[v2,1/3] net/tap: fix mbuf double free when writev fails
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Commit Message
From: Yunjian Wang <wangyunjian@huawei.com>
When the tap_write_mbufs() function return with break, mbuf was freed
without incrementing num_packets. This may lead applications also free
the mbuf. And the pmd_tx_burst() function should returns the number of
original packets it actually sent excluding tso mbufs.
Fixes: 9396ad334672 ("net/tap: fix reported number of Tx packets")
CC: stable@dpdk.org
Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
---
drivers/net/tap/rte_eth_tap.c | 21 +++++++++++++++------
1 file changed, 15 insertions(+), 6 deletions(-)
@@ -521,7 +521,7 @@ tap_tx_l3_cksum(char *packet, uint64_t ol_flags, unsigned int l2_len,
}
}
-static inline void
+static inline int
tap_write_mbufs(struct tx_queue *txq, uint16_t num_mbufs,
struct rte_mbuf **pmbufs,
uint16_t *num_packets, unsigned long *num_tx_bytes)
@@ -588,7 +588,7 @@ tap_write_mbufs(struct tx_queue *txq, uint16_t num_mbufs,
seg_len = rte_pktmbuf_data_len(mbuf);
l234_hlen = mbuf->l2_len + mbuf->l3_len + mbuf->l4_len;
if (seg_len < l234_hlen)
- break;
+ return -1;
/* To change checksums, work on a * copy of l2, l3
* headers + l4 pseudo header
@@ -634,10 +634,12 @@ tap_write_mbufs(struct tx_queue *txq, uint16_t num_mbufs,
/* copy the tx frame data */
n = writev(process_private->txq_fds[txq->queue_id], iovecs, j);
if (n <= 0)
- break;
+ return -1;
+
(*num_packets)++;
(*num_tx_bytes) += rte_pktmbuf_pkt_len(mbuf);
}
+ return 0;
}
/* Callback to handle sending packets from the tap interface
@@ -708,8 +710,15 @@ pmd_tx_burst(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
num_mbufs = 1;
}
- tap_write_mbufs(txq, num_mbufs, mbuf,
- &num_packets, &num_tx_bytes);
+ ret = tap_write_mbufs(txq, num_mbufs, mbuf,
+ &num_packets, &num_tx_bytes);
+ if (ret != 0) {
+ txq->stats.errs++;
+ /* free tso mbufs */
+ for (j = 0; j < ret; j++)
+ rte_pktmbuf_free(mbuf[j]);
+ break;
+ }
num_tx++;
/* free original mbuf */
rte_pktmbuf_free(mbuf_in);
@@ -722,7 +731,7 @@ pmd_tx_burst(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
txq->stats.errs += nb_pkts - num_tx;
txq->stats.obytes += num_tx_bytes;
- return num_packets;
+ return num_tx;
}
static const char *