SUSE: CVE-2024-26670: SUSE Linux Security Advisory
Description
In the Linux kernel, the following vulnerability has been resolved: arm64: entry: fix ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD Currently the ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD workaround isn't quite right, as it is supposed to be applied after the last explicit memory access, but is immediately followed by an LDR. The ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD workaround is used to handle Cortex-A520 erratum 2966298 and Cortex-A510 erratum 3117295, which are described in: * https://developer.arm.com/documentation/SDEN2444153/0600/?lang=en * https://developer.arm.com/documentation/SDEN1873361/1600/?lang=en In both cases the workaround is described as: | If pagetable isolation is disabled, the context switch logic in the | kernel can be updated to execute the following sequence on affected | cores before exiting to EL0, and after all explicit memory accesses: | | 1. A non-shareable TLBI to any context and/or address, including | unused contexts or addresses, such as a `TLBI VALE1 Xzr`. | | 2. A DSB NSH to guarantee completion of the TLBI. The important part being that the TLBI+DSB must be placed "after all explicit memory accesses". Unfortunately, as-implemented, the TLBI+DSB is immediately followed by an LDR, as we have: | alternative_if ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD | tlbi vale1, xzr | dsb nsh | alternative_else_nop_endif | alternative_if_not ARM64_UNMAP_KERNEL_AT_EL0 | ldr lr, [sp, #S_LR] | add sp, sp, #PT_REGS_SIZE // restore sp | eret | alternative_else_nop_endif | | [ ... KPTI exception return path ... ] This patch fixes this by reworking the logic to place the TLBI+DSB immediately before the ERET, after all explicit memory accesses. The ERET is currently in a separate alternative block, and alternatives cannot be nested. To account for this, the alternative block for ARM64_UNMAP_KERNEL_AT_EL0 is replaced with a single alternative branch to skip the KPTI logic, with the new shape of the logic being: | alternative_insn "b .L_skip_tramp_exit_\@", nop, ARM64_UNMAP_KERNEL_AT_EL0 | [ ... KPTI exception return path ... ] | .L_skip_tramp_exit_\@: | | ldr lr, [sp, #S_LR] | add sp, sp, #PT_REGS_SIZE // restore sp | | alternative_if ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD | tlbi vale1, xzr | dsb nsh | alternative_else_nop_endif | eret The new structure means that the workaround is only applied when KPTI is not in use; this is fine as noted in the documented implications of the erratum: | Pagetable isolation between EL0 and higher level ELs prevents the | issue from occurring. ... and as per the workaround description quoted above, the workaround is only necessary "If pagetable isolation is disabled".
Solution(s)
- suse-upgrade-cluster-md-kmp-64kb
- suse-upgrade-cluster-md-kmp-azure
- suse-upgrade-cluster-md-kmp-default
- suse-upgrade-cluster-md-kmp-rt
- suse-upgrade-dlm-kmp-64kb
- suse-upgrade-dlm-kmp-azure
- suse-upgrade-dlm-kmp-default
- suse-upgrade-dlm-kmp-rt
- suse-upgrade-dtb-allwinner
- suse-upgrade-dtb-altera
- suse-upgrade-dtb-amazon
- suse-upgrade-dtb-amd
- suse-upgrade-dtb-amlogic
- suse-upgrade-dtb-apm
- suse-upgrade-dtb-apple
- suse-upgrade-dtb-arm
- suse-upgrade-dtb-broadcom
- suse-upgrade-dtb-cavium
- suse-upgrade-dtb-exynos
- suse-upgrade-dtb-freescale
- suse-upgrade-dtb-hisilicon
- suse-upgrade-dtb-lg
- suse-upgrade-dtb-marvell
- suse-upgrade-dtb-mediatek
- suse-upgrade-dtb-nvidia
- suse-upgrade-dtb-qcom
- suse-upgrade-dtb-renesas
- suse-upgrade-dtb-rockchip
- suse-upgrade-dtb-socionext
- suse-upgrade-dtb-sprd
- suse-upgrade-dtb-xilinx
- suse-upgrade-gfs2-kmp-64kb
- suse-upgrade-gfs2-kmp-azure
- suse-upgrade-gfs2-kmp-default
- suse-upgrade-gfs2-kmp-rt
- suse-upgrade-kernel-64kb
- suse-upgrade-kernel-64kb-devel
- suse-upgrade-kernel-64kb-extra
- suse-upgrade-kernel-64kb-livepatch-devel
- suse-upgrade-kernel-64kb-optional
- suse-upgrade-kernel-azure
- suse-upgrade-kernel-azure-devel
- suse-upgrade-kernel-azure-extra
- suse-upgrade-kernel-azure-livepatch-devel
- suse-upgrade-kernel-azure-optional
- suse-upgrade-kernel-azure-vdso
- suse-upgrade-kernel-debug
- suse-upgrade-kernel-debug-devel
- suse-upgrade-kernel-debug-livepatch-devel
- suse-upgrade-kernel-debug-vdso
- suse-upgrade-kernel-default
- suse-upgrade-kernel-default-base
- suse-upgrade-kernel-default-base-rebuild
- suse-upgrade-kernel-default-devel
- suse-upgrade-kernel-default-extra
- suse-upgrade-kernel-default-livepatch
- suse-upgrade-kernel-default-livepatch-devel
- suse-upgrade-kernel-default-optional
- suse-upgrade-kernel-default-vdso
- suse-upgrade-kernel-devel
- suse-upgrade-kernel-devel-azure
- suse-upgrade-kernel-devel-rt
- suse-upgrade-kernel-docs
- suse-upgrade-kernel-docs-html
- suse-upgrade-kernel-kvmsmall
- suse-upgrade-kernel-kvmsmall-devel
- suse-upgrade-kernel-kvmsmall-livepatch-devel
- suse-upgrade-kernel-kvmsmall-vdso
- suse-upgrade-kernel-macros
- suse-upgrade-kernel-obs-build
- suse-upgrade-kernel-obs-qa
- suse-upgrade-kernel-rt
- suse-upgrade-kernel-rt-devel
- suse-upgrade-kernel-rt-extra
- suse-upgrade-kernel-rt-livepatch
- suse-upgrade-kernel-rt-livepatch-devel
- suse-upgrade-kernel-rt-optional
- suse-upgrade-kernel-rt-vdso
- suse-upgrade-kernel-rt_debug
- suse-upgrade-kernel-rt_debug-devel
- suse-upgrade-kernel-rt_debug-livepatch-devel
- suse-upgrade-kernel-rt_debug-vdso
- suse-upgrade-kernel-source
- suse-upgrade-kernel-source-azure
- suse-upgrade-kernel-source-rt
- suse-upgrade-kernel-source-vanilla
- suse-upgrade-kernel-syms
- suse-upgrade-kernel-syms-azure
- suse-upgrade-kernel-syms-rt
- suse-upgrade-kernel-zfcpdump
- suse-upgrade-kselftests-kmp-64kb
- suse-upgrade-kselftests-kmp-azure
- suse-upgrade-kselftests-kmp-default
- suse-upgrade-kselftests-kmp-rt
- suse-upgrade-ocfs2-kmp-64kb
- suse-upgrade-ocfs2-kmp-azure
- suse-upgrade-ocfs2-kmp-default
- suse-upgrade-ocfs2-kmp-rt
- suse-upgrade-reiserfs-kmp-64kb
- suse-upgrade-reiserfs-kmp-azure
- suse-upgrade-reiserfs-kmp-default
- suse-upgrade-reiserfs-kmp-rt
- Lightweight Endpoint Agent
- Live Dashboards
- Real Risk Prioritization
- IT-Integrated Remediation Projects
- Cloud, Virtual, and Container Assessment
- Integrated Threat Feeds
- Easy-to-Use RESTful API
- Automation-Assisted Patching
- Automated Containment
With Rapid7 live dashboards, I have a clear view of all the assets on my network, which ones can be exploited, and what I need to do in order to reduce the risk in my environment in real-time. No other tool gives us that kind of value and insight.
– Scott Cheney, Manager of Information Security, Sierra View Medical Center