Jim Meyering <jim@meyering.net> wrote on 03/29/2010 01:22:56 PM:
[image removed]
Re: [libvirt] [PATCH] nwfilter_ebiptables_driver.c: avoid NULL dereference
Jim Meyering
to:
Eric Blake
03/29/2010 01:23 PM
Cc:
Stefan Berger, Libvirt
Eric Blake wrote:
On 03/29/2010 10:37 AM, Jim Meyering wrote:
Another one caught by clang:
Note the first test to see if "inst" may be NULL. Then, in the following loop, "inst" is unconditionally dereferenced via "inst[i]". There are other unprotected used of "inst[i]" below, too.
Rather than trying to protect all uses, one by one, I chose to return "success" when given an empty list of rules.
ACK that your patch is the minimal fix to avoid a segfault, but we should probably get Stefan's input on whether returning success on an empty input is the best course of behavior.
Ok. I've Cc'd him.
Actually the inst[n] accesses are protected by nInstances having to be > 0 for code to try to read a inst[n]. So it should be fine the way it is. nInstances and inst belong together and nInstances indicates the number of members in that array. No member of inst[] is expected to be NULL. Stefan