[PATCH] ufs: core: Fix heap corruption due to out of bounds write

[Marek Vasut]

On 3/30/26 1:11 AM, Marek Vasut wrote:
> The ufshcd_read_string_desc() can perform out of bounds write and
> corrupt heap in case the input utf-16 string contains code points
> which convert to anything more than plain 7-bit ASCII string.
> 
> This occurs because utf16_to_utf8(dst, src, size) in U-Boot behaves
> differently than Linux utf16s_to_utf8s(..., maxlen), but the porting
> process did not take that into consideration. The U-Boot variant of
> the function converts up to $size utf-16 fixed-length 16-bit input
> characters into as many 1..4 Byte long variable-length utf-8 output
> characters. That means for 16 Byte input, the output can be up to 64
> Bytes long. The Linux variant converts up utf-16 input into up to
> $maxlen Bytes worth of utf-8 output, but stops at the $maxlen limit.
> That means for 16 Byte input with maxlen=32, the processing will stop
> after writing 32 output Bytes.
> 
> In case of U-Boot, use of utf16_to_utf8() leads to potential corruption
> of data past the $size Bytes and therefore corruption of surrounding
> content on the heap.
> 
> The fix is as simple, allocate buffer that is sufficient to fit the
> utf-8 string. The rest of the code in ufshcd_read_string_desc() does
> correctly limit the buffer to fit into the DMA descriptor afterward.
> 
> Signed-off-by: Marek Vasut <marek.vasut+renesas at mailbox.org>
> ---
> NOTE: This is for 2026.04, but please do test it on your hardware too.

It seems this memory corruption bugfix missed 2026.04 ?