Merge tag 'net-pull-request' of https://github.com/jasowang/qemu into staging

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# gpg: Signature made Mon 21 Jul 2025 01:56:45 EDT
# gpg:                using RSA key 215D46F48246689EC77F3562EF04965B398D6211
# gpg: Good signature from "Jason Wang (Jason Wang on RedHat) <jasowang@redhat.com>" [full]
# Primary key fingerprint: 215D 46F4 8246 689E C77F  3562 EF04 965B 398D 6211

* tag 'net-pull-request' of https://github.com/jasowang/qemu:
  net/vhost-user: Remove unused "err" from chr_closed_bh() (CID 1612365)
  net/passt: Initialize "error" variable in net_passt_send() (CID 1612368)
  net/passt: Check return value of g_remove() in net_passt_cleanup() (CID 1612369)
  net/passt: Remove dead code in passt_vhost_user_start error path (CID 1612371)
  net/vhost-user: Remove unused "err" from net_vhost_user_event() (CID 1612372)
  net/passt: Remove unused "err" from passt_vhost_user_event() (CID 1612375)
  hw/net/npcm_gmac.c: Drop 'buf' local variable
  hw/net/npcm_gmac.c: Correct test for when to reallocate packet buffer
  hw/net/npcm_gmac.c: Unify length and prev_buf_size variables
  hw/net/npcm_gmac.c: Send the right data for second packet in a row
  tap: fix net_init_tap() return code
  net/tap: drop too small packets

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

4 files changed, 26 insertions, 40 deletions

diff --git a/hw/net/npcm_gmac.c b/hw/net/npcm_gmac.c
index a434112580..5e32cd3edf 100644
--- a/hw/net/npcm_gmac.c
+++ b/hw/net/npcm_gmac.c
@@ -516,8 +516,6 @@ static void gmac_try_send_next_packet(NPCMGMACState *gmac)
     uint32_t desc_addr;
     struct NPCMGMACTxDesc tx_desc;
     uint32_t tx_buf_addr, tx_buf_len;
-    uint16_t length = 0;
-    uint8_t *buf = tx_send_buffer;
     uint32_t prev_buf_size = 0;
     int csum = 0;
 
@@ -568,22 +566,20 @@ static void gmac_try_send_next_packet(NPCMGMACState *gmac)
         tx_buf_addr = tx_desc.tdes2;
         gmac->regs[R_NPCM_DMA_CUR_TX_BUF_ADDR] = tx_buf_addr;
         tx_buf_len = TX_DESC_TDES1_BFFR1_SZ_MASK(tx_desc.tdes1);
-        buf = &tx_send_buffer[prev_buf_size];
 
-        if ((prev_buf_size + tx_buf_len) > sizeof(buf)) {
+        if ((prev_buf_size + tx_buf_len) > tx_buffer_size) {
             tx_buffer_size = prev_buf_size + tx_buf_len;
             tx_send_buffer = g_realloc(tx_send_buffer, tx_buffer_size);
-            buf = &tx_send_buffer[prev_buf_size];
         }
 
         /* step 5 */
-        if (dma_memory_read(&address_space_memory, tx_buf_addr, buf,
+        if (dma_memory_read(&address_space_memory, tx_buf_addr,
+                            tx_send_buffer + prev_buf_size,
                             tx_buf_len, MEMTXATTRS_UNSPECIFIED)) {
             qemu_log_mask(LOG_GUEST_ERROR, "%s: Failed to read packet @ 0x%x\n",
                         __func__, tx_buf_addr);
             return;
         }
-        length += tx_buf_len;
         prev_buf_size += tx_buf_len;
 
         /* If not chained we'll have a second buffer. */
@@ -591,30 +587,32 @@ static void gmac_try_send_next_packet(NPCMGMACState *gmac)
             tx_buf_addr = tx_desc.tdes3;
             gmac->regs[R_NPCM_DMA_CUR_TX_BUF_ADDR] = tx_buf_addr;
             tx_buf_len = TX_DESC_TDES1_BFFR2_SZ_MASK(tx_desc.tdes1);
-            buf = &tx_send_buffer[prev_buf_size];
 
-            if ((prev_buf_size + tx_buf_len) > sizeof(buf)) {
+            if ((prev_buf_size + tx_buf_len) > tx_buffer_size) {
                 tx_buffer_size = prev_buf_size + tx_buf_len;
                 tx_send_buffer = g_realloc(tx_send_buffer, tx_buffer_size);
-                buf = &tx_send_buffer[prev_buf_size];
             }
 
-            if (dma_memory_read(&address_space_memory, tx_buf_addr, buf,
+            if (dma_memory_read(&address_space_memory, tx_buf_addr,
+                                tx_send_buffer + prev_buf_size,
                                 tx_buf_len, MEMTXATTRS_UNSPECIFIED)) {
                 qemu_log_mask(LOG_GUEST_ERROR,
                               "%s: Failed to read packet @ 0x%x\n",
                               __func__, tx_buf_addr);
                 return;
             }
-            length += tx_buf_len;
             prev_buf_size += tx_buf_len;
         }
         if (tx_desc.tdes1 & TX_DESC_TDES1_LAST_SEG_MASK) {
+            /*
+             * This will truncate the packet at 64K.
+             * TODO: find out if this is the correct behaviour.
+             */
+            uint16_t length = prev_buf_size;
             net_checksum_calculate(tx_send_buffer, length, csum);
             qemu_send_packet(qemu_get_queue(gmac->nic), tx_send_buffer, length);
             trace_npcm_gmac_packet_sent(DEVICE(gmac)->canonical_path, length);
-            buf = tx_send_buffer;
-            length = 0;
+            prev_buf_size = 0;
         }
 
         /* step 6 */
diff --git a/net/passt.c b/net/passt.c
index 6f616ba3c2..32ecffb763 100644
--- a/net/passt.c
+++ b/net/passt.c
@@ -103,7 +103,10 @@ static void net_passt_cleanup(NetClientState *nc)
 #endif
 
     kill(s->pid, SIGTERM);
-    g_remove(s->pidfile);
+    if (g_remove(s->pidfile) != 0) {
+        warn_report("Failed to remove passt pidfile %s: %s",
+                    s->pidfile, strerror(errno));
+    }
     g_free(s->pidfile);
     g_ptr_array_free(s->args, TRUE);
 }
@@ -121,7 +124,7 @@ static gboolean net_passt_send(QIOChannel *ioc, GIOCondition condition,
 {
     if (net_stream_data_send(ioc, condition, data) == G_SOURCE_REMOVE) {
         NetPasstState *s = DO_UPCAST(NetPasstState, data, data);
-        Error *error;
+        Error *error = NULL;
 
         /* we need to restart passt */
         kill(s->pid, SIGTERM);
@@ -375,7 +378,8 @@ static int passt_vhost_user_start(NetPasstState *s, VhostUserState *be)
     net = vhost_net_init(&options);
     if (!net) {
         error_report("failed to init passt vhost_net");
-        goto err;
+        passt_vhost_user_stop(s);
+        return -1;
     }
 
     if (s->vhost_net) {
@@ -385,19 +389,11 @@ static int passt_vhost_user_start(NetPasstState *s, VhostUserState *be)
     s->vhost_net = net;
 
     return 0;
-err:
-    if (net) {
-        vhost_net_cleanup(net);
-        g_free(net);
-    }
-    passt_vhost_user_stop(s);
-    return -1;
 }
 
 static void passt_vhost_user_event(void *opaque, QEMUChrEvent event)
 {
     NetPasstState *s = opaque;
-    Error *err = NULL;
 
     switch (event) {
     case CHR_EVENT_OPENED:
@@ -428,10 +424,6 @@ static void passt_vhost_user_event(void *opaque, QEMUChrEvent event)
         /* Ignore */
         break;
     }
-
-    if (err) {
-        error_report_err(err);
-    }
 }
 
 static int net_passt_vhost_user_init(NetPasstState *s, Error **errp)
diff --git a/net/tap.c b/net/tap.c
index 23536c09b4..f7df702f97 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -190,6 +190,11 @@ static void tap_send(void *opaque)
             break;
         }
 
+        if (s->host_vnet_hdr_len && size <= s->host_vnet_hdr_len) {
+            /* Invalid packet */
+            break;
+        }
+
         if (s->host_vnet_hdr_len && !s->using_vnet_hdr) {
             buf  += s->host_vnet_hdr_len;
             size -= s->host_vnet_hdr_len;
@@ -890,8 +895,8 @@ int net_init_tap(const Netdev *netdev, const char *name,
                 goto free_fail;
             }
 
-            ret = g_unix_set_fd_nonblocking(fd, true, NULL);
-            if (!ret) {
+            if (!g_unix_set_fd_nonblocking(fd, true, NULL)) {
+                ret = -1;
                 error_setg_errno(errp, errno, "%s: Can't use file descriptor %d",
                                  name, fd);
                 goto free_fail;
diff --git a/net/vhost-user.c b/net/vhost-user.c
index 1c3b8b36f3..8b96157145 100644
--- a/net/vhost-user.c
+++ b/net/vhost-user.c
@@ -298,7 +298,6 @@ static void chr_closed_bh(void *opaque)
     const char *name = opaque;
     NetClientState *ncs[MAX_QUEUE_NUM];
     NetVhostUserState *s;
-    Error *err = NULL;
     int queues, i;
 
     queues = qemu_find_net_clients_except(name, ncs,
@@ -317,9 +316,6 @@ static void chr_closed_bh(void *opaque)
     qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, net_vhost_user_event,
                              NULL, opaque, NULL, true);
 
-    if (err) {
-        error_report_err(err);
-    }
     qapi_event_send_netdev_vhost_user_disconnected(name);
 }
 
@@ -329,7 +325,6 @@ static void net_vhost_user_event(void *opaque, QEMUChrEvent event)
     NetClientState *ncs[MAX_QUEUE_NUM];
     NetVhostUserState *s;
     Chardev *chr;
-    Error *err = NULL;
     int queues;
 
     queues = qemu_find_net_clients_except(name, ncs,
@@ -375,10 +370,6 @@ static void net_vhost_user_event(void *opaque, QEMUChrEvent event)
         /* Ignore */
         break;
     }
-
-    if (err) {
-        error_report_err(err);
-    }
 }
 
 static int net_vhost_user_init(NetClientState *peer, const char *device,