{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-38517", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T04:51:24.023Z", "datePublished": "2025-08-16T10:55:04.217Z", "dateUpdated": "2026-05-11T21:29:33.070Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-11T21:29:33.070Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nlib/alloc_tag: do not acquire non-existent lock in alloc_tag_top_users()\n\nalloc_tag_top_users() attempts to lock alloc_tag_cttype->mod_lock even\nwhen the alloc_tag_cttype is not allocated because:\n\n 1) alloc tagging is disabled because mem profiling is disabled\n (!alloc_tag_cttype)\n 2) alloc tagging is enabled, but not yet initialized (!alloc_tag_cttype)\n 3) alloc tagging is enabled, but failed initialization\n (!alloc_tag_cttype or IS_ERR(alloc_tag_cttype))\n\nIn all cases, alloc_tag_cttype is not allocated, and therefore\nalloc_tag_top_users() should not attempt to acquire the semaphore.\n\nThis leads to a crash on memory allocation failure by attempting to\nacquire a non-existent semaphore:\n\n Oops: general protection fault, probably for non-canonical address 0xdffffc000000001b: 0000 [#3] SMP KASAN NOPTI\n KASAN: null-ptr-deref in range [0x00000000000000d8-0x00000000000000df]\n CPU: 2 UID: 0 PID: 1 Comm: systemd Tainted: G D 6.16.0-rc2 #1 VOLUNTARY\n Tainted: [D]=DIE\n Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014\n RIP: 0010:down_read_trylock+0xaa/0x3b0\n Code: d0 7c 08 84 d2 0f 85 a0 02 00 00 8b 0d df 31 dd 04 85 c9 75 29 48 b8 00 00 00 00 00 fc ff df 48 8d 6b 68 48 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 88 02 00 00 48 3b 5b 68 0f 85 53 01 00 00 65 ff\n RSP: 0000:ffff8881002ce9b8 EFLAGS: 00010016\n RAX: dffffc0000000000 RBX: 0000000000000070 RCX: 0000000000000000\n RDX: 000000000000001b RSI: 000000000000000a RDI: 0000000000000070\n RBP: 00000000000000d8 R08: 0000000000000001 R09: ffffed107dde49d1\n R10: ffff8883eef24e8b R11: ffff8881002cec20 R12: 1ffff11020059d37\n R13: 00000000003fff7b R14: ffff8881002cec20 R15: dffffc0000000000\n FS: 00007f963f21d940(0000) GS:ffff888458ca6000(0000) knlGS:0000000000000000\n CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007f963f5edf71 CR3: 000000010672c000 CR4: 0000000000350ef0\n Call Trace:\n \n codetag_trylock_module_list+0xd/0x20\n alloc_tag_top_users+0x369/0x4b0\n __show_mem+0x1cd/0x6e0\n warn_alloc+0x2b1/0x390\n __alloc_frozen_pages_noprof+0x12b9/0x21a0\n alloc_pages_mpol+0x135/0x3e0\n alloc_slab_page+0x82/0xe0\n new_slab+0x212/0x240\n ___slab_alloc+0x82a/0xe00\n \n\nAs David Wang points out, this issue became easier to trigger after commit\n780138b12381 (\"alloc_tag: check mem_profiling_support in alloc_tag_init\").\n\nBefore the commit, the issue occurred only when it failed to allocate and\ninitialize alloc_tag_cttype or if a memory allocation fails before\nalloc_tag_init() is called. After the commit, it can be easily triggered\nwhen memory profiling is compiled but disabled at boot.\n\nTo properly determine whether alloc_tag_init() has been called and its\ndata structures initialized, verify that alloc_tag_cttype is a valid\npointer before acquiring the semaphore. If the variable is NULL or an\nerror value, it has not been properly initialized. In such a case, just\nskip and do not attempt to acquire the semaphore.\n\n[harry.yoo@oracle.com: v3]" } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "lib/alloc_tag.c" ], "versions": [ { "version": "1438d349d16b78d88f9e978a4a5496f078c8191b", "lessThan": "febc0b5dbabda414565bdfaaaa59d26f787d5fe7", "status": "affected", "versionType": "git" }, { "version": "1438d349d16b78d88f9e978a4a5496f078c8191b", "lessThan": "22bf79c0c2301b6e15a688220284b147774d277e", "status": "affected", "versionType": "git" }, { "version": "1438d349d16b78d88f9e978a4a5496f078c8191b", "lessThan": "99af22cd34688cc0d535a1919e0bea4cbc6c1ea1", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "lib/alloc_tag.c" ], "versions": [ { "version": "6.10", "status": "affected" }, { "version": "0", "lessThan": "6.10", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.39", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.15.7", "lessThanOrEqual": "6.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.16", "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": "6.10", "versionEndExcluding": "6.12.39" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "6.15.7" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "6.16" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/febc0b5dbabda414565bdfaaaa59d26f787d5fe7" }, { "url": "https://git.kernel.org/stable/c/22bf79c0c2301b6e15a688220284b147774d277e" }, { "url": "https://git.kernel.org/stable/c/99af22cd34688cc0d535a1919e0bea4cbc6c1ea1" } ], "title": "lib/alloc_tag: do not acquire non-existent lock in alloc_tag_top_users()", "x_generator": { "engine": "bippy-1.2.0" } } } }