2021-07-24 12:24:10

by Len Baker

[permalink] [raw]
Subject: Re: [PATCH] drivers/bluetooth: Remove all strcpy() uses

Hi,

On Sun, Jul 18, 2021 at 05:12:55PM +0100, Adam Sampson wrote:
> Len Baker <[email protected]> writes:
>
> > strcpy() performs no bounds checking on the destination buffer. This
> > could result in linear overflows beyond the end of the buffer, leading
> > to all kinds of misbehaviors. The safe replacement is strscpy() but in
> > this case it is better to use the scnprintf to simplify the arithmetic.
> >
> > This is a previous step in the path to remove the strcpy() function
> > entirely from the kernel.
> >
> > Signed-off-by: Len Baker <[email protected]>
> > ---
> > drivers/bluetooth/btmrvl_sdio.c | 27 +++++++++++++--------------
> > 1 file changed, 13 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/bluetooth/btmrvl_sdio.c b/drivers/bluetooth/btmrvl_sdio.c
> > index cddd350beba3..d6674b367e05 100644
> > --- a/drivers/bluetooth/btmrvl_sdio.c
> > +++ b/drivers/bluetooth/btmrvl_sdio.c
> > @@ -1350,6 +1350,7 @@ static void btmrvl_sdio_coredump(struct device *dev)
> > u8 *dbg_ptr, *end_ptr, *fw_dump_data, *fw_dump_ptr;
> [...]
> > + size += scnprintf(fw_dump_ptr + size,
> > + sizeof(fw_dump_ptr) - size,
> [...]
> > + size += scnprintf(fw_dump_ptr + size,
> > + sizeof(fw_dump_ptr) - size,
>
> sizeof(fw_dump_ptr) there looks wrong -- you want the size of the buffer
> it points to (fw_dump_len + 1)?

Apologies. I will work on it and I will send a new version for review.
Thanks for the feedback.

>
> Thanks,
>
> --
> Adam Sampson <[email protected]> <http://offog.org/>

Regards,
Len