{"id":"AZL-88953","summary":"CVE-2026-46106 affecting package kernel for versions less than 6.6.141.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\neventfs: Hold eventfs_mutex and SRCU when remount walks events\n\nCommit 340f0c7067a9 (\"eventfs: Update all the eventfs_inodes from the\nevents descriptor\") had eventfs_set_attrs() recurse through ei-\u003echildren\non remount.  The walk only holds the rcu_read_lock() taken by\ntracefs_apply_options() over tracefs_inodes, which is wrong:\n\n  - list_for_each_entry over ei-\u003echildren races with the list_del_rcu()\n    in eventfs_remove_rec() -- LIST_POISON1 deref, same shape as\n    d2603279c7d6.\n  - eventfs_inodes are freed via call_srcu(&eventfs_srcu, ...).\n    rcu_read_lock() does not extend an SRCU grace period, so ti-\u003eprivate\n    can be reclaimed under the walk.\n  - The writes to ei-\u003eattr race with eventfs_set_attr(), which holds\n    eventfs_mutex.\n\nReproducer:\n\n  while :; do mount -o remount,uid=$((RANDOM%1000)) /sys/kernel/tracing; done &\n  while :; do\n      echo \"p:kp submit_bio\" \u003e /sys/kernel/tracing/kprobe_events\n      echo \u003e /sys/kernel/tracing/kprobe_events\n  done\n\nWrap the events portion of tracefs_apply_options() in\neventfs_remount_lock()/_unlock() that take eventfs_mutex and\nsrcu_read_lock(&eventfs_srcu).  eventfs_set_attrs() doesn't sleep so the\nnested rcu_read_lock() is fine; lockdep_assert_held() pins the contract.\n\nComment in tracefs_drop_inode() said \"RCU cycle\" -- it is SRCU.","modified":"2026-08-28T17:48:10.017728092Z","published":"2026-05-28T10:16:25Z","upstream":["CVE-2026-46106"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-46106"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.141.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-88953.json"}}],"schema_version":"1.9.0"}