profiles are |
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> applied any more. |
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> |
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> Given the fact that all major linux distributions are following the path |
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> of improved default hardening features (see for example [1]) and that we |
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> have been using ssp/pie in hardened profiles for years now the purpose |
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> of fine-grained control over ssp/pie is also highly questionable. |
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> |
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> The consensus at the moment is that PIE and SSP (as well as stricter |
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> linker flags) will soon be standard (or, actually *are* already |
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> standard) compilation options. A per-package override (if absoluetely |
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> needed) is fine - and, in fact, already in place everywhere where |
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> needed. |
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Gentoo is all about choice, remember? :) |
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It is really good to have them by default, it is bad to force them |
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on everyone. Security is not always of paramount importance |
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comparing to other factors, sometimes performance matters more, |
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e.g. in isolated and restricted non-public HPC environment. |
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PIE, SSP may lead up to 8% of performance loss[1]. The |
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stack-protector (especially stack-protector-all or -strong) may |
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cause even more damage. For compute nodes this may be equivalent to |
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millions USD loss (depends on the system scale of course). |
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[1] https://bugs.archlinux.org/task/18864 |
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Best regards, |
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Andrew Savchenko |
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