{"id":"CVE-2026-98786","summary":"drm/amd/display: guard dc_sink dereferences in MST mode validation","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amd/display: guard dc_sink dereferences in MST mode validation\n\ndm_dp_mst_is_port_support_mode() reads\naconnector-\u003edc_sink-\u003edsc_caps... for the DSC branch-throughput check,\nand get_conv_frl_bw()'s HDMI-PCON FRL-bandwidth path reads\naconnector-\u003edc_sink-\u003eedid_caps.max_frl_rate, both without a NULL\ncheck. dc_sink is cleared asynchronously on MST unplug, and both\nfunctions run from paths that the driver's own comments document as\nracing that teardown: the connector probe worker's -\u003emode_valid\ncallback and a compositor's atomic check, neither of which holds the\nMST manager lock that the teardown path uses. The former does have an\nexisting dsc_aux NULL check, but dsc_aux isn't reliably cleared in\nevery path that clears dc_sink, so it doesn't cover this.\n\nFail the port-support check and skip the FRL conversion path when the\nsink is already gone.\n\n(cherry picked from commit 7c3db8da4e039698ae198c870712428644e965c7)","modified":"2026-10-19T02:47:24.929364772Z","published":"2026-10-18T15:48:22.989Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98786.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/217f64f348c90cba62164e7ff38e0ccf78a5ca09"},{"type":"WEB","url":"https://git.kernel.org/stable/c/daa0437fe5e451856aaf8fda602a9fc2105bbd54"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98786.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98786"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"f04d275d94e164d24516c32437c988a323018f63"},{"fixed":"daa0437fe5e451856aaf8fda602a9fc2105bbd54"},{"fixed":"217f64f348c90cba62164e7ff38e0ccf78a5ca09"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98786.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.0.0"},{"fixed":"7.2.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98786.json"}}],"schema_version":"1.9.0"}