{"id":"CVE-2026-74643","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nsamples/damon/mtier: error out for zero quota goal target values\n\nPatch series \"mm/damon: avoid division by zero from damos_quota_score()\".\n\nDAMON_SAMPLE_MTIER and DAMO…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nsamples/damon/mtier: error out for zero quota goal target values\n\nPatch series \"mm/damon: avoid division by zero from damos_quota_score()\".\n\nDAMON_SAMPLE_MTIER and DAMO…","severity":"none","published":"2026-08-22","updated":"2026-10-14","sourceUpdated":"2026-10-14T13:10:00.187","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74643","references":[{"url":"https://git.kernel.org/stable/c/684f271210becd7b8c4088f06c442499e48a43a0","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a16fd3ad9d89b05475864da97327870464611736","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e16b8d640ec99b28bc827560edcf9706e610c3aa","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00206,"epssPercentile":0.09945,"ingestedAt":"2026-10-14T13:30:58.524Z","slug":"CVE-2026-74643","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nsamples/damon/mtier: error out for zero quota goal target values\n\nPatch series \"mm/damon: avoid division by zero from damos_quota_score()\".\n\nDAMON_SAMPLE_MTIER and DAMON_LRU_SORT allow the user to trigger division\nby zero in damos_quota_score().  Avoid it by adding parameters validation\nchecks.\n\n\nThis patch (of 2):\n\ndamos_quota_score() can trigger division by zero if the target_value is\nzero.  DAMON_SAMPLE_MTIER lets users set the target_value via\nnode0_mem_{used,free}_bp parameters.  It doesn't guard zero value case,\nthough.  As a result, users can trigger division by zero.  Fix the issue\nby returning an error when the user tries to start DAMON with zero\nnode0_mem_{used,free}_bp parameter values.\n\nDAMON_SAMPLE_MTIER is just a sample module, but the consequence is quite\nbad.  Also the zero node0_mem_free_bp parameter might look like a\nreasonable setup to some users.  Hence, the issue might really happen in\nthe real world.\n\nOne reliable way to reproduce the issue is like below:\n\n    # cd /sys/module/damon_sample_mtier/parameters\n    # echo 4096 > node0_start_addr\n    # echo 8192 > node0_end_addr\n    # echo 8192 > node1_start_addr\n    # echo 81920 > node1_end_addr\n    # echo 0 > node0_mem_free_bp\n    # echo Y > enabled\n    # dmesg -w\n    [...]\n    [18792.235916] Oops: divide error: 0000 [#1] SMP NOPTI\n    [...]\n    [18792.242787] RIP: 0010:damos_quota_score+0x6f/0x480\n    [...]\n\nThis issue was discovered [1] by Sashiko.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}