Re: [PATCH] EDAC: altera: Delete an inappropriate dma_free_coherent() call in altr_sdr_mc_err_inject_write()

[Borislav Petkov]

On Thu, Jul 31, 2025 at 04:15:27AM +0100, Salah Triki wrote:
> `dma_free_coherent()` must only be called if the corresponding
> `dma_alloc_coherent()` call has succeeded. Calling it when the allocation
> fails leads to undefined behavior.
> 
> Add a check to ensure that the memory is only freed when the allocation
> was successful.
> 
> Signed-off-by: Salah Triki <salah.triki@xxxxxxxxx>
> Fixes: 71bcada88b0f3 ("edac: altera: Add Altera SDRAM EDAC support")
> Cc: Markus Elfring <Markus.Elfring@xxxxxx>
> Cc: Dinh Nguyen <dinguyen@xxxxxxxxxx>
> Cc: Borislav Petkov <bp@xxxxxxxxx>
> Cc: Tony Luck <tony.luck@xxxxxxxxx>
> Cc: James Morse <james.morse@xxxxxxx>
> Cc: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
> Cc: Robert Richter <rric@xxxxxxxxxx>
> Cc: linux-edac@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Cc: stable@xxxxxxxxxxxxxxx
> ---
>  drivers/edac/altera_edac.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
> index cae52c654a15..7685a8550d4b 100644
> --- a/drivers/edac/altera_edac.c
> +++ b/drivers/edac/altera_edac.c
> @@ -128,7 +128,6 @@ static ssize_t altr_sdr_mc_err_inject_write(struct file *file,
>  
>  	ptemp = dma_alloc_coherent(mci->pdev, 16, &dma_handle, GFP_KERNEL);
>  	if (!ptemp) {
> -		dma_free_coherent(mci->pdev, 16, ptemp, dma_handle);
>  		edac_printk(KERN_ERR, EDAC_MC,
>  			    "Inject: Buffer Allocation error\n");
>  		return -ENOMEM;
> -- 


Applied, thanks.

-- 
Regards/Gruss,
    Boris.

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