From 9085bbfb415baa258f58e79c56454a520c03d91f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= <berrange@redhat.com>
Date: Fri, 15 Mar 2024 10:47:50 +0000
Subject: [PATCH] remote: check for negative array lengths before allocation
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While the C API entry points will validate non-negative lengths
for various parameters, the RPC server de-serialization code
will need to allocate memory for arrays before entering the C
API. These allocations will thus happen before the non-negative
length check is performed.

Passing a negative length to the g_new0 function will usually
result in a crash due to the negative length being treated as
a huge positive number.

This was found and diagnosed by ALT Linux Team with AFLplusplus.

CVE-2024-2494
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Found-by: Alexandr Shashkin <dutyrok@altlinux.org>
Co-developed-by: Alexander Kuznetsov <kuznetsovam@altlinux.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 src/remote/remote_daemon_dispatch.c | 65 +++++++++++++++++++++++++++++
 src/rpc/gendispatch.pl              |  5 +++
 2 files changed, 70 insertions(+)

diff --git a/src/remote/remote_daemon_dispatch.c b/src/remote/remote_daemon_dispatch.c
index 7daf503b51..7542caa952 100644
--- a/src/remote/remote_daemon_dispatch.c
+++ b/src/remote/remote_daemon_dispatch.c
@@ -2291,6 +2291,10 @@ remoteDispatchDomainGetSchedulerParameters(virNetServer *server G_GNUC_UNUSED,
     if (!conn)
         goto cleanup;
 
+    if (args->nparams < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams must be non-negative"));
+        goto cleanup;
+    }
     if (args->nparams > REMOTE_DOMAIN_SCHEDULER_PARAMETERS_MAX) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams too large"));
         goto cleanup;
@@ -2339,6 +2343,10 @@ remoteDispatchDomainGetSchedulerParametersFlags(virNetServer *server G_GNUC_UNUS
     if (!conn)
         goto cleanup;
 
+    if (args->nparams < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams must be non-negative"));
+        goto cleanup;
+    }
     if (args->nparams > REMOTE_DOMAIN_SCHEDULER_PARAMETERS_MAX) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams too large"));
         goto cleanup;
@@ -2497,6 +2505,10 @@ remoteDispatchDomainBlockStatsFlags(virNetServer *server G_GNUC_UNUSED,
         goto cleanup;
     flags = args->flags;
 
+    if (args->nparams < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams must be non-negative"));
+        goto cleanup;
+    }
     if (args->nparams > REMOTE_DOMAIN_BLOCK_STATS_PARAMETERS_MAX) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams too large"));
         goto cleanup;
@@ -2717,6 +2729,14 @@ remoteDispatchDomainGetVcpuPinInfo(virNetServer *server G_GNUC_UNUSED,
     if (!(dom = get_nonnull_domain(conn, args->dom)))
         goto cleanup;
 
+    if (args->ncpumaps < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("ncpumaps must be non-negative"));
+        goto cleanup;
+    }
+    if (args->maplen < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("maplen must be non-negative"));
+        goto cleanup;
+    }
     if (args->ncpumaps > REMOTE_VCPUINFO_MAX) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("ncpumaps > REMOTE_VCPUINFO_MAX"));
         goto cleanup;
@@ -2811,6 +2831,11 @@ remoteDispatchDomainGetEmulatorPinInfo(virNetServer *server G_GNUC_UNUSED,
     if (!(dom = get_nonnull_domain(conn, args->dom)))
         goto cleanup;
 
+    if (args->maplen < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("maplen must be non-negative"));
+        goto cleanup;
+    }
+
     /* Allocate buffers to take the results */
     if (args->maplen > 0)
         cpumaps = g_new0(unsigned char, args->maplen);
@@ -2858,6 +2883,14 @@ remoteDispatchDomainGetVcpus(virNetServer *server G_GNUC_UNUSED,
     if (!(dom = get_nonnull_domain(conn, args->dom)))
         goto cleanup;
 
+    if (args->maxinfo < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("maxinfo must be non-negative"));
+        goto cleanup;
+    }
+    if (args->maplen < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("maxinfo must be non-negative"));
+        goto cleanup;
+    }
     if (args->maxinfo > REMOTE_VCPUINFO_MAX) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("maxinfo > REMOTE_VCPUINFO_MAX"));
         goto cleanup;
@@ -3096,6 +3129,10 @@ remoteDispatchDomainGetMemoryParameters(virNetServer *server G_GNUC_UNUSED,
 
     flags = args->flags;
 
+    if (args->nparams < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams must be non-negative"));
+        goto cleanup;
+    }
     if (args->nparams > REMOTE_DOMAIN_MEMORY_PARAMETERS_MAX) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams too large"));
         goto cleanup;
@@ -3156,6 +3193,10 @@ remoteDispatchDomainGetNumaParameters(virNetServer *server G_GNUC_UNUSED,
 
     flags = args->flags;
 
+    if (args->nparams < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams must be non-negative"));
+        goto cleanup;
+    }
     if (args->nparams > REMOTE_DOMAIN_NUMA_PARAMETERS_MAX) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams too large"));
         goto cleanup;
@@ -3216,6 +3257,10 @@ remoteDispatchDomainGetBlkioParameters(virNetServer *server G_GNUC_UNUSED,
 
     flags = args->flags;
 
+    if (args->nparams < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams must be non-negative"));
+        goto cleanup;
+    }
     if (args->nparams > REMOTE_DOMAIN_BLKIO_PARAMETERS_MAX) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams too large"));
         goto cleanup;
@@ -3277,6 +3322,10 @@ remoteDispatchNodeGetCPUStats(virNetServer *server G_GNUC_UNUSED,
 
     flags = args->flags;
 
+    if (args->nparams < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams must be non-negative"));
+        goto cleanup;
+    }
     if (args->nparams > REMOTE_NODE_CPU_STATS_MAX) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams too large"));
         goto cleanup;
@@ -3339,6 +3388,10 @@ remoteDispatchNodeGetMemoryStats(virNetServer *server G_GNUC_UNUSED,
 
     flags = args->flags;
 
+    if (args->nparams < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams must be non-negative"));
+        goto cleanup;
+    }
     if (args->nparams > REMOTE_NODE_MEMORY_STATS_MAX) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams too large"));
         goto cleanup;
@@ -3514,6 +3567,10 @@ remoteDispatchDomainGetBlockIoTune(virNetServer *server G_GNUC_UNUSED,
     if (!conn)
         goto cleanup;
 
+    if (args->nparams < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams must be non-negative"));
+        goto cleanup;
+    }
     if (args->nparams > REMOTE_DOMAIN_BLOCK_IO_TUNE_PARAMETERS_MAX) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams too large"));
         goto cleanup;
@@ -5079,6 +5136,10 @@ remoteDispatchDomainGetInterfaceParameters(virNetServer *server G_GNUC_UNUSED,
 
     flags = args->flags;
 
+    if (args->nparams < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams must be non-negative"));
+        goto cleanup;
+    }
     if (args->nparams > REMOTE_DOMAIN_INTERFACE_PARAMETERS_MAX) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams too large"));
         goto cleanup;
@@ -5299,6 +5360,10 @@ remoteDispatchNodeGetMemoryParameters(virNetServer *server G_GNUC_UNUSED,
 
     flags = args->flags;
 
+    if (args->nparams < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams must be non-negative"));
+        goto cleanup;
+    }
     if (args->nparams > REMOTE_NODE_MEMORY_PARAMETERS_MAX) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("nparams too large"));
         goto cleanup;
diff --git a/src/rpc/gendispatch.pl b/src/rpc/gendispatch.pl
index 5ce988c5ae..c5842dc796 100755
--- a/src/rpc/gendispatch.pl
+++ b/src/rpc/gendispatch.pl
@@ -1070,6 +1070,11 @@ elsif ($mode eq "server") {
         print "\n";
 
         if ($single_ret_as_list) {
+            print "    if (args->$single_ret_list_max_var < 0) {\n";
+            print "        virReportError(VIR_ERR_RPC,\n";
+            print "                       \"%s\", _(\"max$single_ret_list_name must be non-negative\"));\n";
+            print "        goto cleanup;\n";
+            print "    }\n";
             print "    if (args->$single_ret_list_max_var > $single_ret_list_max_define) {\n";
             print "        virReportError(VIR_ERR_RPC,\n";
             print "                       \"%s\", _(\"max$single_ret_list_name > $single_ret_list_max_define\"));\n";
-- 
2.27.0

