{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2024-39510",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "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."
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "Linux",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Linux",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "<",
                                            "version_name": "f17443d52d80",
                                            "version_value": "cb55625f8eb9"
                                        },
                                        {
                                            "version_affected": "<",
                                            "version_name": "f740fd943bb1",
                                            "version_value": "3958679c4915"
                                        },
                                        {
                                            "version_affected": "<",
                                            "version_name": "0a7e54c1959c",
                                            "version_value": "93064676a282"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "6.8",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "6.8",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.9.6",
                                                        "lessThanOrEqual": "6.9.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.10",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/cb55625f8eb9d2de8be4da0c4580d48cbb32058e",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/cb55625f8eb9d2de8be4da0c4580d48cbb32058e"
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                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/3958679c49152391209b32be3357193300a51abd"
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            {
                "url": "https://git.kernel.org/stable/c/93064676a2820420a2d37d7c8289f277fe20793d",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/93064676a2820420a2d37d7c8289f277fe20793d"
            },
            {
                "url": "https://git.kernel.org/stable/c/da4a827416066191aafeeccee50a8836a826ba10",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/da4a827416066191aafeeccee50a8836a826ba10"
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        ]
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    "generator": {
        "engine": "bippy-c9c4e1df01b2"
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}