[PATCH 15/23] net: Avoid dynamic stack allocation

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

Use autofree heap allocation instead of variable-length
array on the stack.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 hw/net/fsl_etsec/rings.c      | 9 ++++-----
 hw/net/rocker/rocker_of_dpa.c | 2 +-
 net/dump.c                    | 2 +-
 net/tap.c                     | 2 +-
 4 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/hw/net/fsl_etsec/rings.c b/hw/net/fsl_etsec/rings.c
index 8f084464155..1abdcb5a29c 100644
--- a/hw/net/fsl_etsec/rings.c
+++ b/hw/net/fsl_etsec/rings.c
@@ -381,8 +381,6 @@ static void fill_rx_bd(eTSEC          *etsec,
     uint16_t to_write;
     hwaddr   bufptr = bd->bufptr +
         ((hwaddr)(etsec->regs[TBDBPH].value & 0xF) << 32);
-    uint8_t  padd[etsec->rx_padding];
-    uint8_t  rem;
 
     RING_DEBUG("eTSEC fill Rx buffer @ 0x%016" HWADDR_PRIx
                " size:%zu(padding + crc:%u) + fcb:%u\n",
@@ -423,11 +421,12 @@ static void fill_rx_bd(eTSEC          *etsec,
         /* The remaining bytes are only for padding which is not actually
          * allocated in the data buffer.
          */
-
-        rem = MIN(etsec->regs[MRBLR].value - bd->length, etsec->rx_padding);
+        uint8_t  rem = MIN(etsec->regs[MRBLR].value - bd->length,
+                           etsec->rx_padding);
 
         if (rem > 0) {
-            memset(padd, 0x0, sizeof(padd));
+            g_autofree uint8_t *padd = g_malloc0(etsec->rx_padding);
+
             etsec->rx_padding -= rem;
             *size             -= rem;
             bd->length        += rem;
diff --git a/hw/net/rocker/rocker_of_dpa.c b/hw/net/rocker/rocker_of_dpa.c
index b3b8c5bb6d4..3e400ceaef7 100644
--- a/hw/net/rocker/rocker_of_dpa.c
+++ b/hw/net/rocker/rocker_of_dpa.c
@@ -1043,7 +1043,7 @@ static void of_dpa_flow_ig_tbl(OfDpaFlowContext *fc, uint32_t tbl_id)
 static ssize_t of_dpa_ig(World *world, uint32_t pport,
                          const struct iovec *iov, int iovcnt)
 {
-    struct iovec iov_copy[iovcnt + 2];
+    g_autofree struct iovec *iov_copy = g_new(struct iovec, iovcnt + 2);
     OfDpaFlowContext fc = {
         .of_dpa = world_private(world),
         .in_pport = pport,
diff --git a/net/dump.c b/net/dump.c
index 4d538d82a69..b830302e27d 100644
--- a/net/dump.c
+++ b/net/dump.c
@@ -68,7 +68,7 @@ static ssize_t dump_receive_iov(DumpState *s, const struct iovec *iov, int cnt)
     int64_t ts;
     int caplen;
     size_t size = iov_size(iov, cnt);
-    struct iovec dumpiov[cnt + 1];
+    g_autofree struct iovec *dumpiov = g_new(struct iovec, cnt + 1);
 
     /* Early return in case of previous error. */
     if (s->fd < 0) {
diff --git a/net/tap.c b/net/tap.c
index bae895e2874..2b9ed8a2cd8 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -120,7 +120,7 @@ static ssize_t tap_receive_iov(NetClientState *nc, const struct iovec *iov,
 {
     TAPState *s = DO_UPCAST(TAPState, nc, nc);
     const struct iovec *iovp = iov;
-    struct iovec iov_copy[iovcnt + 1];
+    g_autofree struct iovec *iov_copy = g_new(struct iovec, iovcnt + 1);
     struct virtio_net_hdr_mrg_rxbuf hdr = { };
 
     if (s->host_vnet_hdr_len && !s->using_vnet_hdr) {
-- 
2.26.3