Re: [dpdk-stable] [PATCH v3 1/1] fbarray: get fbarrays from containerized secondary

["Burakov, Anatoly" <anatoly.burakov@intel.com>]

On 22-Jul-19 2:06 AM, Ogawa Yasufumi wrote:
> 
> 
> 2019年7月12日(金) 11:22 Yasufumi Ogawa <yasufum.o@gmail.com 
> <mailto:yasufum.o@gmail.com>>:
> 
>     On 2019/07/11 22:14, Burakov, Anatoly wrote:
>      > On 11-Jul-19 12:57 PM, Yasufumi Ogawa wrote:
>      >> On 2019/07/11 19:53, Burakov, Anatoly wrote:
>      >>> On 11-Jul-19 11:31 AM, yasufum.o@gmail.com
>     <mailto:yasufum.o@gmail.com> wrote:
>      >>>> From: Yasufumi Ogawa <ogawa.yasufumi@lab.ntt.co.jp
>     <mailto:ogawa.yasufumi@lab.ntt.co.jp>>
>      >>>>
>      >>> <...>
>      >>>
>      >>>> +    if (getpid() == 1) {
>      >>>> +        FILE *hn_fp;
>      >>>> +        hn_fp = fopen("/etc/hostname", "r");
>      >>>> +        if (hn_fp == NULL) {
>      >>>> +            RTE_LOG(ERR, EAL,
>      >>>> +                "Cannot open '/etc/hostname' for secondary\n");
>      >>>> +            return -1;
>      >>>> +        }
>      >>>> +
>      >>>> +        /* with docker, /etc/hostname just has one entry of
>      >>>> hostname */
>      >>>> +        if (fscanf(hn_fp, "%s", proc_id) == EOF) {
>      >>>
>      >>> Apologies for not pointing this out earlier, but do i understand
>      >>> correctly that there's no bounds checking here, and fscanf() will
>      >>> write however many bytes it wants?
>      >> I understand "%s" is not appropriate. hostname is 12 bytes char
>     and I
>      >> thought proc_id[16] is enough, but it is unsafe. In addition,
>     hostname
>      >> can be defined by user with docker's option, so it should be enough
>      >> for user defined name.
>      >>
>      >> How do you think expecting max 32 chars of hostname and set
>     boundary
>      >> "%32s" as following?
>      >>
>      >>      proc_id[33];  /* define proc id from hostname less than 33
>     bytes. */
>      >>      ...
>      >>      if (fscanf(hn_fp, "%32s", proc_id) == EOF) {
>      >>
>      >
>      > As long as it takes NULL-termination into account as well, it
>     should be
>      > OK. I can't recall off the top of my head if %32s includes NULL
>      > terminator (probably not?).
>     Do you agree if initialize with NULL chars to ensure proc_id is
>     NULL-terminated? As tested on my environment, "%Ns" sets next of Nth
>     char as NULL, but it seems more reliable.
>           proc_id[33] = { 0 };
> 
> Hi Anatoly,
> 
> I would like to send v4 patch if it is agreeable.

Yes, please do.

As a side note, you don't need to ask anyone's permission to send a patch :)

> 
> 
>     Yasufumi
> 


-- 
Thanks,
Anatoly