Hi,
Colin King <colin.king@xxxxxxxxxxxxx> writes:
> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> Writing to td->next should be avoided after td has been freed using
> dma_pool_free. The intent was to nullify the next pointer, but this
> is potentially dangerous once it is back in the pool. Remove it.
>
> Detected by CoverityScan, CID#1091173 ("Write tp pointer after free")
>
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> ---
> drivers/usb/gadget/udc/pch_udc.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/usb/gadget/udc/pch_udc.c b/drivers/usb/gadget/udc/pch_udc.c
> index 84dcbcd756f0..08bbe2c24134 100644
> --- a/drivers/usb/gadget/udc/pch_udc.c
> +++ b/drivers/usb/gadget/udc/pch_udc.c
> @@ -1523,7 +1523,6 @@ static void pch_udc_free_dma_chain(struct pch_udc_dev *dev,
> td = phys_to_virt(addr);
> addr2 = (dma_addr_t)td->next;
> dma_pool_free(dev->data_requests, td, addr);
> - td->next = 0x00;
I already have a patch for this, thanks
1f459262b0e1649a1e5ad12fa4c66eb76c2220ce
Author: Gustavo A. R. Silva <garsilva@xxxxxxxxxxxxxx>
AuthorDate: Fri Mar 10 15:39:32 2017 -0600
Commit: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
CommitDate: Wed Mar 22 11:21:10 2017 +0200
usb: gadget: udc: remove pointer dereference after free
Remove pointer dereference after free.
Addresses-Coverity-ID: 1091173
Acked-by: Michal Nazarewicz <mina86@xxxxxxxxxx>
Signed-off-by: Gustavo A. R. Silva <garsilva@xxxxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
1 file changed, 1 deletion(-)
drivers/usb/gadget/udc/pch_udc.c | 1 -
modified drivers/usb/gadget/udc/pch_udc.c
@@ -1523,7 +1523,6 @@ static void pch_udc_free_dma_chain(struct pch_udc_dev *dev,
td = phys_to_virt(addr);
addr2 = (dma_addr_t)td->next;
pci_pool_free(dev->data_requests, td, addr);
- td->next = 0x00;
addr = addr2;
}
req->chain_len = 1;
--
balbi
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