{"id":"CVE-2026-46106","state":"PUBLISHED","title":"eventfs: Hold eventfs_mutex and SRCU when remount walks events","description":"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->children\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->children 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->private\n    can be reclaimed under the walk.\n  - The writes to ei->attr 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\" > /sys/kernel/tracing/kprobe_events\n      echo > /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.","publishedAt":"2026-05-28T09:35:11.034Z","updatedAt":"2026-06-14T17:54:53.367Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"7ec535ed8724d18ae4e714d2277a5b89450659d2","status":"affected","lessThan":"ae9cd0b46b1890040006a2fc5e905c5d6053fd02","versionType":"git"},{"version":"340f0c7067a95281ad13734f8225f49c6cf52067","status":"affected","lessThan":"44e64d8a432837308f4dda3ffe819f1ec092a0ba","versionType":"git"},{"version":"340f0c7067a95281ad13734f8225f49c6cf52067","status":"affected","lessThan":"52b109f1b875b912d4ab2c5fdd8c322d47119d9b","versionType":"git"},{"version":"340f0c7067a95281ad13734f8225f49c6cf52067","status":"affected","lessThan":"ed2ad73bcb0a7a6cc934097d4853b6d5124c317e","versionType":"git"},{"version":"340f0c7067a95281ad13734f8225f49c6cf52067","status":"affected","lessThan":"07004a8c4b572171934390148ee48c4175c77eed","versionType":"git"},{"version":"99b86d85f7c73d676c50e8c35748f94dd41389da","status":"affected","versionType":"git"},{"version":"6.6.35","status":"affected","lessThan":"6.6.140","versionType":"semver"},{"version":"6.9.6","status":"affected","lessThan":"6.10","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/tracefs/event_inode.c","fs/tracefs/inode.c","fs/tracefs/internal.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.10","versionType":"semver"},{"version":"6.6.140","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.88","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.30","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.7","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/tracefs/event_inode.c","fs/tracefs/inode.c","fs/tracefs/internal.h"]}],"references":["https://git.kernel.org/stable/c/ae9cd0b46b1890040006a2fc5e905c5d6053fd02","https://git.kernel.org/stable/c/44e64d8a432837308f4dda3ffe819f1ec092a0ba","https://git.kernel.org/stable/c/52b109f1b875b912d4ab2c5fdd8c322d47119d9b","https://git.kernel.org/stable/c/ed2ad73bcb0a7a6cc934097d4853b6d5124c317e","https://git.kernel.org/stable/c/07004a8c4b572171934390148ee48c4175c77eed"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/46xxx/CVE-2026-46106.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-46106","state":"PUBLISHED","datePublished":"2026-05-28T09:35:11.034Z","dateUpdated":"2026-06-14T17:54:53.367Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-05-13T15:03:33.097Z"},"containers":{"cna":{"title":"eventfs: Hold eventfs_mutex and SRCU when remount walks events","descriptions":[{"lang":"en","value":"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->children\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->children 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->private\n    can be reclaimed under the walk.\n  - The writes to ei->attr 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\" > /sys/kernel/tracing/kprobe_events\n      echo > /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."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"7ec535ed8724d18ae4e714d2277a5b89450659d2","status":"affected","lessThan":"ae9cd0b46b1890040006a2fc5e905c5d6053fd02","versionType":"git"},{"version":"340f0c7067a95281ad13734f8225f49c6cf52067","status":"affected","lessThan":"44e64d8a432837308f4dda3ffe819f1ec092a0ba","versionType":"git"},{"version":"340f0c7067a95281ad13734f8225f49c6cf52067","status":"affected","lessThan":"52b109f1b875b912d4ab2c5fdd8c322d47119d9b","versionType":"git"},{"version":"340f0c7067a95281ad13734f8225f49c6cf52067","status":"affected","lessThan":"ed2ad73bcb0a7a6cc934097d4853b6d5124c317e","versionType":"git"},{"version":"340f0c7067a95281ad13734f8225f49c6cf52067","status":"affected","lessThan":"07004a8c4b572171934390148ee48c4175c77eed","versionType":"git"},{"version":"99b86d85f7c73d676c50e8c35748f94dd41389da","status":"affected","versionType":"git"},{"version":"6.6.35","status":"affected","lessThan":"6.6.140","versionType":"semver"},{"version":"6.9.6","status":"affected","lessThan":"6.10","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/tracefs/event_inode.c","fs/tracefs/inode.c","fs/tracefs/internal.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.10","versionType":"semver"},{"version":"6.6.140","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.88","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.30","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.7","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/tracefs/event_inode.c","fs/tracefs/inode.c","fs/tracefs/internal.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/ae9cd0b46b1890040006a2fc5e905c5d6053fd02"},{"url":"https://git.kernel.org/stable/c/44e64d8a432837308f4dda3ffe819f1ec092a0ba"},{"url":"https://git.kernel.org/stable/c/52b109f1b875b912d4ab2c5fdd8c322d47119d9b"},{"url":"https://git.kernel.org/stable/c/ed2ad73bcb0a7a6cc934097d4853b6d5124c317e"},{"url":"https://git.kernel.org/stable/c/07004a8c4b572171934390148ee48c4175c77eed"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-06-14T17:54:53.367Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6.35","versionEndExcluding":"6.6.140"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"6.12.88"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"6.18.30"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"7.0.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"7.1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.9.6"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}