Re: [PATCH v2 3/3] accel/ivpu: Limit firmware log name prints to field size

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] Unbounded string read from firmware data in `ivpu_fw_parse`.
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commit 7d0d9c625b89d41a9d3cbe859e6e2b33348102cf
Author: Dawid Osuchowski <dawid.osuchowski@linux.intel.com>

accel/ivpu: Limit firmware log name prints to field size
    
This patch fixes an issue where the NPU firmware log name field is printed
using an unbounded string conversion. By enforcing a precision limit based
on the field's size, it prevents out-of-bounds memory reads if the firmware
string is missing its NUL terminator.

Closes: https://sashiko.dev/#/patchset/20260827102339.281799-1-dawid.osuchowski@linux.intel.com?part=2

> diff --git a/drivers/accel/ivpu/ivpu_fw_log.c b/drivers/accel/ivpu/ivpu_fw_log.c
> index 4f9055aa9d33f..9eafc42120b6a 100644
> --- a/drivers/accel/ivpu/ivpu_fw_log.c
> +++ b/drivers/accel/ivpu/ivpu_fw_log.c
> @@ -69,9 +69,9 @@ static int fw_log_from_bo(struct ivpu_device *vdev, struct ivpu_bo *bo, u32 *off
>  	*offset += size;
>  
>  	ivpu_dbg(vdev, FW_BOOT,
> -		 "FW log name \"%s\", write offset 0x%x size 0x%x, wrap count %d, hdr version %d size %d format %d, alignment %d",
> -		 log->name, log->write_index, size, log->wrap_count, log->header_version,
> -		 header_size, log->format, log->alignment);
> +		 "FW log name \"%.*s\", write offset 0x%x size 0x%x, wrap count %d, hdr version %d size %d format %d, alignment %d",
> +		 (int)ARRAY_SIZE(log->name), log->name, log->write_index, size, log->wrap_count,
> +		 log->header_version, header_size, log->format, log->alignment);

[Severity: High]
This isn't a bug introduced by this patch, but since this patch fixes an
unbounded string read, is there a similar issue in ivpu_fw_parse() when
reading the firmware version?

Looking at drivers/accel/ivpu/ivpu_fw.c:ivpu_fw_parse():

	if (!scnprintf(fw->version, sizeof(fw->version), "%s", fw->file->data + VPU_FW_HEADER_SIZE))
		ivpu_warn(vdev, "Missing firmware version\n");

The scnprintf() function evaluates the length of the source string until a NUL
byte is found when no precision is provided for "%s", regardless of the
destination buffer size.

If the loaded firmware file lacks a NUL terminator at VPU_FW_HEADER_SIZE,
could this lead to an out-of-bounds read past the loaded firmware data?

This could trigger a page fault and expose adjacent kernel memory if a
malformed firmware file is supplied.

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Sashiko AI review · https://sashiko.dev/#/patchset/20260901125749.404338-1-dawid.osuchowski@linux.intel.com?part=3