CVE-2026-46106

About vulnerability

In the Linux kernel, the following vulnerability has been resolved: eventfs: Hold eventfs_mutex and SRCU when remount walks events Commit 340f0c7067a9 (“eventfs: Update all the eventfs_inodes from the events descriptor”) had eventfs_set_attrs() recurse through ei->children on remount. The walk only holds the rcu_read_lock() taken by tracefs_apply_options() over tracefs_inodes, which is wrong:

• list_for_each_entry over ei->children races with the list_del_rcu() in eventfs_remove_rec() – LIST_POISON1 deref, same shape as d2603279c7d6.
• eventfs_inodes are freed via call_srcu(&eventfs_srcu, …). rcu_read_lock() does not extend an SRCU grace period, so ti->private can be reclaimed under the walk.
• The writes to ei->attr race with eventfs_set_attr(), which holds eventfs_mutex. Reproducer: while :; do mount -o remount,uid=$((RANDOM%1000)) /sys/kernel/tracing; done & while :; do echo “p:kp submit_bio” > /sys/kernel/tracing/kprobe_events echo > /sys/kernel/tracing/kprobe_events done Wrap the events portion of tracefs_apply_options() in eventfs_remount_lock()/_unlock() that take eventfs_mutex and srcu_read_lock(&eventfs_srcu). eventfs_set_attrs() doesn’t sleep so the nested rcu_read_lock() is fine; lockdep_assert_held() pins the contract. Comment in tracefs_drop_inode() said “RCU cycle” – it is SRCU. A flaw was found in the Linux kernel’s eventfs component. This vulnerability allows a local attacker to trigger a race condition during remount operations. By exploiting insufficient locking mechanisms when processing event descriptors, an attacker can cause memory corruption, leading to a denial of service (DoS) and system instability.

Live-patch status from KernelCare for each operating system.