On Fri, May 29, 2015 at 04:04:05AM -0700, Eric Dumazet wrote:
> On Fri, 2015-05-29 at 13:30 +0300, Vadim Kochan wrote:
> > From: Vadim Kochan <vadi...@gmail.com>
> >
> > Use strdup instead of malloc, and get rid of bad strcpy.
> >
> > Signed-off-by: Vadim Kochan <vadi...@gmail.com>
> > ---
> > misc/ss.c | 3 +--
> > 1 file changed, 1 insertion(+), 2 deletions(-)
> >
> > diff --git a/misc/ss.c b/misc/ss.c
> > index 347e3a1..a719466 100644
> > --- a/misc/ss.c
> > +++ b/misc/ss.c
> > @@ -1908,8 +1908,7 @@ static void tcp_show_info(const struct nlmsghdr *nlh,
> > struct inet_diag_msg *r,
> >
> > if (tb[INET_DIAG_CONG]) {
> > const char *cong_attr =
> > rta_getattr_str(tb[INET_DIAG_CONG]);
> > - s.cong_alg = malloc(strlen(cong_attr + 1));
> > - strcpy(s.cong_alg, cong_attr);
> > + s.cong_alg = strdup(cong_attr);
> > }
> >
> > if (TCPI_HAS_OPT(info, TCPI_OPT_WSCALE)) {
>
> I doubt TCP_CA_NAME_MAX will ever change in the kernel : 16 bytes.
>
> Its typically "cubic" and less than 8 bytes.
>
> Using 8 bytes to point to a malloc(8) is a waste.
>
> Please remove the memory allocation, or store the pointer, since
> tcp_show_info() does the malloc()/free() before return.
>
> diff --git a/misc/ss.c b/misc/ss.c
> index 347e3a1..9fe229f 100644
> --- a/misc/ss.c
> +++ b/misc/ss.c
> @@ -755,7 +755,7 @@ struct tcpstat
> int timer;
> int timeout;
> int probes;
> - char *cong_alg;
> + char cong_alg[16];
> double rto, ato, rtt, rttvar;
> int qack, cwnd, ssthresh, backoff;
> double send_bps;
> @@ -1664,7 +1664,7 @@ static void tcp_stats_print(struct tcpstat *s)
> printf(" ecnseen");
> if (s->has_fastopen_opt)
> printf(" fastopen");
> - if (s->cong_alg)
> + if (s->cong_alg[0])
> printf(" %s", s->cong_alg);
> if (s->has_wscale_opt)
> printf(" wscale:%d,%d", s->snd_wscale, s->rcv_wscale);
> @@ -1906,11 +1906,10 @@ static void tcp_show_info(const struct nlmsghdr *nlh,
> struct inet_diag_msg *r,
> s.has_fastopen_opt = TCPI_HAS_OPT(info,
> TCPI_OPT_SYN_DATA);
> }
>
> - if (tb[INET_DIAG_CONG]) {
> - const char *cong_attr =
> rta_getattr_str(tb[INET_DIAG_CONG]);
> - s.cong_alg = malloc(strlen(cong_attr + 1));
> - strcpy(s.cong_alg, cong_attr);
> - }
> + if (tb[INET_DIAG_CONG])
> + strncpy(s.cong_alg,
> + rta_getattr_str(tb[INET_DIAG_CONG]),
> + sizeof(s.cong_alg) - 1);
>
> if (TCPI_HAS_OPT(info, TCPI_OPT_WSCALE)) {
> s.has_wscale_opt = true;
> @@ -1984,8 +1983,6 @@ static void tcp_show_info(const struct nlmsghdr *nlh,
> struct inet_diag_msg *r,
> tcp_stats_print(&s);
> if (s.dctcp)
> free(s.dctcp);
> - if (s.cong_alg)
> - free(s.cong_alg);
> }
> }
>
>
>
Thanks!
Should I put you in "From" tag or in "Signed-off-by" ?
Or your diff might be used from this email thread ?
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