{"id":"AZL-83828","summary":"CVE-2026-31579 affecting package kernel 6.6.150.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nwireguard: device: use exit_rtnl callback instead of manual rtnl_lock in pre_exit\n\nwg_netns_pre_exit() manually acquires rtnl_lock() inside the\npernet .pre_exit callback.  This causes a hung task when another\nthread holds rtnl_mutex - the cleanup_net workqueue (or the\nsetup_net failure rollback path) blocks indefinitely in\nwg_netns_pre_exit() waiting to acquire the lock.\n\nConvert to .exit_rtnl, introduced in commit 7a60d91c690b (\"net:\nAdd -\u003eexit_rtnl() hook to struct pernet_operations.\"), where the\nframework already holds RTNL and batches all callbacks under a\nsingle rtnl_lock()/rtnl_unlock() pair, eliminating the contention\nwindow.\n\nThe rcu_assign_pointer(wg-\u003ecreating_net, NULL) is safe to move\nfrom .pre_exit to .exit_rtnl (which runs after synchronize_rcu())\nbecause all RCU readers of creating_net either use maybe_get_net()\n- which returns NULL for a dying namespace with zero refcount - or\naccess net-\u003euser_ns which remains valid throughout the entire\nops_undo_list sequence.\n\n[ Jason: added __net_exit and __read_mostly annotations that were missing. ]","modified":"2026-08-31T05:26:27Z","published":"2026-04-24T15:16:32Z","upstream":["CVE-2026-31579"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31579"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.150.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-83828.json"}}],"schema_version":"1.9.0"}