H/2 code crashes if you specify a low-ish SETTINGS_INITIAL_WINDOW_SIZE

[daghf]

varnishd command line:

  $ bin/varnishd/varnishd -a :9090 -b localhost:8080 -n /tmp/foo -d

Request sent via nghttp command line

  $ nghttp http://localhost:9090/ -n -v --no-dep -w 7

where -w 7 sets SETTINGS_INITIAL_WINDOW_SIZE to 127.

Error: Child (9226) died signal=6
Error: Child (9226) Panic at: Wed, 31 Aug 2016 09:08:38 GMT
"Missing errorhandling code in h2_rxframe(), http2/cache_http2_proto.c line 514:
  Condition(h2->rxf_stream > h2->highest_stream) not true.thread = (cache-worker)
version = varnish-trunk revision e7b05d7
ident = Linux,4.6.0-1-amd64,x86_64,-jnone,-smalloc,-smalloc,-hcritbit,epoll
Backtrace:
  0x4521b0: pan_backtrace+0x20
  0x451fd3: pan_ic+0x363
  0x49af6b: h2_rxframe+0x28b
  0x49a029: h2_new_session+0x489
  0x47fe95: Pool_Work_Thread+0x675
  0x47f6d4: WRK_Thread+0x324
  0x47f37d: pool_thread+0xdd
  0x7f3a26a14464: libpthread.so.0(+0x7464) [0x7f3a26a14464]
  0x7f3a2675330d: libc.so.6(clone+0x6d) [0x7f3a2675330d]
req = 0x7f3a14cf6020 {
  vxid = 65541, transport = H2
  step = 0x0,
  req_body = R_BODY_INIT,
  err_code = 1, err_reason = (null),
  restarts = 0, esi_level = 0,
  sp = 0x7f3a1480f820 {
    fd = 26, vxid = 65541,
    t_open = 1472634518.353233,
    t_idle = 1472634518.353824,
    transport = H2 {
      streams {
        0x00000000 idle  
      }
    }
client = ::1 53890,
  },
  ws = 0x7f3a14cf61f8 {
    id = \"req\",
    {s, f, r, e} = {0x7f3a14cf7ff8, +288, (nil), +57344},
  },
  http_conn = 0x7f3a14cf6128 {
    fd = 26,
    doclose = NULL,
    ws = 0x7f3a1b1eae78,
    {rxbuf_b, rxbuf_e} = {0x7f3a1b1ea470, 0x7f3a1b1ea48e},
    {pipeline_b, pipeline_e} = {0x7f3a1b1ea47d, 0x7f3a1b1ea48e},
    content_length = 0,
    body_status = none,
    first_byte_timeout = 0.000000,
    between_bytes_timeout = 0.000000,
  },
  http[req] = 0x7f3a14cf6290 {
    ws[] = (nil),
    hdrs {
    },
  },
  flags = {
  },
},

"

[nigoroll]

Also occurred here https://travis-ci.org/varnishcache/varnish-cache/jobs/157804082 in t2000.vtc

**** v1    0.5 vsl|          0 CLI             - Rd debug.listen_address 
**** v1    0.5 vsl|          0 CLI             - Wr 200 16 127.0.0.1 60805
**** v1    0.5 vsl|       1000 Begin           c sess 0 HTTP/1
**** v1    0.5 vsl|       1000 SessOpen        c 127.0.0.1 41890 127.0.0.1:60805 127.0.0.1 60805 1473145329.761188 20
**** v1    0.5 vsl|          0 Debug           - H2 Prior Knowledge Upgrade
**** v1    0.5 vsl|       1000 Debug           c H2: Got pu PRISM
**** v1    0.5 vsl|          0 Debug           - RX 0x2ab6b058a3f0 9 0
**** v1    0.5 vsl|       1000 H2TxHdr         c 00000c040000000000
**** v1    0.5 vsl|       1000 H2TxBody        c 00030000006400040000ffff
**** v1    0.5 vsl|       1000 H2RxHdr         c 000000040000000000
**** v1    0.5 vsl|       1000 Debug           c H2RXF SETTINGS[0] 0x00 0x00000000
**** v1    0.5 vsl|          0 Debug           - RX 0x2ab6b058a3f0 9 0
**** v1    0.5 vsl|       1000 H2TxHdr         c 000000040100000000
**** v1    0.5 vsl|       1000 H2RxHdr         c 000000040100000000
**** v1    0.5 vsl|       1000 Debug           c H2RXF SETTINGS[0] 0x01 0x00000000
**** v1    0.6 vsl|          0 Debug           - RX 0x2ab6b058a3f0 107 56
**** v1    0.6 vsl|       1000 H2RxHdr         c 000038010500000007
**** v1    0.6 vsl|       1000 H2RxBody        c 000a3a617574686f7269747907666f6f2e62617200053a70617468012f00073a6d6574686f640347455400073a736368656d650468747470
**** v1    0.6 vsl|       1000 Debug           c H2RXF HEADERS[56] 0x05 0x00000007 0x000a3a617574686f7269747907666f6f2e62617200053a70617468012f00073a6d6574686f640347455400073a736368656d650468747470
**** v1    0.6 vsl|       1001 Begin           c req 1000 rxreq
**** v1    0.6 vsl|       1000 Link            c req 1001 rxreq
**** v1    0.6 vsl|       1001 Timestamp       c Start: 1473145329.800956 0.000000 0.000000
**** v1    0.6 vsl|       1001 Timestamp       c Req: 1473145329.800957 0.000000 0.000000
**** v1    0.6 vsl|       1001 ReqProtocol     c HTTP/2.0
**** v1    0.6 vsl|          0 Debug           - RX 0x2ab6b058a3f0 42 5
***  v1    0.7 debug| Error: Child (58534) died signal=6 (core dumped)\n
***  v1    0.7 debug| Error: Child (58534) Panic at: Tue, 06 Sep 2016 07:02:09 GMT\n
***  v1    0.7 debug| "Missing errorhandling code in h2_rxframe(), http2/cache_http2_proto.c line 521:\n
***  v1    0.7 debug|   Condition(h2->rxf_stream > h2->highest_stream) not true.thread = (cache-worker)\n
***  v1    0.7 debug| version = varnish-trunk revision eabda64\n
***  v1    0.7 debug| ident = Linux,3.13.0-40-generic,x86_64,-jnone,-smalloc,-smalloc,-hcritbit,epoll\n
***  v1    0.7 debug| Backtrace:\n
***  v1    0.7 debug|   0x4358c1: pan_ic+0x151\n
***  v1    0.7 debug|   0x45cd3a: h2_new_session+0xe3a\n
***  v1    0.7 debug|   0x44d2ea: WRK_Thread+0x49a\n
***  v1    0.7 debug|   0x44d73b: pool_thread+0x2b\n
***  v1    0.7 debug|   0x2ab6b13abe9a: libpthread.so.0(+0x7e9a) [0x2ab6b13abe9a]\n
***  v1    0.7 debug|   0x2ab6b16b436d: libc.so.6(clone+0x6d) [0x2ab6b16b436d]\n
***  v1    0.7 debug| req = 0x2ab6d8050930 {\n
***  v1    0.7 debug|   vxid = 1000, transport = H2\n
***  v1    0.7 debug|   step = 0x0,\n
***  v1    0.7 debug|   req_body = R_BODY_INIT,\n
***  v1    0.7 debug|   err_code = 1, err_reason = (null),\n
***  v1    0.7 debug|   restarts = 0, esi_level = 0,\n
***  v1    0.7 debug|   sp = 0x2ab6d4001330 {\n
***  v1    0.7 debug|     fd = 20, vxid = 1000,\n
***  v1    0.7 debug|     t_open = 1473145329.761188,\n
***  v1    0.7 debug|     t_idle = 1473145329.800996,\n
***  v1    0.7 debug|     transport = H2 {\n
***  v1    0.7 debug|       streams {\n
***  v1    0.7 debug|         0x00000000 idle  \n
***  v1    0.7 debug|         0x00000007 idle  \n
***  v1    0.7 debug|       }\n
***  v1    0.7 debug|     }\n
***  v1    0.7 debug| client = 127.0.0.1 41890,\n
***  v1    0.7 debug|   },\n
***  v1    0.7 debug|   ws = 0x2ab6d8050b08 {\n
***  v1    0.7 debug|     id = \"req\",\n
***  v1    0.7 debug|     {s, f, r, e} = {0x2ab6d8052908, +224, (nil), +57344},\n
***  v1    0.7 debug|   },\
***  v1    0.7 debug|   http_conn = 0x2ab6d8050a38 {\n***  v1    0.7 debug|     fd = 20,\n
***  v1    0.7 debug|     doclose = NULL,\n
***  v1    0.7 debug|     ws = 0x2ab6b058ae48,\n
***  v1    0.7 debug|     {rxbuf_b, rxbuf_e} = {0x2ab6b058a3f0, 0x2ab6b058a41a},\n
***  v1    0.7 debug|     {pipeline_b, pipeline_e} = {0x2ab6b058a3fe, 0x2ab6b058a41a},\n
***  v1    0.7 debug|     content_length = 0,\n
***  v1    0.7 debug|     body_status = none,\n
***  v1    0.7 debug|     first_byte_timeout = 0.000000,\n
***  v1    0.7 debug|     between_bytes_timeout = 0.000000,\n
***  v1    0.7 debug|   },\n
***  v1    0.7 debug|   http[req] = 0x2ab6d8050ba0 {\n
***  v1    0.7 debug|     ws[] = (nil),\n
***  v1    0.7 debug|     hdrs {\n
***  v1    0.7 debug|     },\n
***  v1    0.7 debug|   },\n
***  v1    0.7 debug|   flags = {\n
***  v1    0.7 debug|   },\n
***  v1    0.7 debug| },\n
***  v1    0.7 debug| \n
***  v1    0.7 debug| "\n
***  v1    0.7 debug| Debug: Child cleanup complete\n
---- c1    0.7 HTTP2 rx EOF (fd:11 read: Success)
#     top  TEST ./tests/t02000.vtc FAILED (60.009) signal=9 exit=0

[daghf]

Fixed in bdf117b

[hermunn]

Backport review: H2 only - nothing to backport.