CVE-2026-98920
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: netfs: Fix missing alloc tagging of direct mempool allocations Commit 1d78d56c43ef ("netfs: Fix folio_queue ENOMEM in writeback by adding a mempool") added a mempool for the folio_queues and made the request, subrequest and folio_queue allocations distinguish between writeback and everything else. Writeback is part of memory reclaim and must not fail due to ENOMEM, so it allocates under GFP_NOFS through mempool_alloc(), which may dip into the pool's reserve and, if that runs empty, wait for elements to be returned. The GFP_KERNEL paths, which can return -ENOMEM to their callers, invoke the pool's ->alloc() callback directly instead. The direct call, however, skips the alloc_hooks() wrapper that the mempool_alloc() macro provides. The pool callbacks, mempool_alloc_slab() and mempool_kmalloc(), call kmem_cache_alloc_noprof() and kmalloc_noprof() and rely on current->alloc_tag having been set by the caller. With CONFIG_MEM_ALLOC_PROFILING_DEBUG=y this leads to current->alloc_tag not set WARNING: ./include/linux/alloc_tag.h:161 at __alloc_tagging_slab_alloc_hook alloc_tag was not set WARNING: ./include/linux/alloc_tag.h:166 at __alloc_tagging_slab_free_hook at allocation and free time respectively, as reported when reading files on a CIFS mount. The allocations are also missing from /proc/allocinfo. Wrap the direct ->alloc() invocations in alloc_hooks() with a new mempool_alloc_noreserve() helper in include/linux/mempool.h, next to the other alloc_hooks()-wrapped macros such as mempool_alloc(). The GFP_KERNEL paths keep their failable allocation semantics, they just get tagged now.
View original CVE JSON
{
"id": "CVE-2026-98920",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-10-23T13:17:12.617",
"lastModified": "2026-10-23T13:17:12.617",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "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."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"fs/netfs/objects.c",
"fs/netfs/rolling_buffer.c",
"include/linux/mempool.h"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "15ed8a9b7c63e9171f5139a6aaa1ffb61809861f",
"lessThan": "5c03da745171485fd181f17b69213464f6d05f3d",
"versionType": "git",
"status": "affected"
},
{
"version": "1d78d56c43ef3768183e8370e7367b162700e049",
"lessThan": "37a2042748bc880df03ff8315db86ed82991fbb8",
"versionType": "git",
"status": "affected"
},
{
"version": "1d78d56c43ef3768183e8370e7367b162700e049",
"lessThan": "b78b728e21c32ec4c330b299f657fb1eb02dffc2",
"versionType": "git",
"status": "affected"
},
{
"version": "b343252d6f536203dd0660f676190dcbf6d2ecdc",
"versionType": "git",
"status": "affected"
},
{
"version": "3f6d7f8a5416d852648d15a05e895f1195ee8a85",
"versionType": "git",
"status": "affected"
},
{
"version": "6.12.114",
"lessThan": "6.13",
"versionType": "semver",
"status": "affected"
},
{
"version": "7.1.8",
"lessThan": "7.2",
"versionType": "semver",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"fs/netfs/objects.c",
"fs/netfs/rolling_buffer.c",
"include/linux/mempool.h"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "7.2",
"status": "affected"
},
{
"version": "0",
"lessThan": "7.2",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2.9",
"lessThanOrEqual": "7.2.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.3",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {},
"references": [
{
"url": "https://git.kernel.org/stable/c/37a2042748bc880df03ff8315db86ed82991fbb8",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/5c03da745171485fd181f17b69213464f6d05f3d",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/b78b728e21c32ec4c330b299f657fb1eb02dffc2",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}