{"id":"CVE-2026-93174","state":"PUBLISHED","title":"bpf: Copy per-CPU map value padding in copy_map_value_long()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Copy per-CPU map value padding in copy_map_value_long()\n\nIn kernel, per-CPU map elements are stored with\nround_up(map->value_size, 8) bytes. On UAPI lookup paths, it copies the\nrounded size for each CPU into a temporary buffer.\n\nHowever, copy_map_value_long() passes 'map->value_size' to\nbpf_obj_memcpy(). When the map has special fields, bpf_obj_memcpy() copies\naround those fields with memcpy(), and does not copy the tail padding\nbetween 'map->value_size' and round_up(map->value_size, 8).\n\nThe temporary UAPI lookup buffers are allocated without __GFP_ZERO. As a\nresult, when the per-CPU map's value size is not equal to\nround_up(map->value_size, 8), UAPI LOOKUP_ELEM and its variants can return\nstale heap contents from that padding to user space. The same issue\napplies to bpf_iter for per-CPU maps.\n\nPass round_up(map->value_size, 8) to bpf_obj_memcpy() from\ncopy_map_value_long(), so per-CPU maps both with and without special\nfields copy the entire per-CPU slot. Remove the now redundant round_up()\nfrom bpf_obj_memcpy()'s long_memcpy path.","publishedAt":"2026-09-17T16:12:03.946Z","updatedAt":"2026-10-30T12:36:14.183Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"448325199f574d33824dbf9121efb03558412966","status":"affected","lessThan":"e0653c8f718109d140e806daac166c43e2b2b8bd","versionType":"git"},{"version":"448325199f574d33824dbf9121efb03558412966","status":"affected","lessThan":"953e85da53541a8dc3e7ad4e8532f29a34a32eae","versionType":"git"},{"version":"448325199f574d33824dbf9121efb03558412966","status":"affected","lessThan":"003bf840ed3326bd01396ce7d5b431cef0d371e7","versionType":"git"},{"version":"448325199f574d33824dbf9121efb03558412966","status":"affected","lessThan":"5e9f69829835521aa2942d1d14bd0990fbc6991e","versionType":"git"},{"version":"448325199f574d33824dbf9121efb03558412966","status":"affected","lessThan":"ff3f22ed8d2f350b4c24ee26e33daea5f08d58ef","versionType":"git"},{"version":"448325199f574d33824dbf9121efb03558412966","status":"affected","lessThan":"7cf9cd98cf6f0df3befc167ca6b54c07014d71de","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/bpf.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.1","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.52","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/bpf.h"]}],"references":["https://git.kernel.org/stable/c/e0653c8f718109d140e806daac166c43e2b2b8bd","https://git.kernel.org/stable/c/953e85da53541a8dc3e7ad4e8532f29a34a32eae","https://git.kernel.org/stable/c/003bf840ed3326bd01396ce7d5b431cef0d371e7","https://git.kernel.org/stable/c/5e9f69829835521aa2942d1d14bd0990fbc6991e","https://git.kernel.org/stable/c/ff3f22ed8d2f350b4c24ee26e33daea5f08d58ef","https://git.kernel.org/stable/c/7cf9cd98cf6f0df3befc167ca6b54c07014d71de"],"weaknesses":[],"ingestedAt":"2026-10-30T12:56:04.490Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/93xxx/CVE-2026-93174.json","commit":"1f312381e38164a43607eebab851b151dd16861e","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-93174","state":"PUBLISHED","datePublished":"2026-09-17T16:12:03.946Z","dateUpdated":"2026-10-30T12:36:14.183Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-17T16:02:15.090Z"},"containers":{"cna":{"title":"bpf: Copy per-CPU map value padding in copy_map_value_long()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Copy per-CPU map value padding in copy_map_value_long()\n\nIn kernel, per-CPU map elements are stored with\nround_up(map->value_size, 8) bytes. On UAPI lookup paths, it copies the\nrounded size for each CPU into a temporary buffer.\n\nHowever, copy_map_value_long() passes 'map->value_size' to\nbpf_obj_memcpy(). When the map has special fields, bpf_obj_memcpy() copies\naround those fields with memcpy(), and does not copy the tail padding\nbetween 'map->value_size' and round_up(map->value_size, 8).\n\nThe temporary UAPI lookup buffers are allocated without __GFP_ZERO. As a\nresult, when the per-CPU map's value size is not equal to\nround_up(map->value_size, 8), UAPI LOOKUP_ELEM and its variants can return\nstale heap contents from that padding to user space. The same issue\napplies to bpf_iter for per-CPU maps.\n\nPass round_up(map->value_size, 8) to bpf_obj_memcpy() from\ncopy_map_value_long(), so per-CPU maps both with and without special\nfields copy the entire per-CPU slot. Remove the now redundant round_up()\nfrom bpf_obj_memcpy()'s long_memcpy path."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"448325199f574d33824dbf9121efb03558412966","status":"affected","lessThan":"e0653c8f718109d140e806daac166c43e2b2b8bd","versionType":"git"},{"version":"448325199f574d33824dbf9121efb03558412966","status":"affected","lessThan":"953e85da53541a8dc3e7ad4e8532f29a34a32eae","versionType":"git"},{"version":"448325199f574d33824dbf9121efb03558412966","status":"affected","lessThan":"003bf840ed3326bd01396ce7d5b431cef0d371e7","versionType":"git"},{"version":"448325199f574d33824dbf9121efb03558412966","status":"affected","lessThan":"5e9f69829835521aa2942d1d14bd0990fbc6991e","versionType":"git"},{"version":"448325199f574d33824dbf9121efb03558412966","status":"affected","lessThan":"ff3f22ed8d2f350b4c24ee26e33daea5f08d58ef","versionType":"git"},{"version":"448325199f574d33824dbf9121efb03558412966","status":"affected","lessThan":"7cf9cd98cf6f0df3befc167ca6b54c07014d71de","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/bpf.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.1","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.52","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/bpf.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/e0653c8f718109d140e806daac166c43e2b2b8bd"},{"url":"https://git.kernel.org/stable/c/953e85da53541a8dc3e7ad4e8532f29a34a32eae"},{"url":"https://git.kernel.org/stable/c/003bf840ed3326bd01396ce7d5b431cef0d371e7"},{"url":"https://git.kernel.org/stable/c/5e9f69829835521aa2942d1d14bd0990fbc6991e"},{"url":"https://git.kernel.org/stable/c/ff3f22ed8d2f350b4c24ee26e33daea5f08d58ef"},{"url":"https://git.kernel.org/stable/c/7cf9cd98cf6f0df3befc167ca6b54c07014d71de"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:36:14.183Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.18.52"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}