mt76: usb: fix possible memory leak in mt76u_buf_free

Move q->ndesc initialization before the for loop in mt76u_alloc_rx
since otherwise allocated urbs will not be freed in mt76u_buf_free
Double-check scatterlist pointer in mt76u_buf_free

Fixes: b40b15e152 ("mt76: add usb support to mt76 layer")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
This commit is contained in:
Lorenzo Bianconi 2019-02-10 22:49:14 +01:00 committed by Felix Fietkau
parent bdba48d57a
commit cb83585e11

View File

@ -330,10 +330,16 @@ int mt76u_buf_alloc(struct mt76_dev *dev, struct mt76u_buf *buf,
void mt76u_buf_free(struct mt76u_buf *buf)
{
struct urb *urb = buf->urb;
struct scatterlist *sg;
int i;
for (i = 0; i < urb->num_sgs; i++)
skb_free_frag(sg_virt(&urb->sg[i]));
for (i = 0; i < urb->num_sgs; i++) {
sg = &urb->sg[i];
if (!sg)
continue;
skb_free_frag(sg_virt(sg));
}
usb_free_urb(buf->urb);
}
EXPORT_SYMBOL_GPL(mt76u_buf_free);
@ -537,7 +543,8 @@ static int mt76u_alloc_rx(struct mt76_dev *dev)
nsgs = 1;
}
for (i = 0; i < MT_NUM_RX_ENTRIES; i++) {
q->ndesc = MT_NUM_RX_ENTRIES;
for (i = 0; i < q->ndesc; i++) {
err = mt76u_buf_alloc(dev, &q->entry[i].ubuf,
nsgs, q->buf_size,
SKB_WITH_OVERHEAD(q->buf_size),
@ -545,7 +552,6 @@ static int mt76u_alloc_rx(struct mt76_dev *dev)
if (err < 0)
return err;
}
q->ndesc = MT_NUM_RX_ENTRIES;
return mt76u_submit_rx_buffers(dev);
}