Re: [PATCH v4 06/13] ACPI: extlog: Validate PCIe error section length before payload access

[Jonathan Cameron <jic23@kernel.org>]

On Mon, 24 Aug 2026 10:49:29 -0700
Dave Jiang <dave.jiang@intel.com> wrote:

> extlog_print_pcie() reads pcie_err->validation_bits and device_id and
> copies the 96-byte aer_info buffer without checking that
> gdata->error_data_length is big enough for a struct cper_sec_pcie. The
> cper_estatus_check() call added earlier keeps the read inside the estatus
> block, but a short section still gets stale adjacent bytes treated as PCIe
> error data.
> 
> Reject a section too small to hold the record before touching any field,
> and warn: a truncated section means firmware is emitting malformed records.
> 
> Reported-by: sashiko-bot@kernel.org
> Closes: https://lore.kernel.org/linux-cxl/20260709165457.8BA181F000E9@smtp.kernel.org/
> Fixes: e778ffefa34d ("ACPI: extlog: Trace CPER PCI Express Error Section")
> Reviewed-by: Alison Schofield <alison.schofield@intel.com>
> Reviewed-by: Shuai Xue <xueshuai@linux.alibaba.com>
> Assisted-by: Claude:claude-opus-4-8
> Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Reviewed-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>