SRU stands for "Stable Release Update" and describes the process that is needed to get a patch (or patches) to fix critical issues into components that are part of an Ubuntu version that is already released (post GA).
The process for packages (https://wiki.ubuntu.com/StableReleaseUpdates) is slightly different compared to the SRU process for the kernel: https://wiki.ubuntu.com/KernelTeam/KernelUpdates But there is also such a 'stable release update' process in use upstream at kernel.org. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1877955 Title: Fix for secure boot rules in IMA arch policy on powerpc Status in The Ubuntu-power-systems project: Triaged Status in linux package in Ubuntu: Triaged Bug description: SRU Justification: ================== [Impact] * Currently the kernel module appended signature is verified twice (finit_module) - once by the module_sig_check() and again by IMA. * To prevent this the powerpc secure boot rules define an IMA architecture specific policy rule only if CONFIG_MODULE_SIG_FORCE is not enabled. * But this doesn't take the ability into account of enabling "sig_enforce" at the boot command line (module.sig_enforce=1). * Including the IMA module appraise rule results in failing the finit_module syscall, unless the module signing public key is loaded onto the IMA keyring. * This patch fixes secure boot policy rules to be based on CONFIG_MODULE_SIG instead. [Fix] * fa4f3f56ccd28ac031ab275e673ed4098855fed4 fa4f3f56ccd2 "powerpc/ima: Fix secure boot rules in ima arch policy" [Test Case] * Perform a secure boot on a powerpc system with 'module.sig_enforce=1' set at the boot command. * If the IMA module appraise rule is included, the finit_module syscall will fail (unless the module signing public key got loaded onto the IMA keyring) without having the patch in place. * The verification needs to be done by the IBM Power team. [Regression Potential] * There is (always) a certain regression risk with having code changes, especially in the secure boot area. * But this patch is limited to the powerpc platform and will not affect any other architecture. * It got discussed at https://lore.kernel.org/r/1588342612-14532-1-git-send-email-na...@linux.ibm.com before it became finally upstream accepted with kernel 5.7-rc7. * The secure boot code itself wasn't really touched, rather than it's basis for execution. The IMA policy rule for module appraisal is now added only if 'CONFIG_MODULE_SIG' is not enabled (instead of CONFIG_MODULE_SIG_FORCE). Hence the change is very limited and straightforward. [Other] * Since the patch got upstream with 5.7-rc7, it is already in groovy, hence this SRU is for focal only. __________ == Comment: #0 - Michael Ranweiler <mranw...@us.ibm.com> - 2020-04-22 14:44:31 == +++ This bug was initially created as a clone of Bug #184073 +++ This bug is a follow on to LP 1866909 to address a missing piece - only half the following patch was included in 5.4.0-24.28. The upstream patch has an additional fix but it?s not critical for GA. It can get included as part of bug fixes. It also affects only power. The patch("powerpc/ima: fix secure boot rules in ima arch policy") is posted to linux-integrity and linuxppc-dev mailing list (https://lore.kernel.org/linux-integrity/1586549618-6106-1-git-send- email-na...@linux.ibm.com/T/#u) If there are any issues identified during further testing, they will get opened as separate issue to be addressed later. Thanks & Regards, - Nayna == Comment: #4 - Michael Ranweiler <mranw...@us.ibm.com> - 2020-05-11 02:23:35 == Updated posting: https://lore.kernel.org/linux-integrity/1588342612-14532-1-git-send- email-na...@linux.ibm.com/T/#u To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1877955/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
