{"id":"CVE-2026-31438","summary":"netfs: Fix kernel BUG in netfs_limit_iter() for ITER_KVEC iterators","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfs: Fix kernel BUG in netfs_limit_iter() for ITER_KVEC iterators\n\nWhen a process crashes and the kernel writes a core dump to a 9P\nfilesystem, __kernel_write() creates an ITER_KVEC iterator. This\niterator reaches netfs_limit_iter() via netfs_unbuffered_write(), which\nonly handles ITER_FOLIOQ, ITER_BVEC and ITER_XARRAY iterator types,\nhitting the BUG() for any other type.\n\nFix this by adding netfs_limit_kvec() following the same pattern as\nnetfs_limit_bvec(), since both kvec and bvec are simple segment arrays\nwith pointer and length fields. Dispatch it from netfs_limit_iter() when\nthe iterator type is ITER_KVEC.","modified":"2026-07-15T01:49:16.408342091Z","published":"2026-04-22T13:53:37.053Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31438.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/00d6df7115f6972370974212de9088087820802e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/18c2e20b42dd21db599e42d05ddaeeb647b2bb6d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4bc2d72c7695cedf6d4e1a558924903c2b28a78e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/67e467a11f62ff64ad219dc6aa5459e132c79d14"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31438.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31438"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"cae932d3aee55035a54415dcea8e7ecf2ec469b5"},{"fixed":"18c2e20b42dd21db599e42d05ddaeeb647b2bb6d"},{"fixed":"4bc2d72c7695cedf6d4e1a558924903c2b28a78e"},{"fixed":"00d6df7115f6972370974212de9088087820802e"},{"fixed":"67e467a11f62ff64ad219dc6aa5459e132c79d14"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-31438.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.8.0"},{"fixed":"6.12.80"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.21"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"6.19.11"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-31438.json"}}],"schema_version":"1.7.5"}