Re: [PATCH] nvmem: core: Fix OOB read for bit offsets of more than one byte

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Mon, Sep 01, 2025 at 09:29:43AM +0200, Janne Grunau wrote:
> When the bit offset is BITS_PER_BYTE or larger the read position is
> advanced by `bytes_offset`. This is not taken into account in the
> per-byte read loop which still reads `cell->bytes` resulting in an out of
> bounds read of `bytes_offset` bytes. The information read OOB does not
> leak directly as the erroneously read bits are cleared.
> 
> Detected by KASAN while looking for a use-after-free in simplefb.c.
> 
> Fixes: 7a06ef7510779 ("nvmem: core: fix bit offsets of more than one byte")
> Signed-off-by: Janne Grunau <j@jannau.net>
> ---
>  drivers/nvmem/core.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
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thanks,

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