diff options
| author | Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> | 2025-12-30 22:16:09 -0800 |
|---|---|---|
| committer | Sasha Levin <sashal@kernel.org> | 2026-03-04 07:21:27 -0500 |
| commit | 4d7a8f5f28187e3d2958b2a134473da2665207e7 (patch) | |
| tree | dd3b03e9ea7c34bb8bdd3e459ef72dd556fe6fc7 /arch/x86 | |
| parent | e92e02c2dc900d17c587ee78807d5f5a93359fc4 (diff) | |
x86/kexec: add a sanity check on previous kernel's ima kexec buffer
[ Upstream commit c5489d04337b47e93c0623e8145fcba3f5739efd ]
When the second-stage kernel is booted via kexec with a limiting command
line such as "mem=<size>", the physical range that contains the carried
over IMA measurement list may fall outside the truncated RAM leading to a
kernel panic.
BUG: unable to handle page fault for address: ffff97793ff47000
RIP: ima_restore_measurement_list+0xdc/0x45a
#PF: error_code(0x0000) – not-present page
Other architectures already validate the range with page_is_ram(), as done
in commit cbf9c4b9617b ("of: check previous kernel's ima-kexec-buffer
against memory bounds") do a similar check on x86.
Without carrying the measurement list across kexec, the attestation
would fail.
Link: https://lkml.kernel.org/r/20251231061609.907170-4-harshit.m.mogalapalli@oracle.com
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Fixes: b69a2afd5afc ("x86/kexec: Carry forward IMA measurement log on kexec")
Reported-by: Paul Webb <paul.x.webb@oracle.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Cc: Alexander Graf <graf@amazon.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Betkov <bp@alien8.de>
Cc: guoweikang <guoweikang.kernel@gmail.com>
Cc: Henry Willard <henry.willard@oracle.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Bohac <jbohac@suse.cz>
Cc: Joel Granados <joel.granados@kernel.org>
Cc: Jonathan McDowell <noodles@fb.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Sohil Mehta <sohil.mehta@intel.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Yifei Liu <yifei.l.liu@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/setup.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 1b2edd07a3e1..383d4a4784f5 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -439,9 +439,15 @@ int __init ima_free_kexec_buffer(void) int __init ima_get_kexec_buffer(void **addr, size_t *size) { + int ret; + if (!ima_kexec_buffer_size) return -ENOENT; + ret = ima_validate_range(ima_kexec_buffer_phys, ima_kexec_buffer_size); + if (ret) + return ret; + *addr = __va(ima_kexec_buffer_phys); *size = ima_kexec_buffer_size; |