{"id":"AZL-110429","summary":"CVE-2026-74337 affecting package kernel 6.6.157.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix NMI/tracepoint re-entry deadlock on lru locks\n\nNMI and tracepoint BPF programs can re-enter the per-CPU or global\nLRU lock that bpf_lru_pop_free()/push_free() already hold on the\nsame CPU, AA-deadlocking. Lockdep reports \"inconsistent\n{INITIAL USE} -\u003e {IN-NMI}\" on &l-\u003elock (syzbot c69a0a2c816716f1e0d5)\nand \"possible recursive locking detected\" on &loc_l-\u003elock (syzbot\n18b26edb69b2e19f3b33).\n\nPrior trylock and rqspinlock based fixes (see links) were nacked\nbecause compromised on reliability.\n\nThis patch converts every LRU lock site to rqspinlock_t and adds a\nrecovery path for some failure windows to avoid node leaks.\n\nFailure recovery:\n\n - *_pop_free top-level: return NULL; prealloc_lru_pop() already\n   treats that as no-free-element (-ENOMEM).\n\n - Cross-CPU steal: skip the victim's locked loc_l, try next CPU.\n\n - Post-steal local lock fail: publish stolen node to lockless\n   per-CPU free_llist; next pop on this CPU picks it up.\n\n - push_free fail: mark node pending_free=1. __local_list_flush(),\n   __local_list_pop_pending() reclaim the node from pending_list.\n   __bpf_lru_list_shrink_inactive() reclaims the node from inactive\n   list. Nodes from active list are reclaimed by __bpf_lru_list_shrink()\n   or after __bpf_lru_list_rotate_active() demotes it to the inactive.","modified":"2026-10-29T05:34:21Z","published":"2026-08-15T06:22:34Z","upstream":["CVE-2026-74337"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74337"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.157.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-110429.json"}}],"schema_version":"1.9.2"}