[U-Boot] [PATCH] net: bootp: Ignore packets whose yiaddr is 0
Wolfgang Denk
wd at denx.de
Thu Jan 7 00:49:42 CET 2016
Dear Peng Fan,
In message <1451875796-15860-1-git-send-email-peng.fan at nxp.com> you wrote:
> When doing `dhcp`, there is a bad dhcp server in my network
> which always reply dhcp request with yiaddr 0, which cause
> uboot can not successfully get ipaddr from the good dhcp server.
> But the Linux PC can get the ip address even if there is a bad
> dhcp server. This patch is to fix that even if there is a bad
> dhcp server, uboot can still get ipaddr and tftp work ok.
>
> The way is to ignore the packets from the bad dhcp server by filtering
> out the yiaddr whose value is 0.
>
> Signed-off-by: Peng Fan <peng.fan at nxp.com>
> Cc: Joe Hershberger <joe.hershberger at ni.com>
> ---
> net/bootp.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/net/bootp.c b/net/bootp.c
> index 8aeddb0..ff2ebbe 100644
> --- a/net/bootp.c
> +++ b/net/bootp.c
> @@ -992,6 +992,9 @@ static void dhcp_handler(uchar *pkt, unsigned dest, struct in_addr sip,
> if (check_reply_packet(pkt, dest, src, len))
> return;
>
> + if (net_read_ip(&bp->bp_yiaddr).s_addr == 0)
> + return;
> +
> debug("DHCPHandler: got DHCP packet: (src=%d, dst=%d, len=%d) state: "
> "%d\n", src, dest, len, dhcp_state);
I suggest the return should be done _after_ the debug message.
Best regards,
Wolfgang Denk
--
DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
The human race is a race of cowards; and I am not only marching in
that procession but carrying a banner. - Mark Twain
More information about the U-Boot
mailing list