When several requests were waiting for a response, then after getting
a CNAME response only the last request's context had the name updated.
Contexts of other requests had the wrong name. This name was used by
ngx_resolve_name_done() to find the node to remove the request context
from. When the name was wrong, the request could not be properly
cancelled, its context was freed but stayed linked to the node's waiting
list. This happened e.g. when the first request was aborted or timed
out before the resolving completed. When it completed, this triggered
a use-after-free memory access by calling ctx->handler of already freed
request context. The bug manifests itself by
"could not cancel <name> resolving" alerts in error_log.
When a request was responded with a CNAME, the request context kept
the pointer to the original node's rn->u.cname. If the original node
expired before the resolving timed out or completed with an error,
this would trigger a use-after-free memory access via ctx->name in
ctx->handler().
The fix is to keep ctx->name unmodified. The name from context
is no longer used by ngx_resolve_name_done(). Instead, we now keep
the pointer to resolver node to which this request is linked.
Keeping the original name intact also improves logging.
When several requests were waiting for a response, then after getting
a CNAME response only the last request was properly processed, while
others were left waiting.
If one or more requests were waiting for a response, then after
getting a CNAME response, the timeout event on the first request
remained active, pointing to the wrong node with an empty
rn->waiting list, and that could cause either null pointer
dereference or use-after-free memory access if this timeout
expired.
If several requests were waiting for a response, and the first
request terminated (e.g., due to client closing a connection),
other requests were left without a timeout and could potentially
wait indefinitely.
This is fixed by introducing per-request independent timeouts.
This change also reverts 954867a2f0a6 and 5004210e8c78.
OpenSSL doesn't check if the negotiated protocol has been announced.
As a result, the client might force using SPDY even if it wasn't
enabled in configuration.
The code failed to ensure that "s" is within the buffer passed for
parsing when checking for "ms", and this resulted in unexpected errors when
parsing non-null-terminated strings with trailing "m". The bug manifested
itself when the expires directive was used with variables.
Found by Roman Arutyunyan.
This context is needed for shared sessions cache to work in configurations
with multiple virtual servers sharing the same port. Unfortunately, OpenSSL
does not provide an API to access the session context, thus storing it
separately.
In collaboration with Vladimir Homutov.
The value of NGX_ERROR, returned from filter handlers, was treated as a generic
upstream error and changed to NGX_HTTP_INTERNAL_SERVER_ERROR before calling
ngx_http_finalize_request(). This resulted in "header already sent" alert
if header was already sent in filter handlers.
The problem appeared in 54e9b83d00f0 (1.7.5).
The following configuration with alias, nested location and try_files
resulted in wrong file being used. Request "/foo/test.gif" tried to
use "/tmp//foo/test.gif" instead of "/tmp/test.gif":
location /foo/ {
alias /tmp/;
location ~ gif {
try_files $uri =405;
}
}
Additionally, rev. c985d90a8d1f introduced a regression if
the "/tmp//foo/test.gif" file was found (ticket #768). Resulting URI
was set to "gif?/foo/test.gif", as the code used clcf->name of current
location ("location ~ gif") instead of parent one ("location /foo/").
Fix is to use r->uri instead of clcf->name in all cases in the
ngx_http_core_try_files_phase() function. It is expected to be
already matched and identical to the clcf->name of the right
location.
If alias was used in a location given by a regular expression,
nginx used to do wrong thing in try_files if a location name (i.e.,
regular expression) was an exact prefix of URI. The following
configuration triggered a segmentation fault on a request to "/mail":
location ~ /mail {
alias /path/to/directory;
try_files $uri =404;
}
Reported by Per Hansson.
This may happen if eventfd() returns ENOSYS, notably seen on CentOS 5.4.
Such a failure will now just disable the notification mechanism and let
the callers cope with it, instead of failing to start worker processes.
If thread pools are not configured, this can safely be ignored.
It's now enough to specify proxy_protocol option in one listen directive to
enable it in all servers listening on the same address/port. Previously,
the setting from the first directive was always used.
Similar to ngx_http_file_cache_set_slot(), the last component of file->name
with a fixed length of 10 bytes, as generated in ngx_create_temp_path(), is
used as a source for the names of intermediate subdirectories with each one
taking its own part. Ensure that the sum of specified levels with slashes
fits into the length (ticket #731).
Missing call to X509_STORE_CTX_free when X509_STORE_CTX_init fails.
Missing call to OCSP_CERTID_free when OCSP_request_add0_id fails.
Possible leaks in vary particular scenariis of memory shortage.
This helps to avoid suboptimal behavior when a client waits for a control
frame or more data to increase window size, but the frames have been delayed
in the socket buffer.
The delays can be caused by bad interaction between Nagle's algorithm on
nginx side and delayed ACK on the client side or by TCP_CORK/TCP_NOPUSH
if SPDY was working without SSL and sendfile() was used.
The pushing code is now very similar to ngx_http_set_keepalive().
If any preread body bytes were sent in the first chain, chunk size was
incorrectly added before the whole chain, including header, resulting in
an invalid request sent to upstream. Fixed to properly add chunk size
after the header.
The r->request_body_no_buffering flag was introduced. It instructs
client request body reading code to avoid reading the whole body, and
to call post_handler early instead. The caller should use the
ngx_http_read_unbuffered_request_body() function to read remaining
parts of the body.
Upstream module is now able to use this mode, if configured with
the proxy_request_buffering directive.
Maxim Dounin
Ruslan Ermilov
Roman Arutyunyan
Valentin Bartenev
Sergey Kandaurov
Vladimir Homutov
Filipe da Silva