{"id":"CVE-2026-68217","title":"media: pwc: Drain fill_buf on start_streaming() failure","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: pwc: Drain fill_buf on start_streaming() failure\n\npwc_isoc_init() submits its isochronous URBs with\nusb_submit_urb(.., GFP_KERNEL) in a loop. After the first URB…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < 97f3c15957ec7e6d249f05407ad947c0644df24d","Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < a4afffd148991a826e8995362fb10cf8705c1130","Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < eabe9a59640698137d7382d5b549e95dc37f7565","Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < a56e7641e09bd80b976e944ae759109b86fd5b38","Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < acc789b2173070638cad89c2b61d33ed338be0dd","Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < 9afd605dcd96c7a45f338eded1de16679b30e1df","Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < 5d4812668b03f823b5044789d6aa77fe56b42587","Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < 906e410dcffbbd99fb4081abab817a830033aa28","Linux 3.1"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-06T16:44:48.652931Z"},"published":"2026-08-10","updated":"2026-11-06","sourceUpdated":"2026-11-06T16:55:09.601Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-68217","references":[{"url":"https://git.kernel.org/stable/c/97f3c15957ec7e6d249f05407ad947c0644df24d"},{"url":"https://git.kernel.org/stable/c/a4afffd148991a826e8995362fb10cf8705c1130"},{"url":"https://git.kernel.org/stable/c/eabe9a59640698137d7382d5b549e95dc37f7565"},{"url":"https://git.kernel.org/stable/c/a56e7641e09bd80b976e944ae759109b86fd5b38"},{"url":"https://git.kernel.org/stable/c/acc789b2173070638cad89c2b61d33ed338be0dd"},{"url":"https://git.kernel.org/stable/c/9afd605dcd96c7a45f338eded1de16679b30e1df"},{"url":"https://git.kernel.org/stable/c/5d4812668b03f823b5044789d6aa77fe56b42587"},{"url":"https://git.kernel.org/stable/c/906e410dcffbbd99fb4081abab817a830033aa28"}],"tags":["cve.org"],"epss":0.0022,"epssPercentile":0.12607,"ingestedAt":"2026-11-06T18:00:12.620Z","slug":"CVE-2026-68217","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nmedia: pwc: Drain fill_buf on start_streaming() failure\n\npwc_isoc_init() submits its isochronous URBs with\nusb_submit_urb(.., GFP_KERNEL) in a loop. After the first URB is\nsubmitted, its completion handler pwc_isoc_handler() can run on another\nCPU before the loop finishes:\n\n  start_streaming()\n    pwc_isoc_init()\n      usb_submit_urb(urbs[0], GFP_KERNEL)\n                                  pwc_isoc_handler(urbs[0])\n                                    pdev->fill_buf =\n                                      pwc_get_next_fill_buf(pdev)\n      usb_submit_urb(urbs[i>0], ..)  -> fails\n      pwc_isoc_cleanup(pdev)           /* kills URBs */\n      return ret;\n    pwc_cleanup_queued_bufs(pdev, VB2_BUF_STATE_QUEUED)\n\npwc_get_next_fill_buf() detaches a buffer from pdev->queued_bufs and\nstores it in pdev->fill_buf. The error path in start_streaming() only\ndrains pdev->queued_bufs, so the buffer parked in pdev->fill_buf is\nleaked. vb2_start_streaming() then triggers\nWARN_ON(owned_by_drv_count).\n\nstop_streaming() already handles this since commit 80b0963e1698\n(\"[media] pwc: fix WARN_ON\"), which added the fill_buf drain in the\nteardown path but not in the start_streaming() error path. Mirror that\nhandling on failure so start_streaming() returns with no buffer owned\nby the driver.\n\nIssue identified by automated review of the INV-003 series at\nhttps://sashiko.dev/\n\n## Affected\n\n- `Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < 97f3c15957ec7e6d249f05407ad947c0644df24d`\n- `Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < a4afffd148991a826e8995362fb10cf8705c1130`\n- `Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < eabe9a59640698137d7382d5b549e95dc37f7565`\n- `Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < a56e7641e09bd80b976e944ae759109b86fd5b38`\n- `Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < acc789b2173070638cad89c2b61d33ed338be0dd`\n- `Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < 9afd605dcd96c7a45f338eded1de16679b30e1df`\n- `Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < 5d4812668b03f823b5044789d6aa77fe56b42587`\n- `Linux >= 885fe18f5542fe283a17f70583383c6cadcba1c3 < 906e410dcffbbd99fb4081abab817a830033aa28`\n- `Linux 3.1`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}