Re: [PATCH V2 5/5] Tools: hv: kvp: Fix a warning of buffer overflow with gcc 8.0.1

From: Dan Carpenter
Date: Thu Oct 18 2018 - 02:33:09 EST


On Thu, Oct 18, 2018 at 05:09:32AM +0000, kys@xxxxxxxxxxxxxxxxx wrote:
> From: Dexuan Cui <decui@xxxxxxxxxxxxx>
>
> The patch fixes:
>
> hv_kvp_daemon.c: In function 'kvp_set_ip_info':
> hv_kvp_daemon.c:1305:2: note: 'snprintf' output between 41 and 4136 bytes
> into a destination of size 4096
>
> The "(unsigned int)str_len" is to avoid:
>
> hv_kvp_daemon.c:1309:30: warning: comparison of integer expressions of
> different signedness: 'int' and 'long unsigned int' [-Wsign-compare]
>

Ugh... Any tool with the most basic flow analysis would realize this
was a false positive. We use at least three static analyzers which
catch signedness bugs. Can we turn off GCC's warning on this until they
improve it a bit?

regards,
dan carpenter