{"affected":[{"defaultStatus":"unaffected","product":"Linux","source":"CNA: Linux","vendor":"Linux","versions":[{"lessThan":"0c8d4112df329bf3dfbf27693f918c3b08676538","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"6a818db0d5aecf80d4ba9e10ac153f60adc629ca","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"3a1c35d72dc0b34d1e746ed705790c0f630aa427","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"b545c0e1e4094d4de2bdfe9a3823f9154b0c0005","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"f59f5a269ca5e43c567aca7f1f52500a0186e9b7","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"6ffce7a92ef5c68f7e5d6f4d722c2f96280c064b","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"5398b8e275bf81a2517b327d216c0f37ac9ac5ae","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"4fe1ec995483737f3d2a14c3fe1d8fe634972979","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","source":"CNA: Linux","vendor":"Linux","versions":[{"status":"affected","version":"2.6.12"},{"lessThan":"2.6.12","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"4.9.*","status":"unaffected","version":"4.9.334","versionType":"semver"},{"lessThanOrEqual":"4.14.*","status":"unaffected","version":"4.14.300","versionType":"semver"},{"lessThanOrEqual":"4.19.*","status":"unaffected","version":"4.19.267","versionType":"semver"},{"lessThanOrEqual":"5.4.*","status":"unaffected","version":"5.4.225","versionType":"semver"},{"lessThanOrEqual":"5.10.*","status":"unaffected","version":"5.10.156","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.80","versionType":"semver"},{"lessThanOrEqual":"6.0.*","status":"unaffected","version":"6.0.10","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"6.1","versionType":"original_commit_for_fix"}]}],"cveId":"CVE-2022-49771","cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndm ioctl: fix misbehavior if list_versions races with module loading\n\n__list_versions will first estimate the required space using the\n\"dm_target_iterate(list_version_get_needed, &needed)\" call and then will\nfill the space using the \"dm_target_iterate(list_version_get_info,\n&iter_info)\" call. Each of these calls locks the targets using the\n\"down_read(&_lock)\" and \"up_read(&_lock)\" calls, however between the first\nand second \"dm_target_iterate\" there is no lock held and the target\nmodules can be loaded at this point, so the second \"dm_target_iterate\"\ncall may need more space than what was the first \"dm_target_iterate\"\nreturned.\n\nThe code tries to handle this overflow (see the beginning of\nlist_version_get_info), however this handling is incorrect.\n\nThe code sets \"param->data_size = param->data_start + needed\" and\n\"iter_info.end = (char *)vers+len\" - \"needed\" is the size returned by the\nfirst dm_target_iterate call; \"len\" is the size of the buffer allocated by\nuserspace.\n\n\"len\" may be greater than \"needed\"; in this case, the code will write up\nto \"len\" bytes into the buffer, however param->data_size is set to\n\"needed\", so it may write data past the param->data_size value. The ioctl\ninterface copies only up to param->data_size into userspace, thus part of\nthe result will be truncated.\n\nFix this bug by setting \"iter_info.end = (char *)vers + needed;\" - this\nguarantees that the second \"dm_target_iterate\" call will write only up to\nthe \"needed\" buffer and it will exit with \"DM_BUFFER_FULL_FLAG\" if it\noverflows the \"needed\" space - in this case, userspace will allocate a\nlarger buffer and retry.\n\nNote that there is also a bug in list_version_get_needed - we need to add\n\"strlen(tt->name) + 1\" to the needed size, not \"strlen(tt->name)\".","epss":{"date":"2026-11-05","percentile":0.05074,"score":0.00159},"exploits":[],"kev":null,"metrics":[],"modifiedAt":1793908182811,"publishedAt":1746108548813,"references":[{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/0c8d4112df329bf3dfbf27693f918c3b08676538"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/6a818db0d5aecf80d4ba9e10ac153f60adc629ca"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/3a1c35d72dc0b34d1e746ed705790c0f630aa427"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/b545c0e1e4094d4de2bdfe9a3823f9154b0c0005"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/f59f5a269ca5e43c567aca7f1f52500a0186e9b7"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/6ffce7a92ef5c68f7e5d6f4d722c2f96280c064b"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/5398b8e275bf81a2517b327d216c0f37ac9ac5ae"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/4fe1ec995483737f3d2a14c3fe1d8fe634972979"}],"remediation":[],"revision":"09bb0261d56ef0de67f93cd00c27782baf7c0c242eea22563fce81a38bdc1ecb","sources":[{"modifiedAt":1793908182811,"name":"CNA: Linux","retrievedAt":1793909398749,"url":"https://www.cve.org/CVERecord?id=CVE-2022-49771"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1793909406504,"url":"https://api.first.org/data/v1/epss?cve=CVE-2022-49771"}],"ssvc":{"assessedAt":1793908030840,"automatable":"no","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"partial"},"status":"published","title":"dm ioctl: fix misbehavior if list_versions races with module loading","updatedAt":1793909406504}