{"id":"CVE-2022-50307","state":"PUBLISHED","title":"s390/cio: fix out-of-bounds access on cio_ignore free","description":"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_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.","publishedAt":"2025-09-15T14:46:02.608Z","updatedAt":"2026-05-11T19:16:46.881Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"172da89ed0eaf9d9348f5decb86ad04c624b39d1","status":"affected","lessThan":"0e501fd0f38e42304bfa0d46a812d93f80294a87","versionType":"git"},{"version":"172da89ed0eaf9d9348f5decb86ad04c624b39d1","status":"affected","lessThan":"106ab66cf5467726ca5ead51623043d37c06820a","versionType":"git"},{"version":"172da89ed0eaf9d9348f5decb86ad04c624b39d1","status":"affected","lessThan":"1b6074112742f65ece71b0f299ca5a6a887d2db6","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/s390/cio/css.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.15","versionType":"semver"},{"version":"5.15.78","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.0.7","status":"unaffected","lessThanOrEqual":"6.0.*","versionType":"semver"},{"version":"6.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/s390/cio/css.c"]}],"references":["https://git.kernel.org/stable/c/0e501fd0f38e42304bfa0d46a812d93f80294a87","https://git.kernel.org/stable/c/106ab66cf5467726ca5ead51623043d37c06820a","https://git.kernel.org/stable/c/1b6074112742f65ece71b0f299ca5a6a887d2db6"],"weaknesses":[],"ingestedAt":"2026-10-29T20:05:26.763Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2022/50xxx/CVE-2022-50307.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2022-50307","state":"PUBLISHED","datePublished":"2025-09-15T14:46:02.608Z","dateUpdated":"2026-05-11T19:16:46.881Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-09-15T14:18:36.813Z"},"containers":{"cna":{"title":"s390/cio: fix out-of-bounds access on cio_ignore free","descriptions":[{"lang":"en","value":"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_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."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"172da89ed0eaf9d9348f5decb86ad04c624b39d1","status":"affected","lessThan":"0e501fd0f38e42304bfa0d46a812d93f80294a87","versionType":"git"},{"version":"172da89ed0eaf9d9348f5decb86ad04c624b39d1","status":"affected","lessThan":"106ab66cf5467726ca5ead51623043d37c06820a","versionType":"git"},{"version":"172da89ed0eaf9d9348f5decb86ad04c624b39d1","status":"affected","lessThan":"1b6074112742f65ece71b0f299ca5a6a887d2db6","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/s390/cio/css.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.15","versionType":"semver"},{"version":"5.15.78","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.0.7","status":"unaffected","lessThanOrEqual":"6.0.*","versionType":"semver"},{"version":"6.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/s390/cio/css.c"]}],"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"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T19:16:46.881Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"5.15.78"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.0.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.1"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}