From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A62B1416D15; Thu, 9 Jul 2026 16:28:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783614492; cv=none; b=tytafgMRPSSPqu3hv8c0YH9unwHJgBuQ4gFeDfnDbqsV3I76WSc9P/wREzpePrgQwciODKPH0ija+7KvEqVX2UoGKHpD/drZ2sNxLb8gqi+7eTX6fmysF17ytSjZU75xgLR9L9zSmTWmQg5NMtDJxNHdnikhBU++GIdxWRNiELM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783614492; c=relaxed/simple; bh=8qbiXfw397WD3m24m4YanA3EcCXbkeG2BFQeslLWSvE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=iwrUjDVdIm9V3gFB6LirO4w1na3IsFr5T+J/cHfl4t6+bCwMUklcrftQZ6QKufvLWAvxZeM/qGhaIV0JtNo4ff508Q2cYhRQx86JwhXT7sqcbSzy3j9ASnhRFUoru0c62WMipyNq1rR6AqP2Wizcm8IPLF1IdNm/DNC+W9dYlDw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 35E651F000E9; Thu, 9 Jul 2026 16:28:11 +0000 (UTC) From: Dave Jiang To: linux-acpi@vger.kernel.org, linux-cxl@vger.kernel.org Cc: rafael@kernel.org, tony.luck@intel.com, bp@alien8.de, guohanjun@huawei.com, mchehab@kernel.org, xueshuai@linux.alibaba.com Subject: [PATCH 2/4] ACPI: APEI: GHES: Bound CXL event record copy to the firmware section length Date: Thu, 9 Jul 2026 09:28:05 -0700 Message-ID: <20260709162807.1957783-3-dave.jiang@intel.com> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260709162807.1957783-1-dave.jiang@intel.com> References: <20260709162807.1957783-1-dave.jiang@intel.com> Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit cxl_cper_post_event() blindly copies a fixed sizeof(struct cxl_cper_event_rec) out of the firmware-provided CPER section without checking the length. Pass gdata->err_data_length into the function and reject a section too small to hold the record before the copy. Link: https://sashiko.dev/#/patchset/20260617-topics-ahmtib01-ras_ffh_arm_internal_review-v6-0-91f725174aa0@arm.com?part=6 Fixes: 5e4a264bf8b5 ("acpi/ghes: Process CXL Component Events") Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Dave Jiang --- drivers/acpi/apei/ghes.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index 9b6917698ed2..7b465e2afcb0 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -815,10 +815,21 @@ static DEFINE_SPINLOCK(cxl_cper_work_lock); struct work_struct *cxl_cper_work; static void cxl_cper_post_event(enum cxl_event_type event_type, - struct cxl_cper_event_rec *rec) + struct cxl_cper_event_rec *rec, u32 len) { struct cxl_cper_work_data wd; + /* + * The record is copied whole below, so the firmware-provided section + * must be at least as large as the record. cper_estatus_check() only + * validates the section fits the error block, not that it satisfies a + * given section type's size, so guard the fixed-size copy here. + */ + if (len < sizeof(*rec)) { + pr_err(FW_WARN "CXL CPER section too small (%u)\n", len); + return; + } + if (rec->hdr.length <= sizeof(rec->hdr) || rec->hdr.length > sizeof(*rec)) { pr_err(FW_WARN "CXL CPER Invalid section length (%u)\n", @@ -949,15 +960,18 @@ static void ghes_do_proc(struct ghes *ghes, } else if (guid_equal(sec_type, &CPER_SEC_CXL_GEN_MEDIA_GUID)) { struct cxl_cper_event_rec *rec = acpi_hest_get_payload(gdata); - cxl_cper_post_event(CXL_CPER_EVENT_GEN_MEDIA, rec); + cxl_cper_post_event(CXL_CPER_EVENT_GEN_MEDIA, rec, + gdata->error_data_length); } else if (guid_equal(sec_type, &CPER_SEC_CXL_DRAM_GUID)) { struct cxl_cper_event_rec *rec = acpi_hest_get_payload(gdata); - cxl_cper_post_event(CXL_CPER_EVENT_DRAM, rec); + cxl_cper_post_event(CXL_CPER_EVENT_DRAM, rec, + gdata->error_data_length); } else if (guid_equal(sec_type, &CPER_SEC_CXL_MEM_MODULE_GUID)) { struct cxl_cper_event_rec *rec = acpi_hest_get_payload(gdata); - cxl_cper_post_event(CXL_CPER_EVENT_MEM_MODULE, rec); + cxl_cper_post_event(CXL_CPER_EVENT_MEM_MODULE, rec, + gdata->error_data_length); } else { void *err = acpi_hest_get_payload(gdata); -- 2.54.0