{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-89759", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.763Z", "datePublished": "2026-09-11T19:47:01.313Z", "dateUpdated": "2026-10-19T08:52:12.812Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:52:12.812Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/kmemleak: avoid soft lockup when scanning task stacks\n\nPatch series \"mm/kmemleak: avoid soft lockup when scanning task\", v3.\n\nkmemleak_scan() scans every task stack under one rcu_read_lock() with no\nreschedule point, which can trip the soft lockup watchdog on hosts with\nvery many threads.\n\nThat prints the following message, depending on the workload+host\nconfiguration:\n\n watchdog: BUG: soft lockup - CPU#35 stuck for 22s! [kmemleak:537]\n scan_block\n kmemleak_scan\n kmemleak_scan_thread\n kthread\n\nPatch 1 walks the tasks with find_ge_pid() so the scan reschedules between\ntasks\n\nPatches 2-3 let the scan loops stop early once a scan is interrupted.\n\n\nThis patch (of 3):\n\nkmemleak_scan() walks every thread and scans its kernel stack under a\nsingle rcu_read_lock() with no reschedule point. On a host with very many\nthreads -- amplified by KASAN/lockdep in debug builds -- this loop can hog\na CPU long enough to trip the soft lockup watchdog:\n\n watchdog: BUG: soft lockup - CPU#35 stuck for 22s! [kmemleak:537]\n scan_block\n kmemleak_scan\n kmemleak_scan_thread\n kthread\n\nA cond_resched() cannot be added directly: the loop runs inside an RCU\nread-side critical section.\n\nWalk the tasks one PID at a time with find_ge_pid(), taking the RCU read\nlock only to look up and pin each task. The stack is then scanned with no\nlock held, so cond_resched() runs between tasks and the scan stops early\non scan_should_stop(). This follows the next_tgid()/task_seq_get_next()\niteration pattern and keeps each RCU critical section short." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "mm/kmemleak.c" ], "versions": [ { "version": "c4b28963fd79457315783b3b0f21c01eb88cfdc1", "lessThan": "9a1b12c06c192290b8479de48f66f1e75d89c4b7", "status": "affected", "versionType": "git" }, { "version": "c4b28963fd79457315783b3b0f21c01eb88cfdc1", "lessThan": "3fc8044251de21555fb02c365fa681bab8b0db55", "status": "affected", "versionType": "git" }, { "version": "c4b28963fd79457315783b3b0f21c01eb88cfdc1", "lessThan": "1838c704bcb4fd3556cf67513c6f97a39099e35c", "status": "affected", "versionType": "git" }, { "version": "c4b28963fd79457315783b3b0f21c01eb88cfdc1", "lessThan": "5d10d4e19e6daa487f0cd0ea6cba472325de92f9", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "mm/kmemleak.c" ], "versions": [ { "version": "5.10", "status": "affected" }, { "version": "0", "lessThan": "5.10", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.109", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.50", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.4", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10", "versionEndExcluding": "6.12.109" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10", "versionEndExcluding": "6.18.50" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10", "versionEndExcluding": "7.2.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/9a1b12c06c192290b8479de48f66f1e75d89c4b7" }, { "url": "https://git.kernel.org/stable/c/3fc8044251de21555fb02c365fa681bab8b0db55" }, { "url": "https://git.kernel.org/stable/c/1838c704bcb4fd3556cf67513c6f97a39099e35c" }, { "url": "https://git.kernel.org/stable/c/5d10d4e19e6daa487f0cd0ea6cba472325de92f9" } ], "title": "mm/kmemleak: avoid soft lockup when scanning task stacks", "x_generator": { "engine": "bippy-1.2.0" } } } }