{"id":"CVE-2026-80854","revision":"182bf1f03f834bbb9bc1d0bed0b337c5","records":[{"revision":"182bf1f03f834bbb9bc1d0bed0b337c5","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-80854","aliases":[],"title":"usb: gadget: f_tcm: keep port count until LUN teardown completes","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_tcm: keep port count until LUN teardown completes\n\ntcm_usbg_drop_nexus() permits session removal once tpg_port_count\nreaches zero. However, usbg_port_unlink() currently decrements that\ncount from the fabric_pre_unlink() callback, before core_dev_del_lun()\nwaits for active se_lun references to drain.\n\nIf removal of the last LUN races a nexus removal, the latter can observe\na zero port count and call target_remove_session(). This frees\nsess_cmd_map while an in-flight struct usbg_cmd, including its work item,\ncan still be accessed.\n\nOverlapping the last-LUN unlink with nexus removal reproduces this\nlifetime violation as a DEBUG_OBJECTS \"free active\" warning for\nusbg_cmd_work, followed by a target-core BUG/Oops.\n\nThe generic target-core unlink path has no callback after\ncore_dev_del_lun() completes. Add an optional fabric_post_unlink()\ncallback and use it for the f_tcm port count. The count now remains\nnonzero until core_dev_del_lun() has finished draining active LUN\nreferences, preventing nexus removal from freeing the session during\ncommand completion.","state":0,"publishedAt":"2026-09-04T15:55:06.478+00:00","modifiedAt":"2026-10-19T08:44:48.32+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                        \"drivers/target/target_core_fabric_configfs.c\",\n                        \"drivers/usb/gadget/function/f_tcm.c\",\n                        \"include/target/target_core_fabric.h\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"c52661d60f636d17e26ad834457db333bd1df494\",\n                            \"lessThan\": \"c494c5562ca69b61a82f566e3b87a445d2c28929\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c52661d60f636d17e26ad834457db333bd1df494\",\n                            \"lessThan\": \"c1f359d9a5efed458946063de65ddbeaacc4f165\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c52661d60f636d17e26ad834457db333bd1df494\",\n                            \"lessThan\": \"178f59a0bccd3f66cdfa5184310f31a58b7257c4\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c52661d60f636d17e26ad834457db333bd1df494\",\n                            \"lessThan\": \"ad6f0375d2e93a1d8c015463e5e92dfcb26e311b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c52661d60f636d17e26ad834457db333bd1df494\",\n                            \"lessThan\": \"2efbfd42441d3ef8137aff2d59e9835e1d5ae780\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c52661d60f636d17e26ad834457db333bd1df494\",\n                            \"lessThan\": \"85aa61fedcb4eb13f3dc5db73f6dc359f41f5d95\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c52661d60f636d17e26ad834457db333bd1df494\",\n                            \"lessThan\": \"bbd6aa311a9f4dd17822c7557451458d3d2e980b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c52661d60f636d17e26ad834457db333bd1df494\",\n                            \"lessThan\": \"eaa96a8458f54d6cf0954242ab8b1df2a6fccafa\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c52661d60f636d17e26ad834457db333bd1df494\",\n                            \"lessThan\": \"c39d0916da47d94909391876c9e5bd429ea7b1b9\",\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                        \"drivers/target/target_core_fabric_configfs.c\",\n                        \"drivers/usb/gadget/function/f_tcm.c\",\n                        \"include/target/target_core_fabric.h\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"3.5\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"3.5\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.269\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.220\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.187\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.156\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.108\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.49\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1.13\",\n                            \"lessThanOrEqual\": \"7.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.3\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/c494c5562ca69b61a82f566e3b87a445d2c28929","https://git.kernel.org/stable/c/c1f359d9a5efed458946063de65ddbeaacc4f165","https://git.kernel.org/stable/c/178f59a0bccd3f66cdfa5184310f31a58b7257c4","https://git.kernel.org/stable/c/ad6f0375d2e93a1d8c015463e5e92dfcb26e311b","https://git.kernel.org/stable/c/2efbfd42441d3ef8137aff2d59e9835e1d5ae780","https://git.kernel.org/stable/c/85aa61fedcb4eb13f3dc5db73f6dc359f41f5d95","https://git.kernel.org/stable/c/bbd6aa311a9f4dd17822c7557451458d3d2e980b","https://git.kernel.org/stable/c/eaa96a8458f54d6cf0954242ab8b1df2a6fccafa","https://git.kernel.org/stable/c/c39d0916da47d94909391876c9e5bd429ea7b1b9"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-80854","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-80854","identifiers":["CVE-2026-80854"]},"retained":false,"historicalAffected":[]}],"coverage":[]}