{"id":"CVE-2026-98920","revision":"be67fa7f1cb84275b2219335cad0424b","records":[{"revision":"be67fa7f1cb84275b2219335cad0424b","observedAt":"2026-10-23T16:01:20.601+00:00","statement":{"source":"cve-program","id":"CVE-2026-98920","aliases":[],"title":"netfs: Fix missing alloc tagging of direct mempool allocations","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfs: Fix missing alloc tagging of direct mempool allocations\n\nCommit 1d78d56c43ef (\"netfs: Fix folio_queue ENOMEM in writeback by\nadding a mempool\") added a mempool for the folio_queues and made the\nrequest, subrequest and folio_queue allocations distinguish between\nwriteback and everything else.  Writeback is part of memory reclaim\nand must not fail due to ENOMEM, so it allocates under GFP_NOFS\nthrough mempool_alloc(), which may dip into the pool's reserve and,\nif that runs empty, wait for elements to be returned.  The\nGFP_KERNEL paths, which can return -ENOMEM to their callers, invoke\nthe pool's ->alloc() callback directly instead.\n\nThe direct call, however, skips the alloc_hooks() wrapper that the\nmempool_alloc() macro provides.  The pool callbacks, mempool_alloc_slab()\nand mempool_kmalloc(), call kmem_cache_alloc_noprof() and kmalloc_noprof()\nand rely on current->alloc_tag having been set by the caller.  With\nCONFIG_MEM_ALLOC_PROFILING_DEBUG=y this leads to\n\n    current->alloc_tag not set\n    WARNING: ./include/linux/alloc_tag.h:161 at __alloc_tagging_slab_alloc_hook\n    alloc_tag was not set\n    WARNING: ./include/linux/alloc_tag.h:166 at __alloc_tagging_slab_free_hook\n\nat allocation and free time respectively, as reported when reading\nfiles on a CIFS mount.  The allocations are also missing from\n/proc/allocinfo.\n\nWrap the direct ->alloc() invocations in alloc_hooks() with a new\nmempool_alloc_noreserve() helper in include/linux/mempool.h, next to\nthe other alloc_hooks()-wrapped macros such as mempool_alloc().  The\nGFP_KERNEL paths keep their failable allocation semantics, they just\nget tagged now.","state":0,"publishedAt":"2026-10-23T12:02:06.56+00:00","modifiedAt":"2026-10-23T12:05:25.919+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/netfs/objects.c\",\n                        \"fs/netfs/rolling_buffer.c\",\n                        \"include/linux/mempool.h\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"15ed8a9b7c63e9171f5139a6aaa1ffb61809861f\",\n                            \"lessThan\": \"5c03da745171485fd181f17b69213464f6d05f3d\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1d78d56c43ef3768183e8370e7367b162700e049\",\n                            \"lessThan\": \"37a2042748bc880df03ff8315db86ed82991fbb8\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1d78d56c43ef3768183e8370e7367b162700e049\",\n                            \"lessThan\": \"b78b728e21c32ec4c330b299f657fb1eb02dffc2\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"b343252d6f536203dd0660f676190dcbf6d2ecdc\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"3f6d7f8a5416d852648d15a05e895f1195ee8a85\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"6.12.114\",\n                            \"lessThan\": \"6.13\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1.8\",\n                            \"lessThan\": \"7.2\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/netfs/objects.c\",\n                        \"fs/netfs/rolling_buffer.c\",\n                        \"include/linux/mempool.h\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"7.2\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"7.2\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.9\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/5c03da745171485fd181f17b69213464f6d05f3d","https://git.kernel.org/stable/c/37a2042748bc880df03ff8315db86ed82991fbb8","https://git.kernel.org/stable/c/b78b728e21c32ec4c330b299f657fb1eb02dffc2"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98920","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98920","identifiers":["CVE-2026-98920"]},"retained":false,"historicalAffected":[]}],"coverage":[]}