Messages in this thread | | | Subject | Re: [PATCH] staging: vt6655: check for memory allocation failures | From | Jia-Ju Bai <> | Date | Wed, 28 Mar 2018 17:55:57 +0800 |
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On 2018/3/28 14:31, Ji-Hun Kim wrote: > There are no null pointer checking on rd_info and td_info values which > are allocated by kzalloc. It has potential null pointer dereferencing > issues. Add return when allocation is failed. > > Signed-off-by: Ji-Hun Kim <ji_hun.kim@samsung.com> > --- > drivers/staging/vt6655/device_main.c | 12 ++++++++---- > 1 file changed, 8 insertions(+), 4 deletions(-) > > diff --git a/drivers/staging/vt6655/device_main.c b/drivers/staging/vt6655/device_main.c > index fbc4bc6..5d0ba94 100644 > --- a/drivers/staging/vt6655/device_main.c > +++ b/drivers/staging/vt6655/device_main.c > @@ -539,7 +539,8 @@ static void device_init_rd0_ring(struct vnt_private *priv) > i ++, curr += sizeof(struct vnt_rx_desc)) { > desc = &priv->aRD0Ring[i]; > desc->rd_info = kzalloc(sizeof(*desc->rd_info), GFP_KERNEL); > - > + if (WARN_ON(!desc->rd_info)) > + return; > if (!device_alloc_rx_buf(priv, desc)) > dev_err(&priv->pcid->dev, "can not alloc rx bufs\n"); > > @@ -563,7 +564,8 @@ static void device_init_rd1_ring(struct vnt_private *priv) > i ++, curr += sizeof(struct vnt_rx_desc)) { > desc = &priv->aRD1Ring[i]; > desc->rd_info = kzalloc(sizeof(*desc->rd_info), GFP_KERNEL); > - > + if (WARN_ON(!desc->rd_info)) > + return; > if (!device_alloc_rx_buf(priv, desc)) > dev_err(&priv->pcid->dev, "can not alloc rx bufs\n"); > > @@ -621,7 +623,8 @@ static void device_init_td0_ring(struct vnt_private *priv) > i++, curr += sizeof(struct vnt_tx_desc)) { > desc = &priv->apTD0Rings[i]; > desc->td_info = kzalloc(sizeof(*desc->td_info), GFP_KERNEL); > - > + if (WARN_ON(!desc->td_info)) > + return; > desc->td_info->buf = priv->tx0_bufs + i * PKT_BUF_SZ; > desc->td_info->buf_dma = priv->tx_bufs_dma0 + i * PKT_BUF_SZ; > > @@ -646,7 +649,8 @@ static void device_init_td1_ring(struct vnt_private *priv) > i++, curr += sizeof(struct vnt_tx_desc)) { > desc = &priv->apTD1Rings[i]; > desc->td_info = kzalloc(sizeof(*desc->td_info), GFP_KERNEL); > - > + if (WARN_ON(!desc->td_info)) > + return; > desc->td_info->buf = priv->tx1_bufs + i * PKT_BUF_SZ; > desc->td_info->buf_dma = priv->tx_bufs_dma1 + i * PKT_BUF_SZ; >
I think the bugs you found are right. But your patch is not correct, because it is dangerous to return directly. I think you should return an error and then implement error handling code for these functions.
Best wishes, Jia-Ju Bai
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