{"id":"CVE-2022-50307","title":"s390/cio: fix out-of-bounds access on cio_ignore free","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/cio: fix out-of-bounds access on cio_ignore free\n\nThe channel-subsystem-driver scans for newly available devices whenever\ndevice-IDs are removed from the cio_ignor…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 172da89ed0eaf9d9348f5decb86ad04c624b39d1 < 0e501fd0f38e42304bfa0d46a812d93f80294a87","Linux >= 172da89ed0eaf9d9348f5decb86ad04c624b39d1 < 106ab66cf5467726ca5ead51623043d37c06820a","Linux >= 172da89ed0eaf9d9348f5decb86ad04c624b39d1 < 1b6074112742f65ece71b0f299ca5a6a887d2db6","Linux 5.15"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-05T20:09:25.829483Z"},"published":"2025-09-15","updated":"2026-11-05","sourceUpdated":"2026-11-05T20:10:34.054Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2022-50307","references":[{"url":"https://git.kernel.org/stable/c/0e501fd0f38e42304bfa0d46a812d93f80294a87"},{"url":"https://git.kernel.org/stable/c/106ab66cf5467726ca5ead51623043d37c06820a"},{"url":"https://git.kernel.org/stable/c/1b6074112742f65ece71b0f299ca5a6a887d2db6"}],"tags":["cve.org"],"epss":0.00161,"epssPercentile":0.05319,"ingestedAt":"2026-11-05T22:38:31.723Z","slug":"CVE-2022-50307","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ns390/cio: fix out-of-bounds access on cio_ignore free\n\nThe channel-subsystem-driver scans for newly available devices whenever\ndevice-IDs are removed from the cio_ignore list using a command such as:\n\n  echo free >/proc/cio_ignore\n\nSince an I/O device scan might interfer with running I/Os, commit\n172da89ed0ea (\"s390/cio: avoid excessive path-verification requests\")\nintroduced an optimization to exclude online devices from the scan.\n\nThe newly added check for online devices incorrectly assumes that\nan I/O-subchannel's drvdata points to a struct io_subchannel_private.\nFor devices that are bound to a non-default I/O subchannel driver, such\nas the vfio_ccw driver, this results in an out-of-bounds read access\nduring each scan.\n\nFix this by changing the scan logic to rely on a driver-independent\nonline indication. For this we can use struct subchannel->config.ena,\nwhich is the driver's requested subchannel-enabled state. Since I/Os\ncan only be started on enabled subchannels, this matches the intent\nof the original optimization of not scanning devices where I/O might\nbe running.\n\n## Affected\n\n- `Linux >= 172da89ed0eaf9d9348f5decb86ad04c624b39d1 < 0e501fd0f38e42304bfa0d46a812d93f80294a87`\n- `Linux >= 172da89ed0eaf9d9348f5decb86ad04c624b39d1 < 106ab66cf5467726ca5ead51623043d37c06820a`\n- `Linux >= 172da89ed0eaf9d9348f5decb86ad04c624b39d1 < 1b6074112742f65ece71b0f299ca5a6a887d2db6`\n- `Linux 5.15`\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":[]}