{"id":"CVE-2026-72390","revision":"259f11f9acd24197a27eec0272f034ae","records":[{"revision":"259f11f9acd24197a27eec0272f034ae","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-72390","aliases":[],"title":"net/sched: sch_teql: Introduce slaves_lock to avoid race condition and UAF","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_teql: Introduce slaves_lock to avoid race condition and UAF\n\nThe teql master->slaves singly linked list is not protected against\nmultiple writes. It can be mod'ed concurently from teql_master_xmit(),\nteql_dequeue(), teql_init() and teql_destroy() without holding any list\nlock or RCU protection.\n\nzdi-disclosures@trendmicro.com has demonstrated that the qdisc is freed\nafter an RCU grace period, but teql_master_xmit() running on another\nCPU can still hold a stale pointer into the list, resulting in a\nslab-use-after-free:\n\nBUG: KASAN: slab-use-after-free in teql_master_xmit+0xf0f/0x16b0\nRead of size 8 at addr ffff888013fb0440 by task poc/332\nFreed 512-byte region [ffff888013fb0400, ffff888013fb0600) (kmalloc-512)\n\nThe fix?\nAdd a per-master slaves_lock spinlock that serializes all mutations of\nmaster->slaves and the NEXT_SLAVE() links in teql_destroy() and\nteql_qdisc_init(). teql_master_xmit() also takes the same slaves_lock\naround those updates.\nAnnotate master->slaves and the per-slave ->next pointer with __rcu and\nuse the appropriate RCU accessors everywhere they are touched:\nrcu_assign_pointer() on the writer side (under slaves_lock),\nrcu_dereference_protected() for the writer-side loads (also under\nslaves_lock), rcu_dereference_bh() for the loads in teql_master_xmit() and\nrtnl_dereference() for the loads in teql_master_open()/teql_master_mtu(),\nwhich run under RTNL.\nPair this with rcu_read_lock_bh()/rcu_read_unlock_bh() around the list\ntraversal in teql_master_xmit(), so that readers either observe a fully\nlinked list or are deferred until the in-flight mutation completes. The two\nearly-return paths in teql_master_xmit() are updated to release the RCU-bh\nread-side critical section before returning, since leaving it held would\ndisable BH on that CPU for good.","state":0,"publishedAt":"2026-08-15T05:56:19.186+00:00","modifiedAt":"2026-10-16T18:55:21.25+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"unaffected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"net/sched/sch_teql.c\"\n ],\n \"versions\": [\n {\n \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n \"lessThan\": \"03c67781254c574ae7fa75e881239a78473bdf42\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n \"lessThan\": \"735567bde7401f82b064f9f107b52ee1bf84ed8c\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n \"lessThan\": \"11402e6e18e96df615cbcc58157818dd604b23ff\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n \"lessThan\": \"9b7d05cbaa60108642402100efa6aa288dd33023\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n \"lessThan\": \"b26aa9d993537a4c3167d8ceead3b7c69c3a0aac\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n \"lessThan\": \"e5b811fe793166aecc59b085c1b7c31262ef2316\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n }\n ]\n }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"affected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"net/sched/sch_teql.c\"\n ],\n \"versions\": [\n {\n \"version\": \"2.6.12\",\n \"status\": \"affected\"\n },\n {\n \"version\": \"0\",\n \"lessThan\": \"2.6.12\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.1.178\",\n \"lessThanOrEqual\": \"6.1.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.6.145\",\n \"lessThanOrEqual\": \"6.6.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.12.97\",\n \"lessThanOrEqual\": \"6.12.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.18.40\",\n \"lessThanOrEqual\": \"6.18.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.1.5\",\n \"lessThanOrEqual\": \"7.1.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.2\",\n \"lessThanOrEqual\": \"*\",\n \"status\": \"unaffected\",\n \"versionType\": \"original_commit_for_fix\"\n }\n ]\n }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/03c67781254c574ae7fa75e881239a78473bdf42","https://git.kernel.org/stable/c/735567bde7401f82b064f9f107b52ee1bf84ed8c","https://git.kernel.org/stable/c/11402e6e18e96df615cbcc58157818dd604b23ff","https://git.kernel.org/stable/c/9b7d05cbaa60108642402100efa6aa288dd33023","https://git.kernel.org/stable/c/b26aa9d993537a4c3167d8ceead3b7c69c3a0aac","https://git.kernel.org/stable/c/e5b811fe793166aecc59b085c1b7c31262ef2316"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-72390","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-72390","identifiers":["CVE-2026-72390"]},"retained":false,"historicalAffected":[]}],"coverage":[]}