HTTP/2: fixed segfault on DATA frames after 400 errors. If 400 errors were redirected to an upstream server using the error_page directive, DATA frames from the client might cause segmentation fault due to null pointer dereference. The bug had appeared in 6989:2c4dbcd6f2e4 (1.13.0). Fix is to skip such frames in ngx_http_v2_state_read_data() (similarly to 7561:9f1f9d6e056a). With the fix, behaviour of 400 errors in HTTP/2 is now similar to one in HTTP/1.x, that is, nginx doesn't try to read the request body. Note that proxying 400 errors, as well as other early stage errors, to upstream servers might not be a good idea anyway. These errors imply that reading and processing of the request (and the request headers) wasn't complete, and proxying of such incomplete request might lead to various errors. Reported by Chenglong Zhang.

# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


NGX_MAKEFILE=$NGX_OBJS/Makefile
NGX_MODULES_C=$NGX_OBJS/ngx_modules.c

NGX_AUTO_HEADERS_H=$NGX_OBJS/ngx_auto_headers.h
NGX_AUTO_CONFIG_H=$NGX_OBJS/ngx_auto_config.h

NGX_AUTOTEST=$NGX_OBJS/autotest
NGX_AUTOCONF_ERR=$NGX_OBJS/autoconf.err

# STUBs
NGX_ERR=$NGX_OBJS/autoconf.err
MAKEFILE=$NGX_OBJS/Makefile


NGX_PCH=
NGX_USE_PCH=


# check the echo's "-n" option and "\c" capability

if echo "test\c" | grep c >/dev/null; then

    if echo -n test | grep n >/dev/null; then
        ngx_n=
        ngx_c=

    else
        ngx_n=-n
        ngx_c=
    fi

else
    ngx_n=
    ngx_c='\c'
fi


# create Makefile

cat << END > Makefile

default:	build

clean:
	rm -rf Makefile $NGX_OBJS
END