[mythtv-commits] Ticket #12395: SSDP thread uses 100% CPU

[MythTV]

#12395: SSDP thread uses 100% CPU
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     Reporter:  Warren Falk <warren@…>  |      Owner:  dblain
         Type:  Bug Report - General    |     Status:  new
     Priority:  minor                   |  Milestone:  unknown
    Component:  MythTV - UPnP           |    Version:  0.27-fixes
     Severity:  medium                  |   Keywords:
Ticket locked:  0                       |
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 On both backend and frontend, the SSDP thread after a few minutes or hours
 will jump to 100% CPU and never come down.

 I discovered this to be caused by a zero byte UDP packet (that some badly
 designed UPNP device on my network must be sending).

 This can be reproduced using the following C program:


 {{{
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <string.h>
 #include <stdio.h>

 int main(int argc, char**argv)
 {
    int sockfd,n;
    struct sockaddr_in servaddr,cliaddr;
    char sendline[0];

    sockfd=socket(AF_INET,SOCK_DGRAM,0);

    bzero(&servaddr,sizeof(servaddr));
    servaddr.sin_family = AF_INET;
    servaddr.sin_addr.s_addr=inet_addr("239.255.255.250");
    servaddr.sin_port=htons(1900);

    int len = 0;
    printf("Send %d bytes\n", len);
    sendto(sockfd,sendline,len,0,(struct sockaddr
 *)&servaddr,sizeof(servaddr));
 }

 }}}

 And then running the following (on the backend, just for example)

 {{{
 top -H -p `pgrep mythbackend`
 }}}

--
Ticket URL: <https://code.mythtv.org/trac/ticket/12395>
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