Tony0945 wrote:Three months ago! How ancient! How old is the kernel that some Ubuntu user installed last year? I for one am rather sick of the "kernel of the week" obviously inadequately tested kernels coming out of kernel.org lately. Kernels used to be updated every six months to a year and 2.2 lasted quite a while alongside the radically different 2.4 The present kernels should be marked as "release candidates" by upstream rather than as "stable".
As a general rule, the upstream maintainers refuse to differentiate bug fixes from security fixes, and instead categorize all fixes as "must upgrade" fixes. This leads to the problem that if you want any security fixes, you need to pull everything marked as a fix of any sort because it
might be a security fix (unless you want to spend substantial programmer effort determining it is not a security fix, and you get to do this for each of the dozens of patches in each stable kernel). Combine this with the frequent difficulty of determining whether a fix (whether security or other) impacts code you use and it becomes difficult to identify kernels you can skip if you want all applicable security fixes. (You might get lucky and the fix only affects people who use some feature that you compiled out, hence applying the patch to your kernel has no impact on the generated code because you never built the bad code in the first place.) The threat model for these updates is that malicious actors can rapidly weaponize any vulnerability, and will become aware of the vulnerability $soon, where $soon ranges from "when the bug (not the fix!) was first added" to "within a few days of the fix being posted," depending on how lucky you are. If your threat model is less severe (e.g. "all my local users run only trusted code"), you can probably skip some classes of security fix - but good luck figuring out whether all the fixes in a given release fit within that more relaxed threat model, since first you need to find which fixes are even security relevant and applicable to your system, then filter those for whether you expect someone might try to exploit them.
I'd love to see some tooling that could at least address the question "Given this patch, and my kernel configuration, will applying this patch and rebuilding result in a kernel that is functionally different than the unpatched kernel?" That omits the harder steps relating to finding important patches, but is a useful first filter. If the patch doesn't change the compiled code, it can't possibly be security relevant to that configuration.
Tony0945 wrote:NeddySeagoon wrote:It seems its Gentoos
gcc
Thanks for the link. Apparently it only affects Intel cpu's because I had these kernels running on two k10's and a Kaveri with no problem.
Can't this be implemented as an "r" revision with a patch to the ebuild rather than masking the whole kernel?
Code: Select all
KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
Probably it could. I think the mask was put in before anyone knew what caused the problem, so it was an emergency mask to prevent users breaking their kernels while debugging was done.