cxgb4: prevent potential integer overflow on 32bit

[PATCH] cxgb4: prevent potential integer overflow on 32bit

Posted by Dan Carpenter 1 year, 2 months ago

The "gl->tot_len" variable is controlled by the user.  It comes from
process_responses().  On 32bit systems, the "gl->tot_len +
sizeof(struct cpl_pass_accept_req) + sizeof(struct rss_header)" addition
could have an integer wrapping bug.  Use size_add() to prevent this.

Fixes: a08943947873 ("crypto: chtls - Register chtls with net tls")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
---
This is from static analysis.  I've spent some time reviewing this code
but I might be wrong.

 drivers/infiniband/hw/cxgb4/device.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/hw/cxgb4/device.c b/drivers/infiniband/hw/cxgb4/device.c
index 80970a1738f8..034b85c42255 100644
--- a/drivers/infiniband/hw/cxgb4/device.c
+++ b/drivers/infiniband/hw/cxgb4/device.c
@@ -1114,8 +1114,10 @@ static inline struct sk_buff *copy_gl_to_skb_pkt(const struct pkt_gl *gl,
 	 * The math here assumes sizeof cpl_pass_accept_req >= sizeof
 	 * cpl_rx_pkt.
 	 */
-	skb = alloc_skb(gl->tot_len + sizeof(struct cpl_pass_accept_req) +
-			sizeof(struct rss_header) - pktshift, GFP_ATOMIC);
+	skb = alloc_skb(size_add(gl->tot_len,
+				 sizeof(struct cpl_pass_accept_req) +
+				 sizeof(struct rss_header)) - pktshift,
+			GFP_ATOMIC);
 	if (unlikely(!skb))
 		return NULL;
 
-- 
2.45.2

Re: [PATCH] cxgb4: prevent potential integer overflow on 32bit

Posted by Jason Gunthorpe 1 year, 1 month ago

On Sat, Nov 30, 2024 at 01:01:37PM +0300, Dan Carpenter wrote:
> The "gl->tot_len" variable is controlled by the user.  It comes from
> process_responses().  On 32bit systems, the "gl->tot_len +
> sizeof(struct cpl_pass_accept_req) + sizeof(struct rss_header)" addition
> could have an integer wrapping bug.  Use size_add() to prevent this.
> 
> Fixes: a08943947873 ("crypto: chtls - Register chtls with net tls")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---
> This is from static analysis.  I've spent some time reviewing this code
> but I might be wrong.

Applied to for-next

I fixed the Fixes line:

    Fixes: 1cab775c3e75 ("RDMA/cxgb4: Fix LE hash collision bug for passive open connection")

Thanks,
Jason

Re: [PATCH] cxgb4: prevent potential integer overflow on 32bit

Posted by Dan Carpenter 1 year, 1 month ago

On Mon, Dec 09, 2024 at 02:55:56PM -0400, Jason Gunthorpe wrote:
> On Sat, Nov 30, 2024 at 01:01:37PM +0300, Dan Carpenter wrote:
> > The "gl->tot_len" variable is controlled by the user.  It comes from
> > process_responses().  On 32bit systems, the "gl->tot_len +
> > sizeof(struct cpl_pass_accept_req) + sizeof(struct rss_header)" addition
> > could have an integer wrapping bug.  Use size_add() to prevent this.
> > 
> > Fixes: a08943947873 ("crypto: chtls - Register chtls with net tls")
> > Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> > ---
> > This is from static analysis.  I've spent some time reviewing this code
> > but I might be wrong.
> 
> Applied to for-next
> 
> I fixed the Fixes line:
> 
>     Fixes: 1cab775c3e75 ("RDMA/cxgb4: Fix LE hash collision bug for passive open connection")

Aw crud.  There are two implementations of copy_gl_to_skb_pkt() and I
only patched one.  It's pretty weird how I mixed up the Fixes tags.
Anyway, I'll patch drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls_main.c
as well.

regards,
dan carpenter