net/mlx5: fix the building with flexible array
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Commit Message
With some higher GCC/CLANG version, it is not recommended to use a
structure with a tailing flexible array inside another structure.
Accessing this array may be considered as a risk to corrupt the
following field even if it is by intention.
The error below was observed:
drivers/net/mlx5/linux/mlx5_ethdev_os.c: In function 'mlx5_get_flag_dropless_rq':
drivers/net/mlx5/linux/mlx5_ethdev_os.c:1679:42: error: invalid use of structure with flexible array member [-Werror=pedantic]
1679 | struct ethtool_sset_info hdr;
| ^~~
Changing it to memory dynamic allocation method will help to get
rid of this complain.
Fixes: e848218741ea ("net/mlx5: check delay drop settings in kernel driver")
Cc: stable@dpdk.org
Signed-off-by: Bing Zhao <bingz@nvidia.com>
---
drivers/net/mlx5/linux/mlx5_ethdev_os.c | 22 +++++++++++++---------
1 file changed, 13 insertions(+), 9 deletions(-)
Comments
31/10/2022 19:24, Bing Zhao:
> With some higher GCC/CLANG version, it is not recommended to use a
> structure with a tailing flexible array inside another structure.
> Accessing this array may be considered as a risk to corrupt the
> following field even if it is by intention.
>
> The error below was observed:
>
> drivers/net/mlx5/linux/mlx5_ethdev_os.c: In function 'mlx5_get_flag_dropless_rq':
> drivers/net/mlx5/linux/mlx5_ethdev_os.c:1679:42: error: invalid use of structure with flexible array member [-Werror=pedantic]
> 1679 | struct ethtool_sset_info hdr;
> | ^~~
>
> Changing it to memory dynamic allocation method will help to get
> rid of this complain.
>
> Fixes: e848218741ea ("net/mlx5: check delay drop settings in kernel driver")
> Cc: stable@dpdk.org
>
> Signed-off-by: Bing Zhao <bingz@nvidia.com>
Acked-by: Thomas Monjalon <thomas@monjalon.net>
Applied, thanks.
For an unknown reason, our GitHub CI started to fail on Sunday
with Fedora 35. Looks like an update was done in Fedora 35.
Now it is fixed!
@@ -1675,10 +1675,7 @@ mlx5_get_mac(struct rte_eth_dev *dev, uint8_t (*mac)[RTE_ETHER_ADDR_LEN])
*/
int mlx5_get_flag_dropless_rq(struct rte_eth_dev *dev)
{
- struct {
- struct ethtool_sset_info hdr;
- uint32_t buf[1];
- } sset_info;
+ struct ethtool_sset_info *sset_info = NULL;
struct ethtool_drvinfo drvinfo;
struct ifreq ifr;
struct ethtool_gstrings *strings = NULL;
@@ -1689,15 +1686,21 @@ int mlx5_get_flag_dropless_rq(struct rte_eth_dev *dev)
int32_t i;
int ret;
- sset_info.hdr.cmd = ETHTOOL_GSSET_INFO;
- sset_info.hdr.reserved = 0;
- sset_info.hdr.sset_mask = 1ULL << ETH_SS_PRIV_FLAGS;
+ sset_info = mlx5_malloc(0, sizeof(struct ethtool_sset_info) +
+ sizeof(uint32_t), 0, SOCKET_ID_ANY);
+ if (sset_info == NULL) {
+ rte_errno = ENOMEM;
+ return -rte_errno;
+ }
+ sset_info->cmd = ETHTOOL_GSSET_INFO;
+ sset_info->reserved = 0;
+ sset_info->sset_mask = 1ULL << ETH_SS_PRIV_FLAGS;
ifr.ifr_data = (caddr_t)&sset_info;
ret = mlx5_ifreq(dev, SIOCETHTOOL, &ifr);
if (!ret) {
- const uint32_t *sset_lengths = sset_info.hdr.data;
+ const uint32_t *sset_lengths = sset_info->data;
- len = sset_info.hdr.sset_mask ? sset_lengths[0] : 0;
+ len = sset_info->sset_mask ? sset_lengths[0] : 0;
} else if (ret == -EOPNOTSUPP) {
drvinfo.cmd = ETHTOOL_GDRVINFO;
ifr.ifr_data = (caddr_t)&drvinfo;
@@ -1770,5 +1773,6 @@ int mlx5_get_flag_dropless_rq(struct rte_eth_dev *dev)
ret = !!(flags.data & (1U << i));
exit:
mlx5_free(strings);
+ mlx5_free(sset_info);
return ret;
}