Re: [PATCH 2/4] util: fix virSocketAddrMask() when source and result are the same object

Many years ago (2011), virSocketAddrMask() had caused a bug by failing to initialize an IPv6-specific field in the result virSocketAddr. This was fixed by memset(0)ing the entire result (*network) at the beginning of the function (thus making sure anything and everything was initialized). The problem is that virSocketAddrMask() has a comment above it that says that the source (addr) and destination (network) arguments can point to the same virSocketAddr. But in that case, the memset(*network, 0) at the top of the function is actually doing a memset(*addr, 0), and so there is nothing left for all the assignments to copy except a giant field of 0's. Fortunately in the 13 years since the memset was added, nobody has ever called virSocketAddrMask() with addr and network being the same.

This patch makes the code agree with the comment by copying/masking into a local virSocketAddr (which is initialized to all 0!) and then

copying that to *network after it's finished assigning things from addr. Fixes: ba08c5932e556aa4f5101357127a6224c40e5ebe Signed-off-by: Laine Stump <laine(a)redhat.com&gt; --- src/util/virsocketaddr.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-)