{"cve":"CVE-2024-39510","nvd":{"published":"2024-07-12T13:15:13.283","modified":"2026-06-17T07:42:04.727","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncachefiles: fix slab-use-after-free in cachefiles_ondemand_daemon_read()\n\nWe got the following issue in a fuzz test of randomly issuing the restore\ncommand:\n\n==================================================================\nBUG: KASAN: slab-use-after-free in cachefiles_ondemand_daemon_read+0xb41/0xb60\nRead of size 8 at addr ffff888122e84088 by task ondemand-04-dae/963\n\nCPU: 13 PID: 963 Comm: ondemand-04-dae Not tainted 6.8.0-dirty #564\nCall Trace:\n kasan_report+0x93/0xc0\n cachefiles_ondemand_daemon_read+0xb41/0xb60\n vfs_read+0x169/0xb50\n ksys_read+0xf5/0x1e0\n\nAllocated by task 116:\n kmem_cache_alloc+0x140/0x3a0\n cachefiles_lookup_cookie+0x140/0xcd0\n fscache_cookie_state_machine+0x43c/0x1230\n [...]\n\nFreed by task 792:\n kmem_cache_free+0xfe/0x390\n cachefiles_put_object+0x241/0x480\n fscache_cookie_state_machine+0x5c8/0x1230\n [...]\n==================================================================\n\nFollowing is the process that triggers the issue:\n\n     mount  |   daemon_thread1    |    daemon_thread2\n------------------------------------------------------------\ncachefiles_withdraw_cookie\n cachefiles_ondemand_clean_object(object)\n  cachefiles_ondemand_send_req\n   REQ_A = kzalloc(sizeof(*req) + data_len)\n   wait_for_completion(&REQ_A->done)\n\n            cachefiles_daemon_read\n             cachefiles_ondemand_daemon_read\n              REQ_A = cachefiles_ondemand_select_req\n              msg->object_id = req->object->ondemand->ondemand_id\n                                  ------ restore ------\n                                  cachefiles_ondemand_restore\n                                  xas_for_each(&xas, req, ULONG_MAX)\n                                   xas_set_mark(&xas, CACHEFILES_REQ_NEW)\n\n                                  cachefiles_daemon_read\n                                   cachefiles_ondemand_daemon_read\n                                    REQ_A = cachefiles_ondemand_select_req\n              copy_to_user(_buffer, msg, n)\n               xa_erase(&cache->reqs, id)\n               complete(&REQ_A->done)\n              ------ close(fd) ------\n              cachefiles_ondemand_fd_release\n               cachefiles_put_object\n cachefiles_put_object\n  kmem_cache_free(cachefiles_object_jar, object)\n                                    REQ_A->object->ondemand->ondemand_id\n                                     // object UAF !!!\n\nWhen we see the request within xa_lock, req->object must not have been\nfreed yet, so grab the reference count of object before xa_unlock to\navoid the above issue.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-416"],"references":["https://git.kernel.org/stable/c/3958679c49152391209b32be3357193300a51abd","https://git.kernel.org/stable/c/93064676a2820420a2d37d7c8289f277fe20793d","https://git.kernel.org/stable/c/cb55625f8eb9d2de8be4da0c4580d48cbb32058e","https://git.kernel.org/stable/c/da4a827416066191aafeeccee50a8836a826ba10","https://git.kernel.org/stable/c/3958679c49152391209b32be3357193300a51abd"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:52:42.518321223+00:00"},"epss":{"cve":"CVE-2024-39510","score":0.00284,"percentile":0.20925,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}