{"id":"AZL-110444","summary":"CVE-2026-93093 affecting package kernel 6.6.157.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nfirmware: arm_scmi: Publish channel state before callbacks\n\nTransport setup can enable callbacks before the setup routine returns.\nmailbox_chan_setup() registers the mailbox client with\nmbox_request_channel(), and the mailbox controller startup path can enable\ninterrupt delivery before SCMI mailbox channel state has been published.\nSimilarly, smc_chan_setup() requests the optional A2P completion IRQ before\nthe SMC transport has made its cinfo pointer visible.\n\nIf a pending or spurious callback fires in those windows, the transport RX\ncallback can dereference a NULL transport cinfo pointer. Publishing only\nthe transport-private pointer is not sufficient either: an early callback\ncan enter the SCMI core before scmi_chan_setup() has assigned\ncinfo-\u003ehandle.\nThe core derives scmi_info from cinfo-\u003ehandle in the RX path, so a NULL\nhandle can still fault even when the transport-private cinfo is valid.\n\nAssign cinfo-\u003ehandle before invoking the transport setup callback. Publish\nthe mailbox and SMC transport-private channel state before requesting the\nmailbox channels or IRQ, and clear the early-published pointers again on\nsetup failure. Also unwind mailbox setup devres resources on failure so an\noptional RX setup error that is ignored by the core does not leave stale\ntransport state behind.","modified":"2026-10-28T05:32:34Z","published":"2026-09-17T17:18:03Z","upstream":["CVE-2026-93093"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93093"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.157.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-110444.json"}}],"schema_version":"1.9.2"}