This fixes segfault in configurations with multiple virtual servers sharing
the same port, where a non-default virtual server block misses certificate.
Following ad3f342f14ba046c (1.9.13), it is possible that a request where
header was already sent will be finalized with NGX_HTTP_BAD_GATEWAY,
triggering an attempt to return additional error response and the
"header already sent" alert as a result.
In particular, it is trivial to reproduce the problem with a HEAD request
and caching enabled. With caching enabled nginx will change HEAD to GET
and will set u->pipe->downstream_error to suppress sending the response
body to the client. When a backend-related error occurs (for example,
proxy_read_timeout expires), ngx_http_finalize_upstream_request() will
be called with NGX_HTTP_BAD_GATEWAY. After ad3f342f14ba046c this will
result in ngx_http_finalize_request(NGX_HTTP_BAD_GATEWAY).
Fix is to move u->pipe->downstream_error handling to a later point,
where all special response codes are changed to NGX_ERROR.
Reported by Jan Prachar,
http://mailman.nginx.org/pipermail/nginx-devel/2018-January/010737.html.
The capability is retained automatically in unprivileged worker processes after
changing UID if transparent proxying is enabled at least once in nginx
configuration.
The feature is only available in Linux.
If the flag space_in_uri is set, the URI in HTTP upstream request is escaped to
convert space to %20. However this flag is not checked while creating the
default cache key. This leads to different cache keys for requests
'/foo bar' and '/foo%20bar', while the upstream requests are identical.
Additionally, the change fixes background cache updates when the client URI
contains unescaped space. Default cache key in a subrequest is always based on
escaped URI, while the main request may not escape it. As a result, background
cache update subrequest may update a different cache entry.
Inheriting this flag will make the cloned subrequest behave consistently with
the parent. Specifically, the upstream HTTP request and cache key created by
the proxy module may depend directly on unparsed_uri if valid_unparsed_uri flag
is set. Previously, the flag was zero for cloned requests, which could make
background update proxy a request different than its parent and cache the result
with a different key. For example, if client URI contained the escaped slash
character %2F, it was used as is by the proxy module in the main request, but
was unescaped in the subrequests.
Similar problems exist in the slice module.
Previously, the unparsed uri was explicitly allowed to be used only by the main
request. However the valid_unparsed_uri flag is nonzero only in the main
request, which makes the main request check pointless.
If the data to write is bigger than what the socket can send, and the
reminder is smaller than NGX_SSL_BUFSIZE, then SSL_write() fails with
SSL_ERROR_WANT_WRITE. The reminder of payload however is successfully
copied to the low-level buffer and all the output chain buffers are
flushed. This means that retry logic doesn't work because
ngx_http_upstream_process_non_buffered_request() checks only if there's
anything in the output chain buffers and ignores the fact that something
may be buffered in low-level parts of the stack.
Signed-off-by: Patryk Lesiewicz <patryk@google.com>
If a connection with the read delayed flag set was stored in the keepalive
cache, and after picking it from the cache a read timer was set on that
connection, this timer was considered a delay timer rather than a socket read
event timer as expected. The latter timeout is usually much longer than the
former, which caused a significant delay in request processing.
The issue manifested itself with proxy_limit_rate and upstream keepalive
enabled and exists since 973ee2276300 (1.7.7) when proxy_limit_rate was
introduced.
The ngx_http_upstream_process_upgraded() did not handle c->close request,
and upgraded connections do not use the write filter. As a result,
worker_shutdown_timeout did not affect upgraded connections (ticket #1419).
Fix is to handle c->close in the ngx_http_request_handler() function, thus
covering most of the possible cases in http handling.
Additionally, mail proxying did not handle neither c->close nor c->error,
and thus worker_shutdown_timeout did not work for mail connections. Fix is
to add c->close handling to ngx_mail_proxy_handler().
Also, added explicit handling of c->close to stream proxy,
ngx_stream_proxy_process_connection(). This improves worker_shutdown_timeout
handling in stream, it will no longer wait for some data being transferred
in a connection before closing it, and will also provide appropriate
logging at the "info" level.
A zlib variant from Intel as available from https://github.com/jtkukunas/zlib
uses 64K hash instead of scaling it from the specified memory level, and
also uses 16-byte padding in one of the window-sized memory buffers, and can
force window bits to 13 if compression level is set to 1 and appropriate
compile options are used. As a result, nginx complained with "gzip filter
failed to use preallocated memory" alerts.
This change improves deflate_state allocation detection by testing that
items is 1 (deflate_state is the only allocation where items is 1).
Additionally, on first failure to use preallocated memory we now assume
that we are working with the Intel's modified zlib, and switch to using
appropriate preallocations. If this does not help, we complain with the
usual alerts.
Previous version of this patch was published at
http://mailman.nginx.org/pipermail/nginx/2014-July/044568.html.
The zlib variant in question is used by default in ClearLinux from Intel,
see http://mailman.nginx.org/pipermail/nginx-ru/2017-October/060421.html,
http://mailman.nginx.org/pipermail/nginx-ru/2017-November/060544.html.
Previously, nginx failed to move buffer position when parsing an incomplete
record header, and due to this wasn't be able to continue parsing once
remaining bytes of the record header were received.
This can affect response header parsing, potentially generating spurious errors
like "upstream sent unexpected FastCGI request id high byte: 1 while reading
response header from upstream". While this is very unlikely, since usually
record headers are written in a single buffer, this still can happen in real
life, for example, if a record header will be split across two TCP packets
and the second packet will be delayed.
This does not affect non-buffered response body proxying, due to "buf->pos =
buf->last;" at the start of the ngx_http_fastcgi_non_buffered_filter()
function. Also this does not affect buffered response body proxying, as
each input buffer is only passed to the filter once.
In particular, if ngx_http_postpone_filter_add() fails in ngx_chain_add_copy(),
the output chain of the postponed request was left in an invalid state.
Upgrading an upstream connection is usually followed by reading from the client
which a subrequest is not allowed to do. Moreover, accessing the header_in
request field while processing upgraded connection ends up with a null pointer
dereference since the header_in buffer is only created for the the main request.
If proxy_next_upstream includes http_503/http_504, and upstream
returns 503/504, $upstream_status converted this to 502 for any
values except the last one.
The NGX_DONE value returned from ngx_http_upstream_cache_send() indicates
that upstream was already finalized in ngx_http_upstream_process_headers().
It was treated as a generic error which resulted in duplicate finalization.
Handled NGX_HTTP_UPSTREAM_INVALID_HEADER from ngx_http_upstream_cache_send().
Previously, it could return within ngx_http_upstream_finalize_request(), and
since it's below NGX_HTTP_SPECIAL_RESPONSE, a client connection could stuck.
When parsing of headers in a cache file fails, already parsed headers
need to be cleared, and protocol state needs to be reinitialized. To do
so, u->request_sent is now set to ensure ngx_http_upstream_reinit() will
be called.
This change complements improvements in 46ddff109e72.
This slightly reduces cost of selecting a peer if all or almost all peers
failed, see ticket #1030. There should be no measureable difference with
other workloads.
While this may result in non-ideal distribution of requests if nginx
won't be able to select a server in a reasonable number of attempts,
this still looks better than severe performance degradation observed
if there is no limit and there are many points configured (ticket #1030).
This is also in line with what we do for other hash balancing methods.
Previously, unix sockets were treated as AF_INET ones, and this may
result in buffer overread on Linux, where unbound unix sockets have
2-byte addresses.
Note that it is not correct to use just sun_path as a binary representation
for unix sockets. This will result in an empty string for unbound unix
sockets, and thus behaviour of limit_req and limit_conn will change when
switching from $remote_addr to $binary_remote_addr. As such, normal text
representation is used.
Reported by Stephan Dollberg.
The sync flag of HTTP/2 request body buffer is used when the size of request
body is unknown or bigger than configured "client_body_buffer_size". In this
case the buffer points to body data inside the global receive buffer that is
used for reading all HTTP/2 connections in the worker process. Thus, when the
sync flag is set, the buffer must be flushed to a temporary file, otherwise
the request body data can be overwritten.
Previously, the sync buffer wasn't flushed to a temporary file if the whole
body was received in one DATA frame with the END_STREAM flag and wasn't
copied into the HTTP/2 body preread buffer. As a result, the request body
might be corrupted (ticket #1384).
Now, setting r->request_body_in_file_only enforces writing the sync buffer
to a temporary file in all cases.
When caching intercepted errors, previous behaviour was to use
proxy_cache_valid times specified, regardless of various cache control
headers present in the response. Fix is to check u->cacheable and
use u->cache->valid_sec as set by various cache control response headers,
similar to how we do this in the normal caching code path.
If cache file is truncated, it is possible that u->process_header()
will return NGX_AGAIN. Added appropriate handling of this case by
changing the error to NGX_HTTP_UPSTREAM_INVALID_HEADER.
Also, added appropriate logging of this and NGX_HTTP_UPSTREAM_INVALID_HEADER
cases at the "crit" level. Note that this will result in duplicate logging
in case of NGX_HTTP_UPSTREAM_INVALID_HEADER. While this is something better
to avoid, it is considered to be an overkill to implement cache-specific
error logging in u->process_header().
Additionally, u->buffer.start is now reset to be able to receive a new
response, and u->cache_status set to MISS to provide the value in the
$upstream_cache_status variable, much like it happens on other cache file
errors detected by ngx_http_file_cache_read(), instead of HIT, which is
believed to be misleading.
It is to be used as a bitmask with various bits set/reset when appropriate.
63b8b157b776 made a similar change to ngx_http_upstream_rr_peer_t.down and
ngx_stream_upstream_rr_peer_t.down.
Previously, "get indexed header" message was logged when in fact only
header name was obtained using an index, and "get indexed header name"
was logged when full header representation (name and value) was obtained
using an index. Fixed version logs "get indexed name" and "get indexed
header" respectively.
This change lets NGINX talk to clients with SETTINGS_HEADER_TABLE_SIZE
smaller than the default 4KB. Previously, NGINX would ACK the SETTINGS
frame with a small dynamic table size, but it would never send dynamic
table size update, leading to a connection-level COMPRESSION_ERROR.
Also, it allows clients to release 4KB of memory per connection, since
NGINX doesn't use HPACK's dynamic table when encoding headers, however
clients had to maintain it, since NGINX never signaled that it doesn't
use it.
Signed-off-by: Piotr Sikora <piotrsikora@google.com>
When secure link checksum has length of 23 or 24 bytes, decoded base64 value
could occupy 17 or 18 bytes which is more than 16 bytes previously allocated
for it on stack. The buffer overflow does not have any security implications
since only one local variable was corrupted and this variable was not used in
this case.
The fix is to increase buffer size up to 18 bytes. Useless buffer size
initialization is removed as well.
This fixes at least the following cases, where no last_modified_time
(assuming caching is not enabled) resulted in incorrect behaviour:
- slice filter and If-Range requests (ticket #1357);
- If-Range requests with proxy_force_ranges;
- expires modified.
This variable contains URL-encoded client SSL certificate. In contrast
to $ssl_client_cert, it doesn't depend on deprecated header continuation.
The NGX_ESCAPE_URI_COMPONENT variant of encoding is used, so the resulting
variable can be safely used not only in headers, but also as a request
argument.
The $ssl_client_cert variable should be considered deprecated now.
The $ssl_client_raw_cert variable will be eventually renambed back
to $ssl_client_cert.
Total length of a response with multiple ranges can be larger than a size_t
variable can hold, so type changed to off_t. Previously, an incorrect
Content-Length was returned when requesting more than 4G of ranges from
a large enough file on a 32-bit system.
An additional size_t variable introduced to calculate size of the boundary
header buffer, as off_t is not needed here and will require type casts on
win32.
Reported by Shuxin Yang,
http://mailman.nginx.org/pipermail/nginx/2017-July/054384.html.
Pass NGX_FILE_OPEN to ngx_open_file() to fix "The parameter is incorrect"
error on win32 when using the ssl_session_ticket_key directive or loading
a binary geo base. On UNIX, this change is a no-op.
The variable was considered non-existent in the absence of any
valid_referers directives.
Given the following config snippet,
location / {
return 200 $invalid_referer;
}
location /referer {
valid_referers server_names;
}
"location /" should work identically and independently on other
"location /referer".
The fix is to always add the $invalid_referer variable as long
as the module is compiled in, as is done by other modules.
The shared objects should generally be allocated from shared memory.
While peers->name and the data it points to allocated from cf->pool
happened to work on UNIX, it broke on Windows. On UNIX this worked
only because the shared memory zone for upstreams is re-created for
every new configuration.
But on Windows, a worker process does not inherit the address space
of the master process, so the peers->name pointed to data allocated
from cf->pool by the master process, and was invalid.