{"id":"CVE-2026-46106","summary":"eventfs: Hold eventfs_mutex and SRCU when remount walks events","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":"2026-10-20T10:31:06.760617043Z","published":"2026-05-28T09:35:11.034Z","related":["openSUSE-SU-2026:10954-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46106.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/07004a8c4b572171934390148ee48c4175c77eed"},{"type":"WEB","url":"https://git.kernel.org/stable/c/44e64d8a432837308f4dda3ffe819f1ec092a0ba"},{"type":"WEB","url":"https://git.kernel.org/stable/c/52b109f1b875b912d4ab2c5fdd8c322d47119d9b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ae9cd0b46b1890040006a2fc5e905c5d6053fd02"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ed2ad73bcb0a7a6cc934097d4853b6d5124c317e"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46106.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-46106"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"7ec535ed8724d18ae4e714d2277a5b89450659d2"},{"fixed":"ae9cd0b46b1890040006a2fc5e905c5d6053fd02"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"340f0c7067a95281ad13734f8225f49c6cf52067"},{"fixed":"44e64d8a432837308f4dda3ffe819f1ec092a0ba"},{"fixed":"52b109f1b875b912d4ab2c5fdd8c322d47119d9b"},{"fixed":"ed2ad73bcb0a7a6cc934097d4853b6d5124c317e"},{"fixed":"07004a8c4b572171934390148ee48c4175c77eed"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6.6.35"},{"fixed":"6.6.140"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6.9.6"},{"fixed":"6.10"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"99b86d85f7c73d676c50e8c35748f94dd41389da"}]}],"versions":["v6.6.139","v6.6.138","v6.6.137","v6.6.136","v6.6.135","v6.6.134","v6.6.133","v6.6.132","v6.6.131","v6.6.130","v6.6.129","v6.6.128","v6.6.127","v6.6.126","v6.6.125","v6.6.124","v6.6.123","v6.6.122","v6.6.121","v6.6.120","v6.6.119","v6.6.118","v6.6.117","v6.6.116","v6.6.115","v6.6.114","v6.6.113","v6.6.112","v6.6.111","v6.6.110","v6.6.109","v6.6.108","v6.6.107","v6.6.106","v6.6.105","v6.6.104","v6.6.103","v6.6.102","v6.6.101","v6.6.100","v6.6.99","v6.6.98","v6.6.97","v6.6.96","v6.6.95","v6.6.94","v6.6.93","v6.6.92","v6.6.91","v6.6.90","v6.6.89","v6.6.88","v6.6.87","v6.6.86","v6.6.85","v6.6.84","v6.6.83","v6.6.82","v6.6.81","v6.6.80","v6.6.79","v6.6.78","v6.6.77","v6.6.76","v6.6.75","v6.6.74","v6.6.73","v6.6.72","v6.6.71","v6.6.70","v6.6.69","v6.6.68","v6.6.67","v6.6.66","v6.6.65","v6.6.64","v6.6.63","v6.6.62","v6.6.61","v6.6.60","v6.6.59","v6.6.58","v6.6.57","v6.6.56","v6.6.55","v6.6.54","v6.6.53","v6.6.52","v6.6.51","v6.6.50","v6.6.49","v6.6.48","v6.6.47","v6.6.46","v6.6.45","v6.6.44","v6.6.43","v6.6.42","v6.6.41","v6.6.40","v6.6.39","v6.6.38","v6.6.37","v6.6.36","v6.6.35","v6.9.12","v6.9.11","v6.9.10","v6.9.9","v6.9.8","v6.9.7","v6.9.6"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-46106.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.140"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.88"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.10.0"},{"fixed":"6.18.30"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"7.0.7"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-46106.json"}}],"schema_version":"1.9.0"}