From: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> mainline inclusion from mainline-v7.0-rc1 commit 87880af2d24e62a84ed19943dbdd524f097172f2 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/14747 CVE: CVE-2026-43201 Reference: https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commi... -------------------------------- If the BIOS generates a very small ARM Processor Error, or an incomplete one, the current logic will fail to deferrence err->section_length and ctx_info->size Add checks to avoid that. With such changes, such GHESv2 records won't cause OOPSes like this: [ 1.492129] Internal error: Oops: 0000000096000005 [#1] SMP [ 1.495449] Modules linked in: [ 1.495820] CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted 6.18.0-rc1-00017-gabadcc3553dd-dirty #18 PREEMPT [ 1.496125] Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 02/02/2022 [ 1.496433] Workqueue: kacpi_notify acpi_os_execute_deferred [ 1.496967] pstate: 814000c5 (Nzcv daIF +PAN -UAO -TCO +DIT -SSBS BTYPE=--) [ 1.497199] pc : log_arm_hw_error+0x5c/0x200 [ 1.497380] lr : ghes_handle_arm_hw_error+0x94/0x220 0xffff8000811c5324 is in log_arm_hw_error (../drivers/ras/ras.c:75). 70 err_info = (struct cper_arm_err_info *)(err + 1); 71 ctx_info = (struct cper_arm_ctx_info *)(err_info + err->err_info_num); 72 ctx_err = (u8 *)ctx_info; 73 74 for (n = 0; n < err->context_info_num; n++) { 75 sz = sizeof(struct cper_arm_ctx_info) + ctx_info->size; 76 ctx_info = (struct cper_arm_ctx_info *)((long)ctx_info + sz); 77 ctx_len += sz; 78 } 79 and similar ones while trying to access section_length on an error dump with too small size. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Hanjun Guo <guohanjun@huawei.com> [ rjw: Subject tweaks ] Link: https://patch.msgid.link/7fd9f38413be05ee2d7cfdb0dc31ea2274cf1a54.1767871950... Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Conflicts: drivers/acpi/apei/ghes.c drivers/ras/ras.c [conflicts due to not merged 96b010536ee0 ("efi/cper: align ARM CPER type with UEFI 2.9A/2.10 specs")] Signed-off-by: Mingrui Liu <liumingrui@huawei.com> Signed-off-by: Liu Mingrui <liumingrui@huawei.com> --- drivers/acpi/apei/ghes.c | 34 +++++++++++++++++++++++++++++----- drivers/ras/ras.c | 6 +++++- 2 files changed, 34 insertions(+), 6 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index bdaf28b5ebcc..f17a20fcf4f8 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -611,27 +611,51 @@ static bool ghes_handle_arm_hw_error(struct acpi_hest_generic_data *gdata, { struct cper_sec_proc_arm *err = acpi_hest_get_payload(gdata); int flags = sync ? MF_ACTION_REQUIRED : 0; + int length = gdata->error_data_length; bool queued = false; int sec_sev, i; bool critical; char *p; sec_sev = ghes_severity(gdata->error_severity); + if (length >= sizeof(*err)) { #ifdef CONFIG_RAS_ARM_EVENT_INFO - log_arm_hw_error(err, sec_sev); + log_arm_hw_error(err, sec_sev); #else - log_arm_hw_error(err); + log_arm_hw_error(err); #endif + } else { + pr_warn(FW_BUG "arm error length: %d\n", length); + pr_warn(FW_BUG "length is too small\n"); + pr_warn(FW_BUG "firmware-generated error record is incorrect\n"); + return false; + } + if (sev != GHES_SEV_RECOVERABLE || sec_sev != GHES_SEV_RECOVERABLE) return false; p = (char *)(err + 1); critical = ghes_armp_vendor_critical_error(err, sync); + length -= sizeof(err); + for (i = 0; i < err->err_info_num; i++) { - struct cper_arm_err_info *err_info = (struct cper_arm_err_info *)p; - bool is_cache = (err_info->type == CPER_ARM_CACHE_ERROR); - bool has_pa = (err_info->validation_bits & CPER_ARM_INFO_VALID_PHYSICAL_ADDR); const char *error_type = "unknown error"; + struct cper_arm_err_info *err_info; + bool is_cache, has_pa; + + /* Ensure we have enough data for the error info header */ + if (length < sizeof(*err_info)) + break; + + err_info = (struct cper_arm_err_info *)p; + + /* Validate the claimed length before using it */ + length -= err_info->length; + if (length < 0) + break; + + is_cache = err_info->type == CPER_ARM_CACHE_ERROR; + has_pa = (err_info->validation_bits & CPER_ARM_INFO_VALID_PHYSICAL_ADDR); /* * The field (err_info->error_info & BIT(26)) is fixed to set to diff --git a/drivers/ras/ras.c b/drivers/ras/ras.c index 547e058e2d56..ecfaff12816c 100644 --- a/drivers/ras/ras.c +++ b/drivers/ras/ras.c @@ -77,7 +77,11 @@ void log_arm_hw_error(struct cper_sec_proc_arm *err) ctx_info = (struct cper_arm_ctx_info *)(err_info + err->err_info_num); ctx_err = (u8 *)ctx_info; for (n = 0; n < err->context_info_num; n++) { - sz = sizeof(struct cper_arm_ctx_info) + ctx_info->size; + sz = sizeof(struct cper_arm_ctx_info); + + if (sz + (long)ctx_info - (long)err >= err->section_length) + sz += ctx_info->size; + ctx_info = (struct cper_arm_ctx_info *)((long)ctx_info + sz); ctx_len += sz; } -- 2.34.1