{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-97918","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-25T10:18:58.202Z","datePublished":"2026-09-25T10:22:39.162Z","dateUpdated":"2026-10-03T11:00:30.629Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-10-03T11:00:30.629Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Undo the registration when enabling the histogram trigger fails\n\nCommit 6f86bdeab633 (\"tracing: Fix bad hist from corrupting named_triggers\nlist\") described how a trigger that is registered but not on file->triggers\nends up freed while still on the global named_triggers list, and moved the\nregistration down so that hist_trigger_enable() follows it immediately. One\npath still gets there. hist_trigger_enable() adds the trigger and takes it\nstraight back out when the event cannot be enabled:\n\n\tlist_add_tail_rcu(&data->list, &file->triggers);\n\n\tupdate_cond_flag(file);\n\n\tif (trace_event_trigger_enable_disable(file, 1) < 0) {\n\t\tlist_del_rcu(&data->list);\n\t\tupdate_cond_flag(file);\n\t\tret--;\n\t}\n\nso the list walk in hist_unregister_trigger() matches nothing, test stays\nNULL, and the ->free() that would call del_named_trigger() is skipped.\nout_unreg falls through to out_free, which frees the trigger anyway:\n\n BUG: KASAN: slab-use-after-free in find_named_trigger+0xac/0xc0\n Read of size 8 at addr ffff8880091d3160 by task init/1\n  find_named_trigger+0xac/0xc0\n  hist_register_trigger+0xc1/0xa00\n  event_hist_trigger_parse+0x3146/0x6af0\n  event_trigger_write+0xce/0x160\n Freed by task 69:\n  kfree+0x154/0x420\n  trigger_kthread_fn+0xfd/0x160\n\nLeave the trigger where hist_unregister_trigger() can find it and let that\nundo the registration, which is the only code that knows all of what\ncmd_ops->init() took: the named list entry, the hist_pad reference, the\nreference on the trigger a named histogram is shared with, and the copied\ncmd_ops. It also pairs the failed trace_event_trigger_enable_disable(),\nwhose sm_ref and buffered event reference are otherwise left behind.\n\nSince ->free() releases trigger_data and, for a trigger that does not share\nits histogram, hist_data with it, out_unreg can no longer fall through to\nout_free. For a trigger that does share, hist_register_trigger() has\nalready destroyed the caller's hist_data, so the fall-through was reading\nfreed memory there as well.\n\nMove the enable_timestamps check in hist_unregister_trigger() above the\n->free() call for the same reason: hist_data does not outlive it once the\ntrigger being removed is the one that owns it."}],"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":"067fe038e70f6e64960d26a79c4df5f1413d0f13","lessThan":"c7ee2d5733574d4694f7c0035e4381f54c1fca27","status":"affected","versionType":"git"},{"version":"067fe038e70f6e64960d26a79c4df5f1413d0f13","lessThan":"51b07104d563d4be2be34158d3b9d922ca417642","status":"affected","versionType":"git"},{"version":"067fe038e70f6e64960d26a79c4df5f1413d0f13","lessThan":"bfa6bc11aef93a3d9db0ac9564b734849a9d959b","status":"affected","versionType":"git"},{"version":"067fe038e70f6e64960d26a79c4df5f1413d0f13","lessThan":"92383cef66791a0c63a2f27755cadbdb2fbf270b","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":"6.12.112","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.53","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.7","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc3","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":"6.12.112"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"6.18.53"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"7.2.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"7.3-rc3"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/c7ee2d5733574d4694f7c0035e4381f54c1fca27"},{"url":"https://git.kernel.org/stable/c/51b07104d563d4be2be34158d3b9d922ca417642"},{"url":"https://git.kernel.org/stable/c/bfa6bc11aef93a3d9db0ac9564b734849a9d959b"},{"url":"https://git.kernel.org/stable/c/92383cef66791a0c63a2f27755cadbdb2fbf270b"}],"title":"tracing: Undo the registration when enabling the histogram trigger fails","x_generator":{"engine":"bippy-1.2.0"}}}}