Re: [libvirt] [PATCH] virsh: avoid uninitialized memory usage

At 04/19/2012 04:09 PM, Alex Jia Wrote: > Detected by valgrind. > > * tools/virsh.c (cmdBlockPull): fix uninitialized memory usage. > > * How to reproduce? > $ qemu-img create /var/lib/libvirt/images/test 1M > $ cat> /tmp/test.xml<<EOF > <domain type='qemu'> > <name>test</name> > <memory>219200</memory> > <vcpu>1</vcpu> > <os> > <type arch='x86_64'>hvm</type> > <boot dev='hd'/> > </os> > <devices> > <disk type='file' device='disk'> > <driver name='qemu' type='raw'/> > <source file='/var/lib/libvirt/images/test'/> > <target dev='vda' bus='virtio'/> > </disk> > <input type='mouse' bus='ps2'/> > <graphics type='spice' autoport='yes' listen='0.0.0.0'/> > </devices> > </domain> > EOF > $ virsh define /tmp/test.xml > $ valgrind -v virsh blockpull test /var/lib/libvirt/images/test --wait > > actual result: > > ==10906== 1 errors in context 1 of 1: > ==10906== Syscall param rt_sigaction(act->sa_flags) points to uninitialised byte(s) > ==10906== at 0x39CF80F5BE: __libc_sigaction (sigaction.c:67) > ==10906== by 0x43016C: cmdBlockPull (virsh.c:7638) > ==10906== by 0x4150D4: vshCommandRun (virsh.c:18574) > ==10906== by 0x425E73: main (virsh.c:20178) > ==10906== Address 0x7fefffae8 is on thread 1's stack > > > Signed-off-by: Alex Jia&lt;ajia(a)redhat.com&gt; > --- > tools/virsh.c | 1 + > 1 files changed, 1 insertions(+), 0 deletions(-) > > diff --git a/tools/virsh.c b/tools/virsh.c > index 95ed7bc..4e4ca57 100644 > --- a/tools/virsh.c > +++ b/tools/virsh.c > @@ -7634,6 +7634,7 @@ cmdBlockPull(vshControl *ctl, const vshCmd *cmd) > > intCaught = 0; > sig_action.sa_sigaction = vshCatchInt; > + sigemptyset((sigset_t *)&sig_action.sa_flags); Why using sigemptyset here? You should use 'sig_action.sa_flags = 0'.

Thanks Wen Congyang > sigemptyset(&sig_action.sa_mask); > sigaction(SIGINT,&sig_action,&old_sig_action); >