net/netvsc: replace compiler builtin overflow check
Checks
Commit Message
'__builtin_add_overflow' added to gcc in version 5, earlier versions
causing build error, like gcc 4.8.5 in RHEL7.
Replaced compiler builtin check with arithmetic check.
Fixes: cabb3c0f29f1 ("net/netvsc: check for overflow on packet info from host")
Reported-by: Raslan Darawsheh <rasland@mellanox.com>
Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
---
drivers/net/netvsc/hn_rxtx.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
Comments
Hi,
> -----Original Message-----
> From: Ferruh Yigit <ferruh.yigit@intel.com>
> Sent: Tuesday, September 8, 2020 1:07 PM
> To: dev@dpdk.org; Stephen Hemminger <sthemmin@microsoft.com>; NBU-
> Contact-kys <kys@microsoft.com>; NBU-Contact-haiyangz
> <haiyangz@microsoft.com>; NBU-Contact-longli <longli@microsoft.com>
> Cc: Ferruh Yigit <ferruh.yigit@intel.com>; Raslan Darawsheh
> <rasland@mellanox.com>
> Subject: [PATCH] net/netvsc: replace compiler builtin overflow check
>
> '__builtin_add_overflow' added to gcc in version 5, earlier versions
> causing build error, like gcc 4.8.5 in RHEL7.
>
> Replaced compiler builtin check with arithmetic check.
>
> Fixes: cabb3c0f29f1 ("net/netvsc: check for overflow on packet info from
> host")
>
> Reported-by: Raslan Darawsheh <rasland@mellanox.com>
> Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
Tested-by: Raslan Darawsheh <rasland@nvidia.com>
> ---
> drivers/net/netvsc/hn_rxtx.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/netvsc/hn_rxtx.c b/drivers/net/netvsc/hn_rxtx.c
> index d8d3f07f56..3e8d3b407d 100644
> --- a/drivers/net/netvsc/hn_rxtx.c
> +++ b/drivers/net/netvsc/hn_rxtx.c
> @@ -666,7 +666,7 @@ static void hn_rndis_rx_data(struct hn_rx_queue
> *rxq,
> struct hn_rx_bufinfo *rxb,
> void *data, uint32_t dlen)
> {
> - unsigned int data_off, data_len, total_len;
> + unsigned int data_off, data_len;
> unsigned int pktinfo_off, pktinfo_len;
> const struct rndis_packet_msg *pkt = data;
> struct hn_rxinfo info = {
> @@ -712,8 +712,8 @@ static void hn_rndis_rx_data(struct hn_rx_queue
> *rxq,
> goto error;
> }
>
> - if (__builtin_add_overflow(data_off, data_len, &total_len) ||
> - total_len > pkt->len)
> + /* overflow check */
> + if (data_len > data_len + data_off || data_len + data_off > pkt->len)
> goto error;
>
> if (unlikely(data_len < RTE_ETHER_HDR_LEN))
> --
> 2.25.4
Kindest regards
Raslan Darawsheh
On Tue, 8 Sep 2020 11:06:42 +0100
Ferruh Yigit <ferruh.yigit@intel.com> wrote:
> '__builtin_add_overflow' added to gcc in version 5, earlier versions
> causing build error, like gcc 4.8.5 in RHEL7.
Sigh. Ok, but the security folks really like __builtin_add_overflow.
On Tue, Sep 8, 2020 at 3:07 AM Ferruh Yigit <ferruh.yigit@intel.com> wrote:
> '__builtin_add_overflow' added to gcc in version 5, earlier versions
> causing build error, like gcc 4.8.5 in RHEL7.
>
> Replaced compiler builtin check with arithmetic check.
>
> Fixes: cabb3c0f29f1 ("net/netvsc: check for overflow on packet info from
> host")
>
> Reported-by: Raslan Darawsheh <rasland@mellanox.com>
> Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
>
Tested-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
> ---
> drivers/net/netvsc/hn_rxtx.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/netvsc/hn_rxtx.c b/drivers/net/netvsc/hn_rxtx.c
> index d8d3f07f56..3e8d3b407d 100644
> --- a/drivers/net/netvsc/hn_rxtx.c
> +++ b/drivers/net/netvsc/hn_rxtx.c
> @@ -666,7 +666,7 @@ static void hn_rndis_rx_data(struct hn_rx_queue *rxq,
> struct hn_rx_bufinfo *rxb,
> void *data, uint32_t dlen)
> {
> - unsigned int data_off, data_len, total_len;
> + unsigned int data_off, data_len;
> unsigned int pktinfo_off, pktinfo_len;
> const struct rndis_packet_msg *pkt = data;
> struct hn_rxinfo info = {
> @@ -712,8 +712,8 @@ static void hn_rndis_rx_data(struct hn_rx_queue *rxq,
> goto error;
> }
>
> - if (__builtin_add_overflow(data_off, data_len, &total_len) ||
> - total_len > pkt->len)
> + /* overflow check */
> + if (data_len > data_len + data_off || data_len + data_off >
> pkt->len)
> goto error;
>
> if (unlikely(data_len < RTE_ETHER_HDR_LEN))
> --
> 2.25.4
>
>
On 9/8/2020 4:47 PM, Stephen Hemminger wrote:
> On Tue, 8 Sep 2020 11:06:42 +0100
> Ferruh Yigit <ferruh.yigit@intel.com> wrote:
>
>> '__builtin_add_overflow' added to gcc in version 5, earlier versions
>> causing build error, like gcc 4.8.5 in RHEL7.
>
> Sigh. Ok, but the security folks really like __builtin_add_overflow.
>
Converting to an explicit ack:
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Applied to dpdk-next-net/main, thanks.
@@ -666,7 +666,7 @@ static void hn_rndis_rx_data(struct hn_rx_queue *rxq,
struct hn_rx_bufinfo *rxb,
void *data, uint32_t dlen)
{
- unsigned int data_off, data_len, total_len;
+ unsigned int data_off, data_len;
unsigned int pktinfo_off, pktinfo_len;
const struct rndis_packet_msg *pkt = data;
struct hn_rxinfo info = {
@@ -712,8 +712,8 @@ static void hn_rndis_rx_data(struct hn_rx_queue *rxq,
goto error;
}
- if (__builtin_add_overflow(data_off, data_len, &total_len) ||
- total_len > pkt->len)
+ /* overflow check */
+ if (data_len > data_len + data_off || data_len + data_off > pkt->len)
goto error;
if (unlikely(data_len < RTE_ETHER_HDR_LEN))