bin/102226: dhclient stops working, 100% cpu and logs at ~4000 lines/sec

[Joost Bekkers]

The following reply was made to PR bin/102226; it has been noted by GNATS.

From: Joost Bekkers <joost at jodocus.org>
To: Brooks Davis <brooks at one-eyed-alien.net>
Cc: bug-followup at freebsd.org
Subject: Re: bin/102226: dhclient stops working, 100% cpu and logs at ~4000 lines/sec
Date: Mon, 18 Sep 2006 19:05:27 +0200

 I've had dhclient running without problems for 2 weeks now using a single modification:
 
 --- bpf.c.dist  Mon Sep 18 18:55:38 2006
 +++ bpf.c       Mon Sep 18 18:56:46 2006
 @@ -282,7 +282,7 @@
          */
         do {
                 /* If the buffer is empty, fill it. */
 -               if (interface->rbuf_offset == interface->rbuf_len) {
 +               if (interface->rbuf_offset >= interface->rbuf_len) {
                         length = read(interface->rfdesc, interface->rbuf,
                             interface->rbuf_max);
                         if (length <= 0)
 
 
 
 Yesterday I changed back to the original. and the problem occured again.
 (sorry, no tcpdump running at the time)
 
 Sep 17 20:22:15 bps dhclient[13559]: 6927 bad IP checksums seen in 13853 packets
 Sep 17 20:22:15 bps dhclient[13559]: 5 bad IP checksums seen in 5 packets
 Sep 17 20:22:45 bps last message repeated 742794 times
 Sep 17 20:24:46 bps last message repeated 3160822 times
 Sep 17 20:34:47 bps last message repeated 15502818 times
 
 
 gdb(1) got me the following:
 
 (gdb) p *interface
 $1 = {next = 0x0, hw_address = {htype = 1 '\001', hlen = 6 '\006', haddr = "\000`\bZB\t\000\000\000\000\000\000\000\000\000"}, 
   primary_address = {s_addr = 0}, name = "xl0", '\0' <repeats 12 times>, rfdesc = 9, wfdesc = 9, 
   rbuf = 0x8079000 "S\222\rEw\200\006", rbuf_max = 4096, rbuf_offset = 522, rbuf_len = 758, ifp = 0x806c140, client = 0x8072000, 
   noifmedia = 0, errors = 0, dead = 0, index = 1}
 
 interface->rbuf contains the following
 
 00000000  53 92 0d 45 77 80 06 00  68 01 00 00 68 01 00 00  |S..Ew...h...h...|
 00000010  12 00 ff ff ff ff ff ff  00 05 9a d3 f8 21 08 00  |.............!..|
 00000020  45 00 01 5a 5a 62 00 00  ff 11 d6 01 0a 2e 80 01  |E..ZZb..........|
 00000030  ff ff ff ff 00 43 00 44  01 46 00 00 02 01 06 00  |.....C.D.F......|
 00000040  03 98 e8 90 00 00 80 00  00 00 00 00 0a 2e ab bc  |................|
 00000050  d4 8e 27 84 0a 2e 80 01  00 50 94 bc 58 a2 00 00  |..'......P..X...|
 00000060  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
 *
 00000120  00 00 00 00 00 00 00 00  63 82 53 63 35 01 02 36  |........c.Sc5..6|
 00000130  04 d4 8e 27 84 33 04 00  00 0e 10 01 04 ff ff f0  |...'.3..........|
 00000140  00 42 0e 32 31 32 2e 31  34 32 2e 33 39 2e 31 33  |.B.212.142.39.13|
 00000150  32 03 04 0a 2e a0 01 02  04 00 00 0e 10 04 04 d4  |2...............|
 00000160  8e 27 84 07 04 d4 8e 27  84 00 00 00 00 00 00 00  |.'.....'........|
 00000170  00 00 00 00 00 00 00 00  00 ff 00 00 53 92 0d 45  |............S..E|
 00000180  f0 80 06 00 68 01 00 00  68 01 00 00 12 00 ff ff  |....h...h.......|
 00000190  ff ff ff ff 00 05 9a d3  f8 21 08 00 45 00 01 5a  |.........!..E..Z|
 000001a0  5a 63 00 00 ff 11 d6 00  0a 2e 80 01 ff ff ff ff  |Zc..............|
 000001b0  00 43 00 44 01 46 00 00  02 01 06 00 30 61 7f 2b  |.C.D.F......0a.+|
 000001c0  00 00 80 00 00 00 00 00  0a 2e a6 16 d4 8e 27 84  |..............'.|
 000001d0  0a 2e 80 01 00 50 94 bc  5f 86 00 00 00 00 00 00  |.....P.._.......|
 000001e0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
 *
 000002a0  00 00 00 00 63 82 53 63  35 01 02 36 04 d4 8e 27  |....c.Sc5..6...'|
 000002b0  84 33 04 00 00 0e 10 01  04 ff ff f0 00 42 0e 32  |.3...........B.2|
 000002c0  31 32 2e 31 34 32 2e 33  39 2e 31 33 32 03 04 0a  |12.142.39.132...|
 000002d0  2e a0 01 02 04 00 00 0e  10 04 04 d4 8e 27 84 07  |.............'..|
 000002e0  04 d4 8e 27 84 00 00 00  00 00 00 00 00 00 00 00  |...'............|
 000002f0  00 00 00 00 00 ff 63 68  65 6c 6c 6f 2e 6e 6c 1c  |......chello.nl.|
 00000300  04 ff ff ff ff 00 00 00  00 00 00 00 00 00 00 00  |................|
 00000310  00 00 00 00 00 ff 00 00  00 00 00 00 00 00 00 00  |................|
 00000320  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
 00000330  d8 65 f4 44 eb 33 09 00  38 12 03 00 18 03 00 00  |.e.D.3..8.......|
 00000340  6c 6f 30 00 00 00 00 00  00 00 00 00 00 00 00 00  |lo0.............|
 00000350  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
 
 -- 
 greetz Joost
 joost at jodocus.org