g>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
[ rjw: Subject tweaks ]
Link: https://patch.msgid.link/7fd9f38413be05ee2d7cfdb0dc31ea2274cf1a54.1767871950.git.mchehab+huawei@kernel.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/acpi/apei/ghes.c | 32 ++++++++++++++++++++++++++++----
 drivers/ras/ras.c        |  6 +++++-
 2 files changed, 33 insertions(+), 5 deletions(-)

diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index a37c8fb574832..77ea7a5b761f1 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -556,21 +556,45 @@ 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;
 	char error_type[120];
 	bool queued = false;
 	int sec_sev, i;
 	char *p;
 
 	sec_sev = ghes_severity(gdata->error_severity);
-	log_arm_hw_error(err, sec_sev);
+	if (length >= sizeof(*err)) {
+		log_arm_hw_error(err, sec_sev);
+	} 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);
+	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);
+		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 2a5b5a9fdcb36..03df3db623346 100644
--- a/drivers/ras/ras.c
+++ b/drivers/ras/ras.c
@@ -72,7 +72,11 @@ void log_arm_hw_error(struct cper_sec_proc_arm *err, const u8 sev)
 	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;
 	}
-- 
2.51.0[PATCH 6.19 067/844] APEI/GHES: ARM processor Error: don't go past allocated memorySasha Levin <sashal@kernel.org> undefinedlinux-kernel@vger.kernel.org, stable@vger.kernel.org undefined undefined undefined undefined undefined undefined undefined