Re: [PATCH] dmaengine: idxd: Fix dereference on uninitialized pointer conf_dev

[Colin King (gmail)]

On 11/08/2025 11:16, Dan Carpenter wrote:
> On Mon, Aug 11, 2025 at 10:58:36AM +0100, Colin Ian King wrote:
> > Currently if the allocation for wq fails on the initial iteration in
> > the setup loop the error exit path to err will call put_device on
> > an uninitialized pointer conf_dev. Fix this by initializing conf_dev
> > to NULL, note that put_device will ignore a NULL device pointer so no
> > null pointer dereference issues occur on this call.
> >
> > Fixes: 3fd2f4bc010c ("dmaengine: idxd: fix memory leak in error handling path of idxd_setup_wqs")
> >
> > Signed-off-by: Colin Ian King <colin.i.king@xxxxxxxxx>
> > ---
>
> No.  This isn't the right fix.  I basically wrote out the correct fix
> in my bug report:
> https://lore.kernel.org/all/aDQt3_rZjX-VuHJW@stanley.mountain/
> Shuai Xue sent a fix as well but that patch wasn't right either but I
> didn't review it until now.
>
> It's easiest if I send the fix and give you Reported-by credit.
>
> regards,
> dan carpenter

Thanks Dan, always appreciate your input to these issues.

Colin

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