[libvirt] [PATCH 1/3] conf: Properly truncate wide character names in virDomainObjGetShortName

Martin Kletzander mkletzan at redhat.com
Wed Aug 23 11:47:26 UTC 2017 

We always truncated the name at 20 bytes instead of characters.  In
case 20 bytes were in the middle of a multi-byte character, then the
string became invalid and various parts of the code would error
out (e.g. XML parsing of that string).  Let's instead properly
truncate it after 20 characters instead.

In some cases the truncation didn't even work (as can be seen from the
modified tests), which is fixed by this as well.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1448766

Signed-off-by: Martin Kletzander <mkletzan at redhat.com>
---
 src/conf/domain_conf.c                             | 30 +++++++++++++++++++---
 .../qemuxml2argv-aarch64-virt-default-nic.args     |  2 +-
 .../qemuxml2argv-hugepages-pages2.args             |  4 +--
 .../qemuxml2argv-hugepages-pages3.args             |  5 ++--
 .../qemuxml2argv-hugepages-pages5.args             |  4 +--
 .../qemuxml2argv-hugepages-pages6.args             |  2 +-
 .../qemuxml2argv-pcie-expander-bus.args            |  2 +-
 7 files changed, 37 insertions(+), 12 deletions(-)

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 47eba4dbb315..9a46ceece2d6 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -27131,6 +27131,8 @@ virDomainDefHasMemballoon(const virDomainDef *def)
 }
 
 
+#define VIR_DOMAIN_SHORT_NAME_MAX 20
+
 /**
  * virDomainObjGetShortName:
  * @vm: Machine for which to get a name
@@ -27141,15 +27143,37 @@ virDomainDefHasMemballoon(const virDomainDef *def)
 char *
 virDomainObjGetShortName(const virDomainDef *def)
 {
-    const int dommaxlen = 20;
+    wchar_t wshortname[VIR_DOMAIN_SHORT_NAME_MAX + 1] = {0};
+    size_t len = 0;
+    char *shortname = NULL;
     char *ret = NULL;
 
-    ignore_value(virAsprintf(&ret, "%d-%.*s",
-                             def->id, dommaxlen, def->name));
+    if (mbstowcs(wshortname, def->name, VIR_DOMAIN_SHORT_NAME_MAX) == (size_t) -1) {
+        virReportError(VIR_ERR_INVALID_ARG, "%s",
+                       _("Cannot convert domain name to wide character string"));
+        return NULL;
+    }
+
+    len = wcstombs(NULL, wshortname, 0);
+    if (len == (size_t) -1)
+        return NULL;
 
+    if (VIR_ALLOC_N(shortname, len + 1) < 0)
+        return NULL;
+
+    if (wcstombs(shortname, wshortname, len) == (size_t) -1) {
+        virReportError(VIR_ERR_INVALID_ARG, "%s",
+                       _("Cannot convert domain name from wide character string"));
+        goto cleanup;
+    }
+
+    ignore_value(virAsprintf(&ret, "%d-%s", def->id, def->name));
+ cleanup:
+    VIR_FREE(shortname);
     return ret;
 }
 
+#undef VIR_DOMAIN_SHORT_NAME_MAX
 
 int
 virDomainGetBlkioParametersAssignFromDef(virDomainDefPtr def,
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-aarch64-virt-default-nic.args b/tests/qemuxml2argvdata/qemuxml2argv-aarch64-virt-default-nic.args
index f27fe0a1d364..08930df8a218 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-aarch64-virt-default-nic.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-aarch64-virt-default-nic.args
@@ -16,7 +16,7 @@ QEMU_AUDIO_DRV=none \
 -nodefconfig \
 -nodefaults \
 -chardev socket,id=charmonitor,\
-path=/tmp/lib/domain--1-aarch64-virt-default/monitor.sock,server,nowait \
+path=/tmp/lib/domain--1-aarch64-virt-default-nic/monitor.sock,server,nowait \
 -mon chardev=charmonitor,id=monitor,mode=readline \
 -no-acpi \
 -boot c \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages2.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages2.args
index 7ea277a7cd65..ab0eb7ff0ca3 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages2.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages2.args
@@ -11,14 +11,14 @@ QEMU_AUDIO_DRV=none \
 -m 1024 \
 -smp 2,sockets=2,cores=1,threads=1 \
 -mem-prealloc \
--mem-path /dev/hugepages2M/libvirt/qemu/-1-SomeDummyHugepagesGu \
+-mem-path /dev/hugepages2M/libvirt/qemu/-1-SomeDummyHugepagesGuest \
 -numa node,nodeid=0,cpus=0,mem=256 \
 -numa node,nodeid=1,cpus=1,mem=768 \
 -uuid ef1bdff4-27f3-4e85-a807-5fb4d58463cc \
 -nographic \
 -nodefaults \
 -chardev socket,id=charmonitor,\
-path=/tmp/lib/domain--1-SomeDummyHugepagesGu/monitor.sock,server,nowait \
+path=/tmp/lib/domain--1-SomeDummyHugepagesGuest/monitor.sock,server,nowait \
 -mon chardev=charmonitor,id=monitor,mode=readline \
 -no-acpi \
 -boot c \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages3.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages3.args
index 2291d6d72e8a..4794a940b1b3 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages3.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages3.args
@@ -13,13 +13,14 @@ QEMU_AUDIO_DRV=none \
 -object memory-backend-ram,id=ram-node0,size=268435456 \
 -numa node,nodeid=0,cpus=0,memdev=ram-node0 \
 -object memory-backend-file,id=ram-node1,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu/-1-SomeDummyHugepagesGu,size=805306368 \
+mem-path=/dev/hugepages1G/libvirt/qemu/-1-SomeDummyHugepagesGuest,\
+size=805306368 \
 -numa node,nodeid=1,cpus=1,memdev=ram-node1 \
 -uuid ef1bdff4-27f3-4e85-a807-5fb4d58463cc \
 -nographic \
 -nodefaults \
 -chardev socket,id=charmonitor,\
-path=/tmp/lib/domain--1-SomeDummyHugepagesGu/monitor.sock,server,nowait \
+path=/tmp/lib/domain--1-SomeDummyHugepagesGuest/monitor.sock,server,nowait \
 -mon chardev=charmonitor,id=monitor,mode=readline \
 -no-acpi \
 -boot c \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages5.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages5.args
index c5bf7784ec23..124dd578f390 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages5.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages5.args
@@ -10,13 +10,13 @@ QEMU_AUDIO_DRV=none \
 -M pc \
 -m 1024 \
 -mem-prealloc \
--mem-path /dev/hugepages2M/libvirt/qemu/-1-SomeDummyHugepagesGu \
+-mem-path /dev/hugepages2M/libvirt/qemu/-1-SomeDummyHugepagesGuest \
 -smp 2,sockets=2,cores=1,threads=1 \
 -uuid ef1bdff4-27f3-4e85-a807-5fb4d58463cc \
 -nographic \
 -nodefaults \
 -chardev socket,id=charmonitor,\
-path=/tmp/lib/domain--1-SomeDummyHugepagesGu/monitor.sock,server,nowait \
+path=/tmp/lib/domain--1-SomeDummyHugepagesGuest/monitor.sock,server,nowait \
 -mon chardev=charmonitor,id=monitor,mode=readline \
 -no-acpi \
 -boot c \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages6.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages6.args
index c1cc0017f335..31a17db44994 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages6.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages6.args
@@ -14,7 +14,7 @@ QEMU_AUDIO_DRV=none \
 -nographic \
 -nodefaults \
 -chardev socket,id=charmonitor,\
-path=/tmp/lib/domain--1-SomeDummyHugepagesGu/monitor.sock,server,nowait \
+path=/tmp/lib/domain--1-SomeDummyHugepagesGuest/monitor.sock,server,nowait \
 -mon chardev=charmonitor,id=monitor,mode=readline \
 -no-acpi \
 -boot c \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-pcie-expander-bus.args b/tests/qemuxml2argvdata/qemuxml2argv-pcie-expander-bus.args
index 23852b45e56a..f42a69fc3fd1 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-pcie-expander-bus.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-pcie-expander-bus.args
@@ -16,7 +16,7 @@ QEMU_AUDIO_DRV=none \
 -nographic \
 -nodefaults \
 -chardev socket,id=charmonitor,\
-path=/tmp/lib/domain--1-pcie-expander-bus-te/monitor.sock,server,nowait \
+path=/tmp/lib/domain--1-pcie-expander-bus-test/monitor.sock,server,nowait \
 -mon chardev=charmonitor,id=monitor,mode=readline \
 -no-acpi \
 -boot c \
-- 
2.14.1

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