In the Linux kernel, the following vulnerability has been resolved: cachefiles: remove requests from xarray during flushing requests Even with CACHEFILES_DEAD set, we can still read the requests, so in the following concurrency the request may be used after it has been freed: mount | daemon_thread1 | daemon_thread2 ------------------------------------------------------------ cachefiles_ondemand_init_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 // close dev fd cachefiles_flush_reqs complete(&REQ_A->done) kfree(REQ_A) xa_lock(&cache->reqs); cachefiles_ondemand_select_req req->msg.opcode != CACHEFILES_OP_READ // req use-after-free !!! xa_unlock(&cache->reqs); xa_destroy(&cache->reqs) Hence remove requests from cache->reqs when flushing them to avoid accessing freed requests.
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
Debian | 12 | all | linux | < 6.1.99-1 | linux_6.1.99-1_all.deb |
Debian | 11 | all | linux | < 5.10.223-1 | linux_5.10.223-1_all.deb |
Debian | 999 | all | linux | < 6.9.7-1 | linux_6.9.7-1_all.deb |
Debian | 13 | all | linux | < 6.9.7-1 | linux_6.9.7-1_all.deb |