{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-99234","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-25T10:25:14.402Z","datePublished":"2026-11-02T16:06:41.083Z","dateUpdated":"2026-11-03T19:13:02.797Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-11-03T19:13:02.797Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Unregister field variable histograms when the command fails\n\nAn action that names a field on another event needs that field as a\nvariable, so create_field_var_hist() registers a second hist trigger on\nthat event to provide it, and records it in\ntarget_hist_data->field_var_hists[].\n\nIf a later part of the same command fails, create_actions() returns an\nerror and event_hist_trigger_parse() jumps to out_free. The write fails\nwith -EINVAL and sched_switch gets no trigger, but:\n\n  # echo 'hist:keys=pid:ts0=common_timestamp.usecs' >> \\\n      events/sched/sched_waking/trigger\n  # echo 'my_synth u64 lat; int a; int b' >> synthetic_events\n  # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:\\\n      onmatch(sched.sched_waking).my_synth($wakeup_lat,prio,nosuchfld)'\\\n      >> events/sched/sched_switch/trigger\n  # cat events/sched/sched_waking/trigger\n  hist:keys=pid:vals=hitcount:ts0=common_timestamp.usecs:sort=hitcount:size=2048:clock=global [active]\n  hist:keys=pid:vals=hitcount:synthetic_prio=prio:sort=hitcount:size=2048 [active]\n\nThe second histogram is the one created for 'prio'. It is still active and\nstill counting.\n\nout_free reaches destroy_field_var_hists(), which frees the\nfield_var_hists[] entries, but never unregister_field_var_hists(), which is\nwhat removes the triggers and runs only from event_hist_trigger_free(). The\nentry is freed and the trigger is left with nothing tracking it.\n\nUnregister the field variable histograms in out_free as well, and record\neach one as soon as its trigger is registered rather than after the lookup\nthat follows it, so no exit can leave a registered trigger untracked. The\nentry then belongs to field_var_hists[] and is released by\ndestroy_field_var_hists(), so freeing it on that exit would be a double\nfree."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/trace/trace_events_hist.c"],"versions":[{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","lessThan":"f21351d1c4cdcc6a68f03636a407c2af1a5e1e10","status":"affected","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","lessThan":"dba0f492703956801149cc70b39d2650a37995c3","status":"affected","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","lessThan":"a3d7ffd2409700748a495b645948fef48199206e","status":"affected","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","lessThan":"aae0ccd7326eef78dcdefffef3d1253e6f0615ca","status":"affected","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","lessThan":"8482ec5b65f606d5bbcec518e0afc69ad65ca414","status":"affected","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","lessThan":"431959fc76456cbba539279fe8967aa9391e6f23","status":"affected","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","lessThan":"5afb9317e2eeb1c7021a82995ce244fda5a4bd4f","status":"affected","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","lessThan":"d0090baf02dd08f6e909f36f0ad54a4e80f5e79b","status":"affected","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","lessThan":"91c14d6c13096091c56304120aaa26e479130b8b","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/trace/trace_events_hist.c"],"versions":[{"version":"4.17","status":"affected"},{"version":"0","lessThan":"4.17","status":"unaffected","versionType":"semver"},{"version":"5.10.273","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.224","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.191","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.161","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.115","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.60","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.14","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3.1","lessThanOrEqual":"7.3.*","status":"unaffected","versionType":"semver"},{"version":"7.4-rc1","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"5.10.273"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"5.15.224"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"6.6.161"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"6.12.115"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"6.18.60"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"7.2.14"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"7.3.1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"7.4-rc1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/f21351d1c4cdcc6a68f03636a407c2af1a5e1e10"},{"url":"https://git.kernel.org/stable/c/dba0f492703956801149cc70b39d2650a37995c3"},{"url":"https://git.kernel.org/stable/c/a3d7ffd2409700748a495b645948fef48199206e"},{"url":"https://git.kernel.org/stable/c/aae0ccd7326eef78dcdefffef3d1253e6f0615ca"},{"url":"https://git.kernel.org/stable/c/8482ec5b65f606d5bbcec518e0afc69ad65ca414"},{"url":"https://git.kernel.org/stable/c/431959fc76456cbba539279fe8967aa9391e6f23"},{"url":"https://git.kernel.org/stable/c/5afb9317e2eeb1c7021a82995ce244fda5a4bd4f"},{"url":"https://git.kernel.org/stable/c/d0090baf02dd08f6e909f36f0ad54a4e80f5e79b"},{"url":"https://git.kernel.org/stable/c/91c14d6c13096091c56304120aaa26e479130b8b"}],"title":"tracing: Unregister field variable histograms when the command fails","x_generator":{"engine":"bippy-1.2.0"}}}}