diff options
| author | David Yang <mmyangfl@gmail.com> | 2026-01-14 20:24:45 +0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-01-17 16:22:18 -0800 |
| commit | b47adaab8b3d443868096bac08fdbb3d403194ba (patch) | |
| tree | b88118c99ed77591ad5def57336a503320fad78d /drivers | |
| parent | 6a5e5a3da3557ab1ccc3716b2cdb67aab658dc45 (diff) | |
veth: fix data race in veth_get_ethtool_stats
In veth_get_ethtool_stats(), some statistics protected by
u64_stats_sync, are read and accumulated in ignorance of possible
u64_stats_fetch_retry() events. These statistics, peer_tq_xdp_xmit and
peer_tq_xdp_xmit_err, are already accumulated by veth_xdp_xmit(). Fix
this by reading them into a temporary buffer first.
Fixes: 5fe6e56776ba ("veth: rely on peer veth_rq for ndo_xdp_xmit accounting")
Signed-off-by: David Yang <mmyangfl@gmail.com>
Link: https://patch.msgid.link/20260114122450.227982-1-mmyangfl@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/veth.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/net/veth.c b/drivers/net/veth.c index 14e6f2a2fb77..9982412fd7f2 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -228,16 +228,20 @@ static void veth_get_ethtool_stats(struct net_device *dev, const struct veth_rq_stats *rq_stats = &rcv_priv->rq[i].stats; const void *base = (void *)&rq_stats->vs; unsigned int start, tx_idx = idx; + u64 buf[VETH_TQ_STATS_LEN]; size_t offset; - tx_idx += (i % dev->real_num_tx_queues) * VETH_TQ_STATS_LEN; do { start = u64_stats_fetch_begin(&rq_stats->syncp); for (j = 0; j < VETH_TQ_STATS_LEN; j++) { offset = veth_tq_stats_desc[j].offset; - data[tx_idx + j] += *(u64 *)(base + offset); + buf[j] = *(u64 *)(base + offset); } } while (u64_stats_fetch_retry(&rq_stats->syncp, start)); + + tx_idx += (i % dev->real_num_tx_queues) * VETH_TQ_STATS_LEN; + for (j = 0; j < VETH_TQ_STATS_LEN; j++) + data[tx_idx + j] += buf[j]; } pp_idx = idx + dev->real_num_tx_queues * VETH_TQ_STATS_LEN; |