CVE-2024-26695 crypto: ccp - Fix null pointer dereference in __sev_platform_shutdown_locked
A null pointer dereference in the Linux kernel's CCP driver can cause a system crash when the SEV platform is shut down with a null master pointer.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-26695?
CVE-2024-26695 is a medium-severity vulnerability in Debian Debian Linux, published on 3 Apr 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
crypto: ccp - Fix null pointer dereference in __sev_platform_shutdown_locked
The SEV platform device can be shutdown with a null psp_master, e.g., using DEBUG_TEST_DRIVER_REMOVE. Found using KASAN:
[ 137.148210] ccp 0000:23:00.1: enabling device (0000 -> 0002) [ 137.162647] ccp 0000:23:00.1: no command queues available [ 137.170598] ccp 0000:23:00.1: sev enabled [ 137.174645] ccp 0000:23:00.1: psp enabled [ 137.178890] general protection fault, probably for non-canonical address 0xdffffc000000001e: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN NOPTI [ 137.182693] KASAN: null-ptr-deref in range [0x00000000000000f0-0x00000000000000f7] [ 137.182693] CPU: 93 PID: 1 Comm: swapper/0 Not tainted 6.8.0-rc1+ #311 [ 137.182693] RIP: 0010:__sev_platform_shutdown_locked+0x51/0x180 [ 137.182693] Code: 08 80 3c 08 00 0f 85 0e 01 00 00 48 8b 1d 67 b6 01 08 48 b8 00 00 00 00 00 fc ff df 48 8d bb f0 00 00 00 48 89 f9 48 c1 e9 03 <80> 3c 01 00 0f 85 fe 00 00 00 48 8b 9b f0 00 00 00 48 85 db 74 2c [ 137.182693] RSP: 0018:ffffc900000cf9b0 EFLAGS: 00010216 [ 137.182693] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 000000000000001e [ 137.182693] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 00000000000000f0 [ 137.182693] RBP: ffffc900000cf9c8 R08: 0000000000000000 R09: fffffbfff58f5a66 [ 137.182693] R10: ffffc900000cf9c8 R11: ffffffffac7ad32f R12: ffff8881e5052c28 [ 137.182693] R13: ffff8881e5052c28 R14: ffff8881758e43e8 R15: ffffffffac64abf8 [ 137.182693] FS: 0000000000000000(0000) GS:ffff889de7000000(0000) knlGS:0000000000000000 [ 137.182693] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 137.182693] CR2: 0000000000000000 CR3: 0000001cf7c7e000 CR4: 0000000000350ef0 [ 137.182693] Call Trace: [ 137.182693] <TASK> [ 137.182693] ? show_regs+0x6c/0x80 [ 137.182693] ? __die_body+0x24/0x70 [ 137.182693] ? die_addr+0x4b/0x80 [ 137.182693] ? exc_general_protection+0x126/0x230 [ 137.182693] ? asm_exc_general_protection+0x2b/0x30 [ 137.182693] ? __sev_platform_shutdown_locked+0x51/0x180 [ 137.182693] sev_firmware_shutdown.isra.0+0x1e/0x80 [ 137.182693] sev_dev_destroy+0x49/0x100 [ 137.182693] psp_dev_destroy+0x47/0xb0 [ 137.182693] sp_destroy+0xbb/0x240 [ 137.182693] sp_pci_remove+0x45/0x60 [ 137.182693] pci_device_remove+0xaa/0x1d0 [ 137.182693] device_remove+0xc7/0x170 [ 137.182693] really_probe+0x374/0xbe0 [ 137.182693] ? srso_return_thunk+0x5/0x5f [ 137.182693] __driver_probe_device+0x199/0x460 [ 137.182693] driver_probe_device+0x4e/0xd0 [ 137.182693] __driver_attach+0x191/0x3d0 [ 137.182693] ? __pfx___driver_attach+0x10/0x10 [ 137.182693] bus_for_each_dev+0x100/0x190 [ 137.182693] ? __pfx_bus_for_each_dev+0x10/0x10 [ 137.182693] ? __kasan_check_read+0x15/0x20 [ 137.182693] ? srso_return_thunk+0x5/0x5f [ 137.182693] ? _raw_spin_unlock+0x27/0x50 [ 137.182693] driver_attach+0x41/0x60 [ 137.182693] bus_add_driver+0x2a8/0x580 [ 137.182693] driver_register+0x141/0x480 [ 137.182693] __pci_register_driver+0x1d6/0x2a0 [ 137.182693] ? srso_return_thunk+0x5/0x5f [ 137.182693] ? esrt_sysfs_init+0x1cd/0x5d0 [ 137.182693] ? __pfx_sp_mod_init+0x10/0x10 [ 137.182693] sp_pci_init+0x22/0x30 [ 137.182693] sp_mod_init+0x14/0x30 [ 137.182693] ? __pfx_sp_mod_init+0x10/0x10 [ 137.182693] do_one_initcall+0xd1/0x470 [ 137.182693] ? __pfx_do_one_initcall+0x10/0x10 [ 137.182693] ? parameq+0x80/0xf0 [ 137.182693] ? srso_return_thunk+0x5/0x5f [ 137.182693] ? __kmalloc+0x3b0/0x4e0 [ 137.182693] ? kernel_init_freeable+0x92d/0x1050 [ 137.182693] ? kasan_populate_vmalloc_pte+0x171/0x190 [ 137.182693] ? srso_return_thunk+0x5/0x5f [ 137.182693] kernel_init_freeable+0xa64/0x1050 [ 137.182693] ? __pfx_kernel_init+0x10/0x10 [ 137.182693] kernel_init+0x24/0x160 [ 137.182693] ? __switch_to_asm+0x3e/0x70 [ 137.182693] ret_from_fork+0x40/0x80 [ 137.182693] ? __pfx_kernel_init+0x1 ---truncated---
Weakness: CWE-476
Which versions are affected by CVE-2024-26695?
It affects 2 products.
Products include Debian Debian Linux, Linux kernel.
How do I fix CVE-2024-26695?
Apply the vendor's patch.
Is CVE-2024-26695 being exploited?
There is no known exploitation of CVE-2024-26695 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as BELL-CVE-2024-26695, DEBIAN-CVE-2024-26695, GHSA-2mrh-g8f4-xvjv, UBUNTU-CVE-2024-26695.