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Unscored CVE-2026-98848 EUVD-2026-103788GHSA-hf5g-mj3f-66c7

rtc: ac100: Assign .num before accessing .hws

Published Oct 18, 2026 · Updated Oct 21, 2026 · Assigned by Linux

Vendor: Linux Product: Linux Package: kernel Package: linux Package: linux Package: linux-6.12 Package: linux-allwinner-5.19 Package: linux-aws Package: linux-aws-5.0 Package: linux-aws-5.11 Package: linux-aws-5.13 Package: linux-aws-5.19 Package: linux-aws-5.3 Package: linux-aws-5.8 Package: linux-aws-6.14 Package: linux-aws-6.17 Package: linux-aws-6.2 Package: linux-aws-6.5 Package: linux-aws-6.8 Package: linux-aws-7.0 Package: linux-aws-fips Package: linux-azure Package: linux-azure-5.11 Package: linux-azure-5.13 Package: linux-azure-5.19 Package: linux-azure-5.3 Package: linux-azure-5.8 Package: linux-azure-6.11 Package: linux-azure-6.14 Package: linux-azure-6.17 Package: linux-azure-6.2 Package: linux-azure-6.5 Package: linux-azure-6.8 Package: linux-azure-7.0 Package: linux-azure-edge Package: linux-azure-fde Package: linux-azure-fde-5.19 Package: linux-azure-fde-6.14 Package: linux-azure-fde-6.17 Package: linux-azure-fde-6.2 Package: linux-azure-fde-6.8 Package: linux-azure-fde-7.0 Package: linux-azure-fips Package: linux-azure-nvidia Package: linux-azure-nvidia-6.14 Package: linux-bluefield Package: linux-fips Package: linux-gcp Package: linux-gcp-5.11 Package: linux-gcp-5.13 Package: linux-gcp-5.19 Package: linux-gcp-5.3 Package: linux-gcp-5.8 Package: linux-gcp-6.11 Package: linux-gcp-6.14 Package: linux-gcp-6.17 Package: linux-gcp-6.2 Package: linux-gcp-6.5 Package: linux-gcp-6.8 Package: linux-gcp-7.0 Package: linux-gcp-fips Package: linux-gke Package: linux-gke-4.15 Package: linux-gke-5.15 Package: linux-gke-5.4 Package: linux-gkeop Package: linux-gkeop-5.15 Package: linux-gkeop-5.4 Package: linux-hwe Package: linux-hwe-5.11 Package: linux-hwe-5.13 Package: linux-hwe-5.19 Package: linux-hwe-5.8 Package: linux-hwe-6.11 Package: linux-hwe-6.14 Package: linux-hwe-6.17 Package: linux-hwe-6.2 Package: linux-hwe-6.5 Package: linux-hwe-6.8 Package: linux-hwe-7.0 Package: linux-hwe-edge Package: linux-ibm Package: linux-ibm-6.8 Package: linux-intel-5.13 Package: linux-intel-iot-realtime Package: linux-lowlatency Package: linux-lowlatency-hwe-5.19 Package: linux-lowlatency-hwe-6.11 Package: linux-lowlatency-hwe-6.2 Package: linux-lowlatency-hwe-6.5 Package: linux-lowlatency-hwe-6.8 Package: linux-nvidia Package: linux-nvidia-6.11 Package: linux-nvidia-6.17 Package: linux-nvidia-6.2 Package: linux-nvidia-6.5 Package: linux-nvidia-6.8 Package: linux-nvidia-7.0 Package: linux-nvidia-bos Package: linux-nvidia-lowlatency Package: linux-nvidia-tegra Package: linux-oem Package: linux-oem-5.10 Package: linux-oem-5.13 Package: linux-oem-5.14 Package: linux-oem-5.17 Package: linux-oem-5.6 Package: linux-oem-6.0 Package: linux-oem-6.1 Package: linux-oem-6.11 Package: linux-oem-6.14 Package: linux-oem-6.17 Package: linux-oem-6.5 Package: linux-oem-6.8 Package: linux-oem-7.0 Package: linux-oracle Package: linux-oracle-5.0 Package: linux-oracle-5.11 Package: linux-oracle-5.13 Package: linux-oracle-5.3 Package: linux-oracle-5.8 Package: linux-oracle-6.14 Package: linux-oracle-6.17 Package: linux-oracle-6.5 Package: linux-oracle-6.8 Package: linux-oracle-7.0 Package: linux-raspi Package: linux-raspi-realtime Package: linux-raspi2 Package: linux-realtime Package: linux-realtime-6.14 Package: linux-realtime-6.17 Package: linux-realtime-6.8 Package: linux-riscv Package: linux-riscv-5.11 Package: linux-riscv-5.19 Package: linux-riscv-5.8 Package: linux-riscv-6.14 Package: linux-riscv-6.17 Package: linux-riscv-6.5 Package: linux-riscv-6.8 Package: linux-riscv-7.0 Package: linux-starfive-5.19 Package: linux-starfive-6.2 Package: linux-starfive-6.5 Package: linux-vmware Package: linux-xilinx Platform: Linux Ecosystem: Azure Linux Ecosystem: Debian Ecosystem: Ubuntu

Description

In the Linux kernel, the following vulnerability has been resolved:

rtc: ac100: Assign .num before accessing .hws

Commit f316cdff8d67 ("clk: Annotate struct clk_hw_onecell_data with
__counted_by") annotated the hws member of 'struct clk_hw_onecell_data'
with __counted_by, which informs the bounds sanitizer (UBSAN_BOUNDS)
about the number of elements in .hws[], so that it can warn when .hws[]
is accessed out of bounds. As noted in that change, the __counted_by
member must be initialized with the number of elements before the first
array access happens, otherwise there will be a warning from each access
prior to the initialization because the number of elements is zero.
This occurs in ac100_rtc_register_clks() due to .num being assigned only
after every clkout clock has been stored in .hws[]. With
CONFIG_UBSAN_BOUNDS and a compiler that implements __counted_by (GCC
15.1+ or Clang 20.1+), this triggers an array-index-out-of-bounds report
during probe, and with CONFIG_UBSAN_TRAP the first store traps.

Initialize .num with AC100_CLKOUT_NUM, the number of elements .hws[] was
allocated with, right after the allocation. That is the value the loop
counter ends up at on the success path anyway, so the provider's
behaviour is unchanged.

Affected products

VendorProductAffectedFixed
Linux Linux 6.6 6.6.160

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Debian 14 linux 7.2.10-1 —
Debian 13 linux 6.12.113-1 —
Debian 12 linux-6.12 6.12.113-1~deb12u1 —
ReleasePackageFixed inAdvisory
Ubuntu Nvidia-BlueField 24.04 LTS linux-bluefield 6.8.0-1036.41 —
Ubuntu 26.04 LTS linux 7.0.0-43.43 USN-9018-1
Ubuntu 26.04 LTS linux-aws 7.0.0-1017.18 USN-9018-1
Ubuntu 26.04 LTS linux-azure 7.0.0-1020.21 USN-9019-1
Ubuntu 26.04 LTS linux-azure-fde 7.0.0-1019.19 USN-9020-1
Ubuntu 26.04 LTS linux-gcp 7.0.0-1017.19 USN-9018-1
Ubuntu 26.04 LTS linux-gke 7.0.0-1010.11 USN-9020-1
Ubuntu 26.04 LTS linux-ibm +1 7.0.0-1018.18 USN-9018-1
Ubuntu 26.04 LTS linux-oracle 7.0.0-1016.18 USN-9018-1
Ubuntu 26.04 LTS linux-raspi 7.0.0-1023.23 USN-9021-1
Ubuntu 26.04 LTS linux-realtime 7.0.0-43.43.1 USN-9020-1
Ubuntu 26.04 LTS linux-riscv +2 No fix yet —
Ubuntu 24.04 LTS linux 6.8.0-149.149 USN-9022-1
Ubuntu 24.04 LTS linux-aws 6.8.0-1069.74 USN-9022-1
Ubuntu 24.04 LTS linux-aws-7.0 7.0.0-1017.18~24.04.1 USN-9020-1
Ubuntu 24.04 LTS linux-azure 6.8.0-1073.82 USN-9022-1
Ubuntu 24.04 LTS linux-azure-fde 6.8.0-1071.78 USN-9039-1
Ubuntu 24.04 LTS linux-azure-fde-7.0 7.0.0-1019.19~24.04.1 USN-9020-1
Ubuntu 24.04 LTS linux-gcp 6.8.0-1073.81 USN-9022-1
Ubuntu 24.04 LTS linux-gcp-7.0 7.0.0-1017.19~24.04.1 USN-9020-1
Ubuntu 24.04 LTS linux-gke 6.8.0-1068.77 USN-9022-1
Ubuntu 24.04 LTS linux-gkeop 6.8.0-1053.57 USN-9023-1
Ubuntu 24.04 LTS linux-hwe-7.0 7.0.0-43.43~24.04.1 USN-9018-2
Ubuntu 24.04 LTS linux-ibm 6.8.0-1069.70 USN-9022-1
Ubuntu 24.04 LTS linux-lowlatency 6.8.0-149.149.1 USN-9022-1
Ubuntu 24.04 LTS linux-nvidia 6.8.0-1067.70 USN-9024-1
Ubuntu 24.04 LTS linux-nvidia-lowlatency 6.8.0-1067.70.1 USN-9040-1
Ubuntu 24.04 LTS linux-nvidia-tegra 6.8.0-1039.40 USN-9091-1
Ubuntu 24.04 LTS linux-oracle 6.8.0-1067.71 USN-9022-1
Ubuntu 24.04 LTS linux-oracle-7.0 7.0.0-1016.18~24.04.1 USN-9020-1
Ubuntu 24.04 LTS linux-raspi 6.8.0-1068.72 USN-9025-1
Ubuntu 24.04 LTS linux-riscv +31 No fix yet —
Ubuntu 24.04 LTS linux-riscv-7.0 7.0.0-43.43.1~24.04.2 —
Ubuntu 24.04 LTS linux-vmware 6.8.0-1010.10 USN-9022-1
Ubuntu 22.04 LTS linux-aws-6.8 6.8.0-1069.74~22.04.1 USN-9024-1
Ubuntu 22.04 LTS linux-azure-6.8 6.8.0-1073.82~22.04.1 USN-9026-1
Ubuntu 22.04 LTS linux-azure-fde-6.8 6.8.0-1071.78~22.04.1 USN-9026-1
Ubuntu 22.04 LTS linux-gcp-6.8 6.8.0-1073.81~22.04.1 USN-9024-1
Ubuntu 22.04 LTS linux-hwe-6.8 6.8.0-149.149~22.04.1 USN-9066-1
Ubuntu 22.04 LTS linux-ibm-6.8 6.8.0-1069.70~22.04.1 USN-9024-1
Ubuntu 22.04 LTS linux-lowlatency-hwe-6.8 6.8.0-149.149.1~22.04.1 USN-9024-1
Ubuntu 22.04 LTS linux-oracle-6.8 6.8.0-1067.71~22.04.1 USN-9025-1
Ubuntu 22.04 LTS linux-riscv +33 No fix yet —
Ubuntu 22.04 LTS linux-riscv-6.8 6.8.0-149.149~22.04.2 —
Ubuntu 20.04 LTS linux-gke +28 No fix yet —
Show 5 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Ubuntu 18.04 LTS linux-gcp +14 No fix yet —
Ubuntu 16.04 LTS linux-hwe-edge No fix yet —
Ubuntu Pro Realtime 24.04 LTS linux-raspi-realtime 6.8.0-2056.58 USN-9025-1
Ubuntu Pro Realtime 24.04 LTS linux-realtime 6.8.1-1064.65 USN-9023-1
Ubuntu Pro Realtime 24.04 LTS linux-realtime-6.14 +1 No fix yet —
Ubuntu Pro Realtime 22.04 LTS linux-realtime-6.8 6.8.1-1064.65~22.04.1 USN-9024-1
Ubuntu Pro FIPS-updates 24.04 LTS linux-aws-fips 6.8.0-1069.74+fips1 USN-9023-1
Ubuntu Pro FIPS-updates 24.04 LTS linux-azure-fips 6.8.0-1073.82+fips1 USN-9022-1
Ubuntu Pro FIPS-updates 24.04 LTS linux-fips No fix yet —
Ubuntu Pro FIPS-updates 24.04 LTS linux-gcp-fips 6.8.0-1073.81+fips1 USN-9023-1
ReleasePackageFixed inAdvisory
SLES 15 SP7 kernel-64kb +7 6.4.0-150700.53.90.1 SUSE-SU-2026:5091-1
SLES 15 SP7 kernel-default-base 6.4.0-150700.53.90.1.150700.17.51.1 SUSE-SU-2026:5091-1
Show 6 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
SLES for SAP 16.0 kernel-64kb +8 6.12.0-160000.41.1 SUSE-SU-2026:24662-1
SLES for SAP 16.0 kernel-default-base 6.12.0-160000.41.1.160000.2.32 SUSE-SU-2026:24662-1
SLES 16.0 kernel-64kb +8 6.12.0-160000.41.1 SUSE-SU-2026:24662-1, SUSE-SU-2026:24651-1
SLES 16.0 kernel-default-base 6.12.0-160000.41.1.160000.2.32 SUSE-SU-2026:24662-1
SLE Micro 6.2 kernel-default-base 6.12.0-160000.41.1.160000.2.32 SUSE-SU-2026:24643-1
SLE Micro 6.2 kernel-rt +5 6.12.0-160000.41.1 SUSE-SU-2026:24648-1, SUSE-SU-2026:24643-1
SLE Micro 6.1 kernel-default-base 6.4.0-159998.55.1.159998.21.41 SUSE-SU-2026:24619-1
SLE Micro 6.1 kernel-source +2 6.4.0-159998.55.1 SUSE-SU-2026:24619-1
SLE Micro 6.0 kernel-default-base 6.4.0-159998.55.1.159998.21.42 SUSE-SU-2026:24550-1
SLE Micro 6.0 kernel-source +2 6.4.0-159998.55.1 SUSE-SU-2026:24550-1
SLE Live Patching 15 SP7 kernel-default 6.4.0-150700.53.90.1 SUSE-SU-2026:5091-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7_Update_24 1-150700.15.3.1 SUSE-SU-2026:5091-1

Azure Linux

ReleasePackageFixed inAdvisory
Azure Linux 3 kernel 6.6.161.1-1 —

Advisories 22

References