CVE-2023-53256
Vulnérabilité moyenne dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: firmware: arm_ffa: Fix FFA device names for logical partitions Each physical partition can provide multiple services each with UUID. Each such service can be presented as logical partition with a unique combination of VM ID and UUID. The number of distinct UUID in a system will be less than or equal to the number of logical partitions. However, currently it fails to register more than one logical partition or service within a physical partition as the device name contains only VM ID while both VM ID and UUID are maintained in the partition information. The kernel complains with the below message: | sysfs: cannot create duplicate filename '/devices/arm-ffa-8001' | CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.3.0-rc7 #8 | Hardware name: FVP Base RevC (DT) | Call trace: | dump_backtrace+0xf8/0x118 | show_stack+0x18/0x24 | dump_stack_lvl+0x50/0x68 | dump_stack+0x18/0x24 | sysfs_create_dir_ns+0xe0/0x13c | kobject_add_internal+0x220/0x3d4 | kobject_add+0x94/0x100 | device_add+0x144/0x5d8 | device_register+0x20/0x30 | ffa_device_register+0x88/0xd8 | ffa_setup_partitions+0x108/0x1b8 | ffa_init+0x2ec/0x3a4 | do_one_initcall+0xcc/0x240 | do_initcall_level+0x8c/0xac | do_initcalls+0x54/0x94 | do_basic_setup+0x1c/0x28 | kernel_init_freeable+0x100/0x16c | kernel_init+0x20/0x1a0 | ret_from_fork+0x10/0x20 | kobject_add_internal failed for arm-ffa-8001 with -EEXIST, don't try to | register things with the same name in the same directory. | arm_ffa arm-ffa: unable to register device arm-ffa-8001 err=-17 | ARM FF-A: ffa_setup_partitions: failed to register partition ID 0x8001 By virtue of being random enough to avoid collisions when generated in a distributed system, there is no way to compress UUID keys to the number of bits required to identify each. We can eliminate '-' in the name but it is not worth eliminating 4 bytes and add unnecessary logic for doing that. Also v1.0 doesn't provide the UUID of the partitions which makes it hard to use the same for the device name. So to keep it simple, let us alloc an ID using ida_alloc() and append the same to "arm-ffa" to make up a unique device name. Also stash the id value in ffa_dev to help freeing the ID later when the device is destroyed.
Gravité et risque d'exploitation
CVE-2023-53256 obtient un score CVSS de 5.5/10, soit une gravité moyenne. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.15 %, ce qui la place devant 3.7 % des CVE référencées.
Que faire ?
- Vérifiez si Linux (versions <=6.3.*, <=6.1.*, <5.14, 6.4, <=*, e781858488b918e30a6ff28e9eab6058b787e3b3, <=5.15.*, 6.3.5, <93d0cbe88118fcef234d3ebcbdadcb9ebe9d34f1, <dfc5aaa57f52a5800c339369d235fa30fb734feb, <19b8766459c41c6f318f8a548cc1c66dffd18363, 5.14, 0, 5.15.114, <c2f65991097a62efbdb2bed3c06fc86b08c9593b, 6.1.31) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.