{"cve":"CVE-2026-43292","nvd":{"published":"2026-05-08T14:16:36.250","modified":"2026-06-17T10:49:19.523","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/vmalloc: prevent RCU stalls in kasan_release_vmalloc_node\n\nWhen CONFIG_PAGE_OWNER is enabled, freeing KASAN shadow pages during\nvmalloc cleanup triggers expensive stack unwinding that acquires RCU read\nlocks.  Processing a large purge_list without rescheduling can cause the\ntask to hold CPU for extended periods (10+ seconds), leading to RCU stalls\nand potential OOM conditions.\n\nThe issue manifests in purge_vmap_node() -> kasan_release_vmalloc_node()\nwhere iterating through hundreds or thousands of vmap_area entries and\nfreeing their associated shadow pages causes:\n\n  rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:\n  rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6229/1:b..l\n  ...\n  task:kworker/0:17 state:R running task stack:28840 pid:6229\n  ...\n  kasan_release_vmalloc_node+0x1ba/0xad0 mm/vmalloc.c:2299\n  purge_vmap_node+0x1ba/0xad0 mm/vmalloc.c:2299\n\nEach call to kasan_release_vmalloc() can free many pages, and with\npage_owner tracking, each free triggers save_stack() which performs stack\nunwinding under RCU read lock.  Without yielding, this creates an\nunbounded RCU critical section.\n\nAdd periodic cond_resched() calls within the loop to allow:\n- RCU grace periods to complete\n- Other tasks to run\n- Scheduler to preempt when needed\n\nThe fix uses need_resched() for immediate response under load, with a\nbatch count of 32 as a guaranteed upper bound to prevent worst-case stalls\neven under light load.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/1afe45f89d54b7183768ebbbbf14238ec187ab5c","https://git.kernel.org/stable/c/2efa9c02c9b4c0d6866aa445f11056809b25ca28","https://git.kernel.org/stable/c/5747435e0fd474c24530ef1a6822f47e7d264b27","https://git.kernel.org/stable/c/b351fbe71091f7c8676c8ba597653d08b6719447"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:33:55.586217763+00:00"},"epss":{"cve":"CVE-2026-43292","score":0.00122,"percentile":0.0195,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}