| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-35995: ACPI: CPPC: Use access_width over bit_width for system memory accesses |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| ACPI: CPPC: Use access_width over bit_width for system memory accesses |
| |
| To align with ACPI 6.3+, since bit_width can be any 8-bit value, it |
| cannot be depended on to be always on a clean 8b boundary. This was |
| uncovered on the Cobalt 100 platform. |
| |
| SError Interrupt on CPU26, code 0xbe000011 -- SError |
| CPU: 26 PID: 1510 Comm: systemd-udevd Not tainted 5.15.2.1-13 #1 |
| Hardware name: MICROSOFT CORPORATION, BIOS MICROSOFT CORPORATION |
| pstate: 62400009 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--) |
| pc : cppc_get_perf_caps+0xec/0x410 |
| lr : cppc_get_perf_caps+0xe8/0x410 |
| sp : ffff8000155ab730 |
| x29: ffff8000155ab730 x28: ffff0080139d0038 x27: ffff0080139d0078 |
| x26: 0000000000000000 x25: ffff0080139d0058 x24: 00000000ffffffff |
| x23: ffff0080139d0298 x22: ffff0080139d0278 x21: 0000000000000000 |
| x20: ffff00802b251910 x19: ffff0080139d0000 x18: ffffffffffffffff |
| x17: 0000000000000000 x16: ffffdc7e111bad04 x15: ffff00802b251008 |
| x14: ffffffffffffffff x13: ffff013f1fd63300 x12: 0000000000000006 |
| x11: ffffdc7e128f4420 x10: 0000000000000000 x9 : ffffdc7e111badec |
| x8 : ffff00802b251980 x7 : 0000000000000000 x6 : ffff0080139d0028 |
| x5 : 0000000000000000 x4 : ffff0080139d0018 x3 : 00000000ffffffff |
| x2 : 0000000000000008 x1 : ffff8000155ab7a0 x0 : 0000000000000000 |
| Kernel panic - not syncing: Asynchronous SError Interrupt |
| CPU: 26 PID: 1510 Comm: systemd-udevd Not tainted |
| 5.15.2.1-13 #1 |
| Hardware name: MICROSOFT CORPORATION, BIOS MICROSOFT CORPORATION |
| Call trace: |
| dump_backtrace+0x0/0x1e0 |
| show_stack+0x24/0x30 |
| dump_stack_lvl+0x8c/0xb8 |
| dump_stack+0x18/0x34 |
| panic+0x16c/0x384 |
| add_taint+0x0/0xc0 |
| arm64_serror_panic+0x7c/0x90 |
| arm64_is_fatal_ras_serror+0x34/0xa4 |
| do_serror+0x50/0x6c |
| el1h_64_error_handler+0x40/0x74 |
| el1h_64_error+0x7c/0x80 |
| cppc_get_perf_caps+0xec/0x410 |
| cppc_cpufreq_cpu_init+0x74/0x400 [cppc_cpufreq] |
| cpufreq_online+0x2dc/0xa30 |
| cpufreq_add_dev+0xc0/0xd4 |
| subsys_interface_register+0x134/0x14c |
| cpufreq_register_driver+0x1b0/0x354 |
| cppc_cpufreq_init+0x1a8/0x1000 [cppc_cpufreq] |
| do_one_initcall+0x50/0x250 |
| do_init_module+0x60/0x27c |
| load_module+0x2300/0x2570 |
| __do_sys_finit_module+0xa8/0x114 |
| __arm64_sys_finit_module+0x2c/0x3c |
| invoke_syscall+0x78/0x100 |
| el0_svc_common.constprop.0+0x180/0x1a0 |
| do_el0_svc+0x84/0xa0 |
| el0_svc+0x2c/0xc0 |
| el0t_64_sync_handler+0xa4/0x12c |
| el0t_64_sync+0x1a4/0x1a8 |
| |
| Instead, use access_width to determine the size and use the offset and |
| width to shift and mask the bits to read/write out. Make sure to add a |
| check for system memory since pcc redefines the access_width to |
| subspace id. |
| |
| If access_width is not set, then fall back to using bit_width. |
| |
| [ rjw: Subject and changelog edits, comment adjustments ] |
| |
| The Linux kernel CVE team has assigned CVE-2024-35995 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 6.1.90 with commit 01fc53be672acae37e611c80cc0b4f3939584de3 |
| Fixed in 6.6.30 with commit 1b890ae474d19800a6be1696df7fb4d9a41676e4 |
| Fixed in 6.8.9 with commit 6cb6b12b78dcd8867a3fdbb1b6d0ed1df2b208d1 |
| Fixed in 6.9 with commit 2f4a4d63a193be6fd530d180bb13c3592052904c |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2024-35995 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| drivers/acpi/cppc_acpi.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/01fc53be672acae37e611c80cc0b4f3939584de3 |
| https://git.kernel.org/stable/c/1b890ae474d19800a6be1696df7fb4d9a41676e4 |
| https://git.kernel.org/stable/c/6cb6b12b78dcd8867a3fdbb1b6d0ed1df2b208d1 |
| https://git.kernel.org/stable/c/2f4a4d63a193be6fd530d180bb13c3592052904c |
