Sorry for disturbing. But I have to fix a buffer overflow bug.
Here is the latest patch.

Sorry. But please make your comments. Thank you.


diff --git a/src/http/ngx_http_request.c b/src/http/ngx_http_request.c
index 89cfe77a..c51d8ace 100644
--- a/src/http/ngx_http_request.c
+++ b/src/http/ngx_http_request.c
@@ -17,6 +17,10 @@ static ssize_t ngx_http_read_request_header(ngx_http_request_t *r);
static ngx_int_t ngx_http_alloc_large_header_buffer(ngx_http_request_t *r,
ngx_uint_t request_line);

+#if (NGX_HTTP_V2)
+static void ngx_http_wait_v2_preface_handler(ngx_event_t *rev);
+#endif
+
static ngx_int_t ngx_http_process_header_line(ngx_http_request_t *r,
ngx_table_elt_t *h, ngx_uint_t offset);
static ngx_int_t ngx_http_process_unique_header_line(ngx_http_request_t *r,
@@ -321,7 +325,7 @@ ngx_http_init_connection(ngx_connection_t *c)

#if (NGX_HTTP_V2)
if (hc->addr_conf->http2) {
- rev->handler = ngx_http_v2_init;
+ rev->handler = ngx_http_wait_v2_preface_handler;
}
#endif

@@ -377,6 +381,110 @@ ngx_http_init_connection(ngx_connection_t *c)
}


+#if (NGX_HTTP_V2)
+static void
+ngx_http_wait_v2_preface_handler(ngx_event_t *rev)
+{
+ size_t size;
+ ssize_t n;
+ ngx_buf_t *b;
+ ngx_connection_t *c;
+ static const u_char preface[] = "PRI";
+
+ c = rev->data;
+ size = sizeof(preface) - 1;
+
+ ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0,
+ "http wait h2 preface handler");
+
+ if (rev->timedout) {
+ ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
+ ngx_http_close_connection(c);
+ return;
+ }
+
+ if (c->close) {
+ ngx_http_close_connection(c);
+ return;
+ }
+
+ b = c->buffer;
+
+ if (b == NULL) {
+ b = ngx_create_temp_buf(c->pool, size);
+ if (b == NULL) {
+ ngx_http_close_connection(c);
+ return;
+ }
+
+ c->buffer = b;
+
+ } else if (b->start == NULL) {
+
+ b->start = ngx_palloc(c->pool, size);
+ if (b->start == NULL) {
+ ngx_http_close_connection(c);
+ return;
+ }
+
+ b->pos = b->start;
+ b->last = b->start;
+ b->end = b->last + size;
+ }
+
+ n = c->recv(c, b->last, b->end - b->last);
+
+ if (n == NGX_AGAIN) {
+
+ if (!rev->timer_set) {
+ ngx_add_timer(rev, c->listening->post_accept_timeout);
+ ngx_reusable_connection(c, 1);
+ }
+
+ if (ngx_handle_read_event(rev, 0) != NGX_OK) {
+ ngx_http_close_connection(c);
+ return;
+ }
+
+ /*
+ * We are trying to not hold c->buffer's memory for an idle connection.
+ */
+
+ if (ngx_pfree(c->pool, b->start) == NGX_OK) {
+ b->start = NULL;
+ }
+
+ return;
+ }
+
+ if (n == NGX_ERROR) {
+ ngx_http_close_connection(c);
+ return;
+ }
+
+ if (n == 0) {
+ ngx_log_error(NGX_LOG_INFO, c->log, 0,
+ "client closed connection");
+ ngx_http_close_connection(c);
+ return;
+ }
+
+ b->last += n;
+
+ if (b->last == b->end) {
+ /* b will be freed in ngx_http_v2_init/ngx_http_wait_request_handler */
+
+ if (ngx_strncmp(b->start, preface, size) == 0) {
+ ngx_http_v2_init(rev);
+ } else {
+ rev->handler = ngx_http_wait_request_handler;
+ ngx_http_wait_request_handler(rev);
+ }
+ }
+}
+#endif
+
+
static void
ngx_http_wait_request_handler(ngx_event_t *rev)
{
@@ -430,6 +538,22 @@ ngx_http_wait_request_handler(ngx_event_t *rev)
b->pos = b->start;
b->last = b->start;
b->end = b->last + size;
+ } else {
+
+ p = ngx_palloc(c->pool, size);
+ if (p == NULL) {
+ ngx_http_close_connection(c);
+ return;
+ }
+
+ n = b->last - b->start;
+ ngx_memcpy(p, b->start, n);
+ ngx_pfree(c->pool, b->start);
+
+ b->start = p;
+ b->pos = b->start;
+ b->last = b->start + n;
+ b->end = b->last + size;
}

n = c->recv(c, b->last, size);
diff --git a/src/http/v2/ngx_http_v2.c b/src/http/v2/ngx_http_v2.c
index d9df0f90..e36bf382 100644
--- a/src/http/v2/ngx_http_v2.c
+++ b/src/http/v2/ngx_http_v2.c
@@ -231,6 +231,8 @@ static ngx_http_v2_parse_header_t ngx_http_v2_parse_headers[] = {
void
ngx_http_v2_init(ngx_event_t *rev)
{
+ size_t size;
+ ngx_buf_t *b;
ngx_connection_t *c;
ngx_pool_cleanup_t *cln;
ngx_http_connection_t *hc;
@@ -262,6 +264,23 @@ ngx_http_v2_init(ngx_event_t *rev)
return;
}

+ b = c->buffer;
+
+ if (b != NULL) {
+ size = b->last - b->start;
+
+ if (size > h2mcf->recv_buffer_size) {
+ size = h2mcf->recv_buffer_size;
+ }
+
+ ngx_memcpy(h2mcf->recv_buffer, b->start, size);
+ h2c->state.buffer_used = size;
+
+ ngx_pfree(c->pool, b->start);
+ ngx_pfree(c->pool, b);
+ c->buffer = NULL;
+ }
+
h2c->connection = c;
h2c->http_connection = hc;

@@ -381,13 +400,15 @@ ngx_http_v2_read_handler(ngx_event_t *rev)
h2mcf = ngx_http_get_module_main_conf(h2c->http_connection->conf_ctx,
ngx_http_v2_module);

- available = h2mcf->recv_buffer_size - 2 * NGX_HTTP_V2_STATE_BUFFER_SIZE;
+ available = h2mcf->recv_buffer_size - h2c->state.buffer_used - 2 * NGX_HTTP_V2_STATE_BUFFER_SIZE;

do {
p = h2mcf->recv_buffer;

- ngx_memcpy(p, h2c->state.buffer, NGX_HTTP_V2_STATE_BUFFER_SIZE);
end = p + h2c->state.buffer_used;
+ if (h2c->state.buffer_used == 0) {
+ ngx_memcpy(p, h2c->state.buffer, NGX_HTTP_V2_STATE_BUFFER_SIZE);
+ }

n = c->recv(c, end, available);




> On Mar 6, 2018, at 03:14, Maxim Dounin <mdounin@mdounin.ru> wrote:
>
> Hello!
>
> On Mon, Mar 05, 2018 at 11:52:57PM +0800, Haitao Lv wrote:
>
> [...]
>
>>> Overall, the patch looks like a hack and introduces too much
>>> complexity for this feature. While I understand the reasoning,
>>> the proposed implementation cannot be accepted.
>>
>> Could you clarify that whether is this feature not accepted or this patch?
>>
>> If this feature is not needed, I will terminate this thread.
>>
>> If this patch only looks like a hack, would you like offer any advice to write
>> code with good smell?
>
> We've previously discussed this with Valentin, and our position is
> as follows:
>
> - The feature itself (autodetection between HTTP/2 and HTTP/1.x
> protocols) might be usable, and we can consider adding it if
> there will be a good and simple enough patch. (Moreover, we
> think that this probably should be the default if "listen ...
> http2" is configured - that is, no "http1" option.)
>
> - The patch suggested certainly doesn't meet the above criteria,
> and it does not look like it can be fixed.
>
> We don't know if a good and simple enough implementation is at all
> possible though. One of the possible approaches was already
> proposed by Valentin (detect HTTP/2 or HTTP/1.x before starting
> processing, may be similar to how we handle http-to-https
> requests), but it's now immediately clear if it will work or not.
> Sorry, but please don't expect any of us to provide further
> guidance.
>
> --
> Maxim Dounin
> http://mdounin.ru/
> _______________________________________________
> nginx-devel mailing list
> nginx-devel@nginx.org
> http://mailman.nginx.org/mailman/listinfo/nginx-devel



_______________________________________________
nginx-devel mailing list
nginx-devel@nginx.org
http://mailman.nginx.org/mailman/listinfo/nginx-devel