{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2023-54165", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-12-30T12:06:44.495Z", "datePublished": "2025-12-30T12:08:41.019Z", "dateUpdated": "2026-08-05T09:17:46.890Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T09:17:46.890Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nzsmalloc: move LRU update from zs_map_object() to zs_malloc()\n\nUnder memory pressure, we sometimes observe the following crash:\n\n[ 5694.832838] ------------[ cut here ]------------\n[ 5694.842093] list_del corruption, ffff888014b6a448->next is LIST_POISON1 (dead000000000100)\n[ 5694.858677] WARNING: CPU: 33 PID: 418824 at lib/list_debug.c:47 __list_del_entry_valid+0x42/0x80\n[ 5694.961820] CPU: 33 PID: 418824 Comm: fuse_counters.s Kdump: loaded Tainted: G S 5.19.0-0_fbk3_rc3_hoangnhatpzsdynshrv41_10870_g85a9558a25de #1\n[ 5694.990194] Hardware name: Wiwynn Twin Lakes MP/Twin Lakes Passive MP, BIOS YMM16 05/24/2021\n[ 5695.007072] RIP: 0010:__list_del_entry_valid+0x42/0x80\n[ 5695.017351] Code: 08 48 83 c2 22 48 39 d0 74 24 48 8b 10 48 39 f2 75 2c 48 8b 51 08 b0 01 48 39 f2 75 34 c3 48 c7 c7 55 d7 78 82 e8 4e 45 3b 00 <0f> 0b eb 31 48 c7 c7 27 a8 70 82 e8 3e 45 3b 00 0f 0b eb 21 48 c7\n[ 5695.054919] RSP: 0018:ffffc90027aef4f0 EFLAGS: 00010246\n[ 5695.065366] RAX: 41fe484987275300 RBX: ffff888008988180 RCX: 0000000000000000\n[ 5695.079636] RDX: ffff88886006c280 RSI: ffff888860060480 RDI: ffff888860060480\n[ 5695.093904] RBP: 0000000000000002 R08: 0000000000000000 R09: ffffc90027aef370\n[ 5695.108175] R10: 0000000000000000 R11: ffffffff82fdf1c0 R12: 0000000010000002\n[ 5695.122447] R13: ffff888014b6a448 R14: ffff888014b6a420 R15: 00000000138dc240\n[ 5695.136717] FS: 00007f23a7d3f740(0000) GS:ffff888860040000(0000) knlGS:0000000000000000\n[ 5695.152899] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 5695.164388] CR2: 0000560ceaab6ac0 CR3: 000000001c06c001 CR4: 00000000007706e0\n[ 5695.178659] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n[ 5695.192927] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n[ 5695.207197] PKRU: 55555554\n[ 5695.212602] Call Trace:\n[ 5695.217486] \n[ 5695.221674] zs_map_object+0x91/0x270\n[ 5695.229000] zswap_frontswap_store+0x33d/0x870\n[ 5695.237885] ? do_raw_spin_lock+0x5d/0xa0\n[ 5695.245899] __frontswap_store+0x51/0xb0\n[ 5695.253742] swap_writepage+0x3c/0x60\n[ 5695.261063] shrink_page_list+0x738/0x1230\n[ 5695.269255] shrink_lruvec+0x5ec/0xcd0\n[ 5695.276749] ? shrink_slab+0x187/0x5f0\n[ 5695.284240] ? mem_cgroup_iter+0x6e/0x120\n[ 5695.292255] shrink_node+0x293/0x7b0\n[ 5695.299402] do_try_to_free_pages+0xea/0x550\n[ 5695.307940] try_to_free_pages+0x19a/0x490\n[ 5695.316126] __folio_alloc+0x19ff/0x3e40\n[ 5695.323971] ? __filemap_get_folio+0x8a/0x4e0\n[ 5695.332681] ? walk_component+0x2a8/0xb50\n[ 5695.340697] ? generic_permission+0xda/0x2a0\n[ 5695.349231] ? __filemap_get_folio+0x8a/0x4e0\n[ 5695.357940] ? walk_component+0x2a8/0xb50\n[ 5695.365955] vma_alloc_folio+0x10e/0x570\n[ 5695.373796] ? walk_component+0x52/0xb50\n[ 5695.381634] wp_page_copy+0x38c/0xc10\n[ 5695.388953] ? filename_lookup+0x378/0xbc0\n[ 5695.397140] handle_mm_fault+0x87f/0x1800\n[ 5695.405157] do_user_addr_fault+0x1bd/0x570\n[ 5695.413520] exc_page_fault+0x5d/0x110\n[ 5695.421017] asm_exc_page_fault+0x22/0x30\n\nAfter some investigation, I have found the following issue: unlike other\nzswap backends, zsmalloc performs the LRU list update at the object\nmapping time, rather than when the slot for the object is allocated.\nThis deviation was discussed and agreed upon during the review process\nof the zsmalloc writeback patch series:\n\nhttps://lore.kernel.org/lkml/Y3flcAXNxxrvy3ZH@cmpxchg.org/\n\nUnfortunately, this introduces a subtle bug that occurs when there is a\nconcurrent store and reclaim, which interleave as follows:\n\nzswap_frontswap_store() shrink_worker()\n zs_malloc() zs_zpool_shrink()\n spin_lock(&pool->lock) zs_reclaim_page()\n zspage = find_get_zspage()\n spin_unlock(&pool->lock)\n spin_lock(&pool->lock)\n zspage = list_first_entry(&pool->lru)\n \n---truncated---" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The race is in the mm swap/zswap store and writeback paths, reached by a local process allocating and dirtying anonymous memory to drive swap-out and pool reclaim. There is no network-facing entry point.\nAC:L - The attacker controls both sides of the race — spawning threads that force zswap stores while holding the pool at its limit so shrink_worker runs concurrently — and can retry at swap-out rates indefinitely, so success depends on nothing outside the attacker's influence.\nPR:L - Only an ordinary unprivileged local user is needed; no capability, namespace, or configuration privilege is required, just memory allocation sufficient to induce swap and zswap pool pressure.\nUI:N - The attacker's own memory pressure triggers both the store and the reclaim worker; no victim action of any kind is needed.\nS:U - The corruption stays within kernel memory managed by the same security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The freed-while-linked zspage yields a use-after-free read on a slab object the attacker can spray, and the raced eviction reads an uninitialized zswap_header, producing an unbounded `zswap_trees[swp_type()]` out-of-bounds read plus write-back/serving of stale compressed data belonging to other processes.\nI:H - List-node corruption and the dangling `pool->lru` entry turn a later `list_del()` on a recycled, attacker-controlled `struct zspage` into an arbitrary unlink write primitive, and writeback of a garbage swpentry can overwrite another process's swap slot.\nA:H - The documented outcome is list_del corruption; without CONFIG_DEBUG_LIST it writes to LIST_POISON addresses and oopses with `pool->lock` held, deadlocking all further zsmalloc/zswap activity and hanging the machine under memory pressure." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "mm/zsmalloc.c" ], "versions": [ { "version": "64f768c6b32e1957e2b65b70e97cb4cb62344bc4", "lessThan": "e95adf7486f2cb5f1bb303113ca30460951923e9", "status": "affected", "versionType": "git" }, { "version": "64f768c6b32e1957e2b65b70e97cb4cb62344bc4", "lessThan": "d461aac924b937bcb4fd0ca1242b3ef6868ecddd", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "mm/zsmalloc.c" ], "versions": [ { "version": "6.2", "status": "affected" }, { "version": "0", "lessThan": "6.2", "status": "unaffected", "versionType": "semver" }, { "version": "6.3.5", "lessThanOrEqual": "6.3.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.4", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.3.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.4" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/e95adf7486f2cb5f1bb303113ca30460951923e9" }, { "url": "https://git.kernel.org/stable/c/d461aac924b937bcb4fd0ca1242b3ef6868ecddd" } ], "title": "zsmalloc: move LRU update from zs_map_object() to zs_malloc()", "x_generator": { "engine": "bippy-1.2.0" } } } }