{"id":"CVE-2026-64067","summary":"netfs: Fix missing barriers when accessing stream-\u003esubrequests locklessly","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfs: Fix missing barriers when accessing stream-\u003esubrequests locklessly\n\nThe list of subrequests attached to stream-\u003esubrequests is accessed without\nlocks by netfs_collect_read_results() and netfs_collect_write_results(),\nand then they access subreq-\u003eflags without taking a barrier after getting\nthe subreq pointer from the list.  Relatedly, the functions that build the\nlist don't use any sort of write barrier when constructing the list to make\nsure that the NETFS_SREQ_IN_PROGRESS flag is perceived to be set first if\nno lock is taken.\n\nFix this by:\n\n (1) Add a new list_add_tail_release() function that uses a release barrier\n     to set the pointer to the new member of the list.\n\n (2) Add a new list_first_entry_or_null_acquire() function that uses an\n     acquire barrier to read the pointer to the first member in a list (or\n     return NULL).\n\n (3) Use list_add_tail_release() when adding a subreq to -\u003esubrequests.\n\n (4) Use list_first_entry_or_null_acquire() when initially accessing the\n     front of the list (when an item is removed, the pointer to the new\n     front iterm is obtained under the same lock).","modified":"2026-07-22T05:29:39.698915573Z","published":"2026-07-19T15:39:44.660Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64067.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/293a4532c36f38458e38b8879b174ab797718b9d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b5782e2d462c028096f922abca46318cec890670"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64067.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64067"},{"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":"288ace2f57c9d06dd2e42bd80d03747d879a4068"},{"fixed":"293a4532c36f38458e38b8879b174ab797718b9d"},{"fixed":"b5782e2d462c028096f922abca46318cec890670"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64067.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.10.0"},{"fixed":"7.0.11"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64067.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}