Configuration like
location / {
set $true 1;
if ($true) {
proxy_pass http://backend;
}
if ($true) {
# nothing
}
}
resulted in segmentation fault due to NULL pointer dereference as the
upstream configuration wasn't initialized in an implicit location created
by the last if(), but the r->content_handler was set due to first if().
Instead of committing a suicide by dereferencing a NULL pointer, return
500 (Internal Server Error) in such cases, i.e. if uscf is NULL. Better
fix would be to avoid such cases by fixing the "if" directive handling,
but it's out of scope of this patch.
Prodded by Piotr Sikora.
On Mac OS X system toolchain by default prefers include files
from /usr/local/include, but libraries from /usr/lib. This might result in
various problems, in particular the one outlined below.
If the PCRE library is installed into /usr/local/, this results in pcre.h
being used from /usr/local/include (with PCRE_CONFIG_JIT defined), but
libpcre from /usr/lib (as shipped with the OS, without pcre_free_study()
symbol). As a result build fails as we use pcre_free_study() function
if we try to compile with PCRE JIT support.
Obvious workaround is to the root cause is to ask compiler to prefer
library from /usr/local/lib via ./configure --with-ld-opt="-L/usr/local/lib".
On the other hand, in any case it would be good to check if the function
we are going to use is available, hence the change.
See thread here for details:
http://mailman.nginx.org/pipermail/nginx-devel/2012-December/003074.html
Prodded by Piotr Sikora.
This will result in alphabetical sorting of included files if
the "include" directive with wildcards is used.
Note that the behaviour is now different from that on Windows, where
alphabetical sorting is not guaranteed for FindFirsFile()/FindNextFile()
(used to be alphabetical on NTFS, but not on FAT).
Approved by Igor Sysoev, prodded by many.
Catched by dav_chunked.t on Solaris. In released versions this might
potentially result in corruption of complex protocol responses if they
were written to disk and there were more distinct buffers than IOV_MAX
in a single write.
If write events are not blocked, an extra write event might happen for
various reasons (e.g. as a result of a http pipelining), resulting in
incorrect body being passed to a post handler.
The problem manifested itself with the dav module only, as this is
the only module which reads the body from a content phase handler (in
contrast to exclusive content handlers like proxy). Additionally, dav
module used to dump core in such situations due to ticket #238.
See reports here:
http://mailman.nginx.org/pipermail/nginx-devel/2012-November/002981.htmlhttp://serverfault.com/questions/449195/nginx-webdav-server-with-auth-request
While discarding chunked request body in some cases after detecting
request body corruption no error was returned, while it was possible
to correctly return 400 Bad Request. If error is detected too late,
make sure to properly close connection.
Additionally, in ngx_http_special_response_handler() don't return body
of 500 Internal Server Error to a client if ngx_http_discard_request_body()
fails, but disable keepalive and continue.
Even if there is no preread data, make sure to always call
ngx_http_discard_request_body_filter() in case of chunked request
body to initialize r->headers_in.content_length_n for later use.
nginx doesn't allow the same shared memory zone to be used for different
purposes, but failed to check this on reconfiguration. If a shared memory
zone was used for another purpose in the new configuration, nginx attempted
to reuse it and crashed.
An attempt to call ngx_handle_read_event() before actually reading
data from a socket might result in read event being disabled, which is
wrong. Catched by body.t test on Solaris.
The r->main->count reference counter was always incremented in
ngx_http_read_client_request_body(), while it is only needs to be
incremented on positive returns.
The $request_body variable was assuming there can't be more than two
buffers. While this is currently true due to request body reading
implementation details, this is not a good thing to depend on and may
change in the future.
It is not about "Method" but a generic message, and is expected to be used
e.g. if specified Transfer-Encoding is not supported. Fixed message to
match RFC 2616.
Additionally, disable keepalive on such errors as we won't be able to read
request body correctly if we don't understand Transfer-Encoding used.
If request body reading happens with different options it's possible
that there will be no r->request_body->temp_file available (or even
no r->request_body available if body was discarded). Return internal
server error in this case instead of committing suicide by dereferencing
a null pointer.
Pending EOF might be reported on both read and write events, whichever
comes first, so check both of them.
Patch by Yichun Zhang (agentzh), slightly modified.
If an upstream block was defined with the only server marked as
"down", e.g.
upstream u {
server 127.0.0.1:8080 down;
}
an attempt was made to contact the server despite the "down" flag.
It is believed that immediate 502 response is better in such a
case, and it's also consistent with what is currently done in case
of multiple servers all marked as "down".
Input filter might free a buffer if there is no data in it, and in case
of first buffer (used for cache header and request header, aka p->buf_to_file)
this resulted in cache corruption. Buffer memory was reused to read upstream
response before headers were written to disk.
Fix is to avoid moving pointers in ngx_event_pipe_add_free_buf() to a buffer
start if we were asked to free a buffer used by p->buf_to_file.
This fixes occasional cache file corruption, usually resulted
in "cache file ... has md5 collision" alerts.
Reported by Anatoli Marinov.
idle connections.
This behaviour is consistent with the ngx_http_set_keepalive() function and it
should decrease memory usage in some cases (especially if epoll/rtsig is used).
