cbcvebase.
CVE-2024-39510
published 2024-07-12

CVE-2024-39510: In the Linux kernel, the following vulnerability has been resolved: cachefiles: fix slab-use-after-free in cachefiles_ondemand_daemon_read() We got the…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.28%
20.6th percentile
In the Linux kernel, the following vulnerability has been resolved: cachefiles: fix slab-use-after-free in cachefiles_ondemand_daemon_read() We got the following issue in a fuzz test of randomly issuing the restore command: BUG: KASAN: slab-use-after-free in cachefiles_ondemand_daemon_read+0xb41/0xb60 Read of size 8 at addr ffff888122e84088 by task ondemand-04-dae/963 CPU: 13 PID: 963 Comm: ondemand-04-dae Not tainted 6.8.0-dirty #564 Call Trace: kasan_report+0x93/0xc0 cachefiles_ondemand_daemon_read+0xb41/0xb60 vfs_read+0x169/0xb50 ksys_read+0xf5/0x1e0 Allocated by task 116: kmem_cache_alloc+0x140/0x3a0 cachefiles_lookup_cookie+0x140/0xcd0 fscache_cookie_state_machine+0x43c/0x1230 [...] Freed by task 792: kmem_cache_free+0xfe/0x390 cachefiles_put_object+0x241/0x480 fscache_cookie_state_machine+0x5c8/0x1230 [...] Following is the process that triggers the issue: mount | daemon_thread1 | daemon_thread2 cachefiles_withdraw_cookie cachefiles_ondemand_clean_object(object) cachefiles_ondemand_send_req REQ_A = kzalloc(sizeof(*req) + data_len) wait_for_completion(&REQ_A->done) cachefiles_daemon_read cachefiles_ondemand_daemon_read REQ_A = cachefiles_ondemand_select_req msg->object_id = req->object->ondemand->ondemand_id ------ restore ------ cachefiles_ondemand_restore xas_for_each(&xas, req, ULONG_MAX) xas_set_mark(&xas, CACHEFILES_REQ_NEW) cachefiles_daemon_read cachefiles_ondemand_daemon_read REQ_A = cachefiles_ondemand_select_req copy_to_user(_buffer, msg, n) xa_erase(&cache->reqs, id) complete(&REQ_A->done) ------ close(fd) ------ cachefiles_ondemand_fd_release cachefiles_put_object cachefiles_put_object kmem_cache_free(cachefiles_object_jar, object) REQ_A->object->ondemand->ondemand_id // object UAF !!! When we see the request within xa_lock, req->object must not have been freed yet, so grab the reference count of object before xa_unlock to avoid the above issue.

Affected

13 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.99-1 (bookworm)linux 6.1.99-1 (bookworm)
debianlinux-6.1< linux 6.1.99-1 (bookworm)linux 6.1.99-1 (bookworm)
linuxlinux
linuxlinux>= 0a7e54c1959c0feb2de23397ec09c7692364313e < 93064676a2820420a2d37d7c8289f277fe20793d93064676a2820420a2d37d7c8289f277fe20793d
linuxlinux>= 0a7e54c1959c0feb2de23397ec09c7692364313e < da4a827416066191aafeeccee50a8836a826ba10da4a827416066191aafeeccee50a8836a826ba10
linuxlinux>= f17443d52d805c9a7fab5e67a4e8b973626fe1cd < cb55625f8eb9d2de8be4da0c4580d48cbb32058ecb55625f8eb9d2de8be4da0c4580d48cbb32058e
linuxlinux>= f740fd943bb1fbf79b7eaba3c71eb7536f437f51 < 3958679c49152391209b32be3357193300a51abd3958679c49152391209b32be3357193300a51abd
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.1.99-16.1.99-1
linuxlinux_kernel>= 0 < 6.9.7-16.9.7-1
linuxlinux_kernel>= 0 < 6.9.7-16.9.7-1
linuxlinux_kernel>= 0 < 6.8.0-44.446.8.0-44.44
linuxlinux_kernel>= 6.8 < 6.9.66.9.6

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
vendor_ubuntu5.5MEDIUM
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