{"id":"CVE-2026-31770","summary":"hwmon: (occ) Fix division by zero in occ_show_power_1()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (occ) Fix division by zero in occ_show_power_1()\n\nIn occ_show_power_1() case 1, the accumulator is divided by\nupdate_tag without checking for zero. If no samples have been\ncollected yet (e.g. during early boot when the sensor block is\nincluded but hasn't been updated), update_tag is zero, causing\na kernel divide-by-zero crash.\n\nThe 2019 fix in commit 211186cae14d (\"hwmon: (occ) Fix division by\nzero issue\") only addressed occ_get_powr_avg() used by\nocc_show_power_2() and occ_show_power_a0(). This separate code\npath in occ_show_power_1() was missed.\n\nFix this by reusing the existing occ_get_powr_avg() helper, which\nalready handles the zero-sample case and uses mul_u64_u32_div()\nto multiply before dividing for better precision. Move the helper\nabove occ_show_power_1() so it is visible at the call site.\n\n[groeck: Fix alignment problems reported by checkpatch]","modified":"2026-05-18T05:59:54.391449694Z","published":"2026-05-01T14:14:59.256Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31770.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/243d55bd3f08cb15eee9d63f4716d4d4cdd760f5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2502684b9e835de9a992ec47c3e6c6faabe3858d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/37ae8fadc74ed68e5bc364ffd17746d88e449ae3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/39e2a5bf970402a8530a319cf06122e216ba57b8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/53e6175756b8c474b6247bbcea0aad3d68357475"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7b89ce0c98bf3015f493ca4285b2d1056cd8c733"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bbbefc48f6617cfb738dcff7f44beb50b5dfeb38"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c7d3712362c8ab8f82f441b649d9e446e7b9aa9d"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31770.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31770"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"c10e753d43ebd1d17e1c62bcee20c6124c2c7cca"},{"fixed":"c7d3712362c8ab8f82f441b649d9e446e7b9aa9d"},{"fixed":"53e6175756b8c474b6247bbcea0aad3d68357475"},{"fixed":"2502684b9e835de9a992ec47c3e6c6faabe3858d"},{"fixed":"37ae8fadc74ed68e5bc364ffd17746d88e449ae3"},{"fixed":"bbbefc48f6617cfb738dcff7f44beb50b5dfeb38"},{"fixed":"243d55bd3f08cb15eee9d63f4716d4d4cdd760f5"},{"fixed":"7b89ce0c98bf3015f493ca4285b2d1056cd8c733"},{"fixed":"39e2a5bf970402a8530a319cf06122e216ba57b8"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31770.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.0"},{"fixed":"5.10.253"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.203"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.168"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.134"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.81"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.22"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"6.19.12"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31770.json"}}],"schema_version":"1.7.5"}