{"id":"AZL-72871","summary":"CVE-2025-68331 affecting package kernel for versions less than 6.6.119.3-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: uas: fix urb unmapping issue when the uas device is remove during ongoing data transfer\n\nWhen a UAS device is unplugged during data transfer, there is\na probability of a system panic occurring. The root cause is\nan access to an invalid memory address during URB callback handling.\nSpecifically, this happens when the dma_direct_unmap_sg() function\nis called within the usb_hcd_unmap_urb_for_dma() interface, but the\nsg-\u003edma_address field is 0 and the sg data structure has already been\nfreed.\n\nThe SCSI driver sends transfer commands by invoking uas_queuecommand_lck()\nin uas.c, using the uas_submit_urbs() function to submit requests to USB.\nWithin the uas_submit_urbs() implementation, three URBs (sense_urb,\ndata_urb, and cmd_urb) are sequentially submitted. Device removal may\noccur at any point during uas_submit_urbs execution, which may result\nin URB submission failure. However, some URBs might have been successfully\nsubmitted before the failure, and uas_submit_urbs will return the -ENODEV\nerror code in this case. The current error handling directly calls\nscsi_done(). In the SCSI driver, this eventually triggers scsi_complete()\nto invoke scsi_end_request() for releasing the sgtable. The successfully\nsubmitted URBs, when being unlinked to giveback, call\nusb_hcd_unmap_urb_for_dma() in hcd.c, leading to exceptions during sg\nunmapping operations since the sg data structure has already been freed.\n\nThis patch modifies the error condition check in the uas_submit_urbs()\nfunction. When a UAS device is removed but one or more URBs have already\nbeen successfully submitted to USB, it avoids immediately invoking\nscsi_done() and save the cmnd to devinfo-\u003ecmnd array. If the successfully\nsubmitted URBs is completed before devinfo-\u003eresetting being set, then\nthe scsi_done() function will be called within uas_try_complete() after\nall pending URB operations are finalized. Otherwise, the scsi_done()\nfunction will be called within uas_zap_pending(), which is executed after\nusb_kill_anchored_urbs().\n\nThe error handling only takes effect when uas_queuecommand_lck() calls\nuas_submit_urbs() and returns the error value -ENODEV . In this case,\nthe device is disconnected, and the flow proceeds to uas_disconnect(),\nwhere uas_zap_pending() is invoked to call uas_try_complete().","modified":"2026-04-01T05:22:13.356247Z","published":"2025-12-22T17:16:00Z","upstream":["CVE-2025-68331"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-68331"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.119.3-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-72871.json"}}],"schema_version":"1.7.5"}