| From e6ccbab5d42b110ac4f6ce1f72cb1e9ccbe4400a Mon Sep 17 00:00:00 2001 |
| From: Li xin <lixin.fnst@cn.fujitsu.com> |
| Date: Tue, 16 Jun 2015 19:02:38 +0900 |
| Subject: [PATCH] mod_cgi buffers data without bound so fix it |
| |
| Upstream-Status: Submitted [http://redmine.lighttpd.net/issues/1264] |
| |
| Signed-off-by: Li Xin <lixin.fnst@cn.fujitsu.com> |
| |
| Update context for 1.4.36. |
| |
| Signed-off-by: Kai Kang <kai.kang@windriver.com> |
| --- |
| doc/config/lighttpd.conf | 8 ++ |
| src/mod_cgi.c | 188 ++++++++++++++++++++++++++++++++++++++++++++--- |
| 2 files changed, 187 insertions(+), 9 deletions(-) |
| |
| diff --git a/doc/config/lighttpd.conf b/doc/config/lighttpd.conf |
| index 60b0ae1..9c101a7 100644 |
| --- a/doc/config/lighttpd.conf |
| +++ b/doc/config/lighttpd.conf |
| @@ -375,6 +375,14 @@ server.upload-dirs = ( "/var/tmp" ) |
| ## |
| ####################################################################### |
| |
| +####################################################################### |
| +## |
| +## |
| +## maximum bytes in send_raw before backing off [KByte] |
| +## cgi.high-waterlevel = 10240 |
| +## minimum bytes in send_raw to disable backoff [KByte] |
| +## cgi.low-waterlevel = 5120 |
| +####################################################################### |
| |
| ####################################################################### |
| ## |
| diff --git a/src/mod_cgi.c b/src/mod_cgi.c |
| index 01b1877..7c67eb5 100644 |
| --- a/src/mod_cgi.c |
| +++ b/src/mod_cgi.c |
| @@ -38,6 +38,10 @@ |
| |
| #include "version.h" |
| |
| +/* for output logs */ |
| +char msgbuf[2048]; |
| + |
| + |
| enum {EOL_UNSET, EOL_N, EOL_RN}; |
| |
| typedef struct { |
| @@ -53,9 +57,19 @@ typedef struct { |
| size_t size; |
| } buffer_pid_t; |
| |
| +struct handler_ctx; |
| + |
| +typedef struct { |
| + struct handler_ctx **hctx; |
| + size_t used; |
| + size_t size; |
| +} buffer_ctx_t; |
| + |
| typedef struct { |
| array *cgi; |
| unsigned short execute_x_only; |
| + unsigned int high_waterlevel; /* maximum bytes in send_raw before backing off */ |
| + unsigned int low_waterlevel; /* minimum bytes in send_raw to disable backoff */ |
| } plugin_config; |
| |
| typedef struct { |
| @@ -68,9 +82,11 @@ typedef struct { |
| plugin_config **config_storage; |
| |
| plugin_config conf; |
| + |
| + buffer_ctx_t cgi_ctx; |
| } plugin_data; |
| |
| -typedef struct { |
| +typedef struct handler_ctx { |
| pid_t pid; |
| int fd; |
| int fde_ndx; /* index into the fd-event buffer */ |
| @@ -78,11 +94,16 @@ typedef struct { |
| connection *remote_conn; /* dumb pointer */ |
| plugin_data *plugin_data; /* dumb pointer */ |
| |
| + int throttling; /* 1=waiting for send_raw buffer to drain */ |
| + off_t high_waterlevel; /* maximum bytes in send_raw before backing off */ |
| + off_t low_waterlevel; /* minimum bytes in send_raw to disable backoff */ |
| + off_t bytes_in_buffer; |
| + |
| buffer *response; |
| buffer *response_header; |
| } handler_ctx; |
| |
| -static handler_ctx * cgi_handler_ctx_init(void) { |
| +static handler_ctx * cgi_handler_ctx_init(plugin_data *p) { |
| handler_ctx *hctx = calloc(1, sizeof(*hctx)); |
| |
| force_assert(hctx); |
| @@ -90,13 +111,26 @@ static handler_ctx * cgi_handler_ctx_init(void) { |
| hctx->response = buffer_init(); |
| hctx->response_header = buffer_init(); |
| |
| + hctx->throttling = 0; |
| + hctx->high_waterlevel = (off_t)p->conf.high_waterlevel * 1024; |
| + hctx->low_waterlevel = (off_t)p->conf.low_waterlevel * 1024; |
| + if (hctx->low_waterlevel >= hctx->high_waterlevel) { |
| + hctx->low_waterlevel = hctx->high_waterlevel * 3 / 4; /* 75% */ |
| + } |
| + hctx->bytes_in_buffer = 0; |
| + |
| return hctx; |
| } |
| |
| -static void cgi_handler_ctx_free(handler_ctx *hctx) { |
| +static void cgi_handler_ctx_free(server *srv, handler_ctx *hctx) { |
| buffer_free(hctx->response); |
| buffer_free(hctx->response_header); |
| |
| + /* to avoid confusion */ |
| + if (hctx->throttling) { |
| + log_error_write(srv, __FILE__, __LINE__, "s", "unthrottled"); |
| + } |
| + |
| free(hctx); |
| } |
| |
| @@ -154,6 +188,8 @@ SETDEFAULTS_FUNC(mod_fastcgi_set_defaults) { |
| config_values_t cv[] = { |
| { "cgi.assign", NULL, T_CONFIG_ARRAY, T_CONFIG_SCOPE_CONNECTION }, /* 0 */ |
| { "cgi.execute-x-only", NULL, T_CONFIG_BOOLEAN, T_CONFIG_SCOPE_CONNECTION }, /* 1 */ |
| + { "cgi.high-waterlevel", NULL, T_CONFIG_INT, T_CONFIG_SCOPE_CONNECTION }, /* 2 */ |
| + { "cgi.low-waterlevel", NULL, T_CONFIG_INT, T_CONFIG_SCOPE_CONNECTION }, /* 3 */ |
| { NULL, NULL, T_CONFIG_UNSET, T_CONFIG_SCOPE_UNSET} |
| }; |
| |
| @@ -169,9 +205,13 @@ SETDEFAULTS_FUNC(mod_fastcgi_set_defaults) { |
| |
| s->cgi = array_init(); |
| s->execute_x_only = 0; |
| + s->high_waterlevel = 0; /* 0 == disabled */ |
| + s->low_waterlevel = 0; |
| |
| cv[0].destination = s->cgi; |
| cv[1].destination = &(s->execute_x_only); |
| + cv[2].destination = &(s->high_waterlevel); |
| + cv[3].destination = &(s->low_waterlevel); |
| |
| p->config_storage[i] = s; |
| |
| @@ -184,6 +224,51 @@ SETDEFAULTS_FUNC(mod_fastcgi_set_defaults) { |
| } |
| |
| |
| +static void cgi_recount_bytes_in_buffer(handler_ctx *hctx) |
| +{ |
| + chunkqueue *cq = hctx->remote_conn->write_queue; |
| + hctx->bytes_in_buffer = chunkqueue_length(cq) - chunkqueue_written(cq); |
| +} |
| + |
| + |
| +static void cgi_throttling_control(server *srv, handler_ctx *hctx) |
| +{ |
| + cgi_recount_bytes_in_buffer(hctx); |
| + |
| +#ifdef DEBUG |
| + sprintf(msgbuf, "throttling=%d, chars=%llu, high=%llu, low=%llu", |
| + hctx->throttling, hctx->bytes_in_buffer, |
| + hctx->high_waterlevel, hctx->low_waterlevel); |
| + log_error_write(srv, __FILE__, __LINE__, "ss", |
| + "(debug) throttling control,", msgbuf); |
| +#endif |
| + |
| + if (hctx->throttling) { |
| + sprintf(msgbuf, "throttling; chars in queue=%llu," |
| + " low-waterlevel=%llu, high-waterlevel=%llu", |
| + hctx->bytes_in_buffer, |
| + hctx->low_waterlevel, hctx->high_waterlevel); |
| + log_error_write(srv, __FILE__, __LINE__, "s", msgbuf); |
| + if (hctx->bytes_in_buffer <= hctx->low_waterlevel) { |
| + fdevent_event_set(srv->ev, &(hctx->fde_ndx), hctx->fd, FDEVENT_IN); |
| + hctx->throttling = 0; |
| + log_error_write(srv, __FILE__, __LINE__, "s", "unthrottled"); |
| + } |
| + } else { |
| + if (hctx->high_waterlevel != 0 && |
| + hctx->high_waterlevel <= hctx->bytes_in_buffer) { |
| + fdevent_event_del(srv->ev, &(hctx->fde_ndx), hctx->fd); |
| + hctx->throttling = 1; |
| + sprintf(msgbuf, "throttled; chars in queue=%llu," |
| + " low-waterlevel=%llu, high-waterlevel=%llu", |
| + hctx->bytes_in_buffer, |
| + hctx->low_waterlevel, hctx->high_waterlevel); |
| + log_error_write(srv, __FILE__, __LINE__, "s", msgbuf); |
| + } |
| + } |
| +} |
| + |
| + |
| static int cgi_pid_add(server *srv, plugin_data *p, pid_t pid) { |
| int m = -1; |
| size_t i; |
| @@ -230,6 +315,39 @@ static int cgi_pid_del(server *srv, plugin_data *p, pid_t pid) { |
| return 0; |
| } |
| |
| + |
| +static void cgi_ctx_add(plugin_data *p, handler_ctx *hctx) { |
| + buffer_ctx_t *r = &(p->cgi_ctx); |
| + |
| + if (r->size == 0) { |
| + r->size = 16; |
| + r->hctx = malloc(sizeof(*r->hctx) * r->size); |
| + } else if (r->used == r->size) { |
| + r->size += 16; |
| + r->hctx = realloc(r->hctx, sizeof(*r->hctx) * r->size); |
| + } |
| + |
| + r->hctx[r->used++] = hctx; |
| +} |
| + |
| +static void cgi_ctx_del(plugin_data *p, handler_ctx *hctx) { |
| + size_t i; |
| + buffer_ctx_t *r = &(p->cgi_ctx); |
| + |
| + for (i = 0; i < r->used; i++) { |
| + if (r->hctx[i] == hctx) break; |
| + } |
| + |
| + if (i != r->used) { |
| + /* found */ |
| + |
| + if (i != r->used - 1) { |
| + r->hctx[i] = r->hctx[r->used - 1]; |
| + } |
| + r->used--; |
| + } |
| +} |
| + |
| static int cgi_response_parse(server *srv, connection *con, plugin_data *p, buffer *in) { |
| char *ns; |
| const char *s; |
| @@ -380,6 +498,14 @@ static int cgi_demux_response(server *srv, handler_ctx *hctx) { |
| |
| buffer_commit(hctx->response, n); |
| |
| +#ifdef DEBUG |
| + sprintf(msgbuf, "n=%d, bytes_out=%llu, bytes_in=%llu", n, |
| + (unsigned long long)con->write_queue->bytes_out, |
| + (unsigned long long)con->write_queue->bytes_in); |
| + log_error_write(srv, __FILE__, __LINE__, "ss", |
| + "(debug) read,", msgbuf); |
| +#endif |
| + |
| /* split header from body */ |
| |
| if (con->file_started == 0) { |
| @@ -503,7 +629,20 @@ static int cgi_demux_response(server *srv, handler_ctx *hctx) { |
| } |
| } else { |
| http_chunk_append_buffer(srv, con, hctx->response); |
| +#ifdef DEBUG |
| + sprintf(msgbuf, "n=%d, bytes_out=%llu, bytes_in=%llu, limit=%llu", n, |
| + (unsigned long long)con->write_queue->bytes_out, |
| + (unsigned long long)con->write_queue->bytes_in, |
| + (unsigned long long)hctx->high_waterlevel); |
| + log_error_write(srv, __FILE__, __LINE__, |
| + "ss", "(debug) append,", msgbuf); |
| +#endif |
| joblist_append(srv, con); |
| + |
| + cgi_throttling_control(srv, hctx); |
| + if (hctx->throttling) { |
| + return FDEVENT_HANDLED_NOT_FINISHED; |
| + } |
| } |
| |
| #if 0 |
| @@ -553,8 +692,9 @@ static handler_t cgi_connection_close(server *srv, handler_ctx *hctx) { |
| con->plugin_ctx[p->id] = NULL; |
| |
| /* is this a good idea ? */ |
| - cgi_handler_ctx_free(hctx); |
| - |
| + cgi_ctx_del(p, hctx); |
| + cgi_handler_ctx_free(srv, hctx); |
| + |
| /* if waitpid hasn't been called by response.c yet, do it here */ |
| if (pid) { |
| /* check if the CGI-script is already gone */ |
| @@ -1105,7 +1245,8 @@ static int cgi_create_env(server *srv, connection *con, plugin_data *p, buffer * |
| con->mode = p->id; |
| buffer_reset(con->physical.path); |
| |
| - hctx = cgi_handler_ctx_init(); |
| + hctx = cgi_handler_ctx_init(p); |
| + cgi_ctx_add(p, hctx); |
| |
| hctx->remote_conn = con; |
| hctx->plugin_data = p; |
| @@ -1114,6 +1255,11 @@ static int cgi_create_env(server *srv, connection *con, plugin_data *p, buffer * |
| hctx->fde_ndx = -1; |
| |
| con->plugin_ctx[p->id] = hctx; |
| +#ifdef DEBUG |
| + sprintf(msgbuf, "hctx=%p, con=%p", (void*)hctx, (void*)con); |
| + log_error_write(srv, __FILE__, __LINE__, "ss", |
| + "(debug) hctx generated, ", msgbuf); |
| +#endif |
| |
| fdevent_register(srv->ev, hctx->fd, cgi_handle_fdevent, hctx); |
| fdevent_event_set(srv->ev, &(hctx->fde_ndx), hctx->fd, FDEVENT_IN); |
| @@ -1128,7 +1274,8 @@ static int cgi_create_env(server *srv, connection *con, plugin_data *p, buffer * |
| |
| close(hctx->fd); |
| |
| - cgi_handler_ctx_free(hctx); |
| + cgi_ctx_del(p, hctx); |
| + cgi_handler_ctx_free(srv, hctx); |
| |
| con->plugin_ctx[p->id] = NULL; |
| |
| @@ -1153,6 +1300,8 @@ static int mod_cgi_patch_connection(server *srv, connection *con, plugin_data *p |
| |
| PATCH(cgi); |
| PATCH(execute_x_only); |
| + PATCH(high_waterlevel); |
| + PATCH(low_waterlevel); |
| |
| /* skip the first, the global context */ |
| for (i = 1; i < srv->config_context->used; i++) { |
| @@ -1170,6 +1319,10 @@ static int mod_cgi_patch_connection(server *srv, connection *con, plugin_data *p |
| PATCH(cgi); |
| } else if (buffer_is_equal_string(du->key, CONST_STR_LEN("cgi.execute-x-only"))) { |
| PATCH(execute_x_only); |
| + } else if (buffer_is_equal_string(du->key, CONST_STR_LEN("cgi.high-waterlevel"))) { |
| + PATCH(high_waterlevel); |
| + } else if (buffer_is_equal_string(du->key, CONST_STR_LEN("cgi.low-waterlevel"))) { |
| + PATCH(low_waterlevel); |
| } |
| } |
| } |
| @@ -1222,6 +1375,21 @@ URIHANDLER_FUNC(cgi_is_handled) { |
| TRIGGER_FUNC(cgi_trigger) { |
| plugin_data *p = p_d; |
| size_t ndx; |
| + |
| + for (ndx = 0; ndx < p->cgi_ctx.used; ndx++) { |
| + handler_ctx *hctx = p->cgi_ctx.hctx[ndx]; |
| +#ifdef DEBUG |
| + connection *con = hctx->remote_conn; |
| + |
| + sprintf(msgbuf, "hctx=%p, con=%p, bytes_in_buffer=%llu", |
| + (void*)hctx, (void*)con, |
| + (unsigned long long)hctx->bytes_in_buffer); |
| + log_error_write(srv, __FILE__, __LINE__, "ss", |
| + "(debug) found using ctx,", msgbuf); |
| +#endif |
| + cgi_throttling_control(srv, hctx); |
| + } |
| + |
| /* the trigger handle only cares about lonely PID which we have to wait for */ |
| #ifndef __WIN32 |
| |
| @@ -1330,7 +1498,8 @@ SUBREQUEST_FUNC(mod_cgi_handle_subrequest) { |
| log_error_write(srv, __FILE__, __LINE__, "sds", "cgi close failed ", hctx->fd, strerror(errno)); |
| } |
| |
| - cgi_handler_ctx_free(hctx); |
| + cgi_ctx_del(p, hctx); |
| + cgi_handler_ctx_free(srv, hctx); |
| |
| con->plugin_ctx[p->id] = NULL; |
| |
| @@ -1362,7 +1531,8 @@ SUBREQUEST_FUNC(mod_cgi_handle_subrequest) { |
| log_error_write(srv, __FILE__, __LINE__, "sds", "cgi close failed ", hctx->fd, strerror(errno)); |
| } |
| |
| - cgi_handler_ctx_free(hctx); |
| + cgi_ctx_del(p, hctx); |
| + cgi_handler_ctx_free(srv, hctx); |
| |
| con->plugin_ctx[p->id] = NULL; |
| return HANDLER_FINISHED; |