{"id":"CVE-2026-97583","published":"2026-09-25T11:17:09.127","lastModified":"2026-09-25T15:18:00.290","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nafs: Clear stale peer app data after address list changes\n\nafs_fs_probe_fileserver() fetches the current endpoint state under\nserver->fs_lock, but leaves old_alist as NULL.  Consequently,\nafs_set_peer_appdata() treats every address list replacement as initial\nsetup and only binds the new peers; it never unbinds peers removed from\nthe old list.\n\nAn address refresh can therefore proceed as follows.  CPU 0 replaces\nserver S's list and drops Pold without clearing Pold->app_data.  The\nserver destroyer then clears only S's current peers and lets S reach its\nRCU callback.  After the callback frees S, CPU 1 handles a callback\nthrough an RxRPC connection that still pins Pold, reads Pold->app_data,\nand calls afs_use_server() on the freed object.\n\nKASAN reported:\n\n  BUG: KASAN: slab-use-after-free in afs_find_server+0x3c/0xa0\n  Read of size 4 at addr ffff8881013e1af0 by task krxrpcio/7001/74\n  Call Trace:\n   afs_find_server+0x3c/0xa0\n   afs_rx_new_call+0x15c/0x390\n   rxrpc_new_incoming_call+0x97c/0x1730\n   rxrpc_input_packet.constprop.0+0xd03/0xec0\n   rxrpc_io_thread+0x967/0x1640\n  Allocated by task 93:\n   afs_lookup_server+0x1a7/0x14c0\n   afs_alloc_server_list+0x43f/0xb60\n   afs_create_volume+0x923/0x1490\n   afs_get_tree+0x1c6/0x10a0\n  Freed by task 0:\n   kfree+0x131/0x3c0\n   rcu_core+0x50a/0x1850\n  Last potentially related work creation:\n   __call_rcu_common.constprop.0+0x71/0xa10\n   afs_put_server+0x213/0x2b0\n\nPreserve old->addresses for the peer app-data update so that removed\npeers are cleared before the endpoint state is replaced.  Also advance\nboth cursors when the old and new lists share a peer; activating the\nold/new comparison without this would otherwise loop forever on the\nshared entry.","cvssScore":7.5,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H","cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/3afb988fd0411707bdafb9b321086fff0da28aae","tags":[]},{"url":"https://git.kernel.org/stable/c/7f7f5589d048821dea316cbac9b37d27eaf7530e","tags":[]},{"url":"https://git.kernel.org/stable/c/ba0623fc19a424f4745394c499f9f28a8d88d397","tags":[]},{"url":"https://git.kernel.org/stable/c/c7f77a11a1e719192c7262aad38a3919aec62c21","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}