Custom Query (2311 matches)

Having this as SystemD override configuration :

# cat /etc/systemd/system/nginx.service.d/override.conf 
[Service]

PIDFile=/run/nginx/nginx.pid

RuntimeDirectory=nginx
RuntimeDirectoryMode=0775

LimitNOFILE=1048576

and this as the begining of my nginx.conf :

# cat /etc/nginx/nginx.conf 
user					nginx www-data;
...

I get this error in my main Nginx error log :

2023/12/03 17:55:05 [warn] 624580#624580: the "user" directive makes sense only if the master process runs with super-user privileges, ignored in /etc/nginx/nginx.conf:1
2023/12/03 17:55:05 [emerg] 624580#624580: open() "/run/nginx/nginx.pid" failed (13: Permission denied)

While I do not user the User nor Group directive inside the Nginx's SystemD service configuration.. so nginx master process runs as root before downgrading, so the error has no sense.

For information :

# ls -la /run/nginx
total 2
drwxrwxr-x  2 root root  100 Dec  3 17:55 .
drwxr-xr-x 45 root root 1380 Dec  3 17:55 ..
-rw-r--r--  1 root root    7 Dec  3 17:55 nginx.pid

Thank you in advance for your help.

memcpying to or from NULL is undefined behavior, even when the copy is of size 0.

Nginx executes a memcpy from NULL during startup with the default configuration. This can be reproduced very easily as follows:

0. Build and install Nginx with GCC 12.2.0 on x86_64 Linux using the default configuration.
1. Run Nginx under gdb, setting the appropriate breakpoints:

   gdb -ex 'b ngx_pstrdup' -ex 'r' -ex 'c' -ex 'c' -ex 'b memcpy' -ex 'c' -ex 'print $rsi' /usr/local/nginx/sbin/nginx
   

2. Observe that the second argument to memcpy is NULL:

   GNU gdb (Debian 13.1-3) 13.1
   Copyright (C) 2023 Free Software Foundation, Inc.
   License GPLv3+: GNU GPL version 3 or later <LINK OMITTED>
   This is free software: you are free to change and redistribute it.
   There is NO WARRANTY, to the extent permitted by law.
   Type "show copying" and "show warranty" for details.
   This GDB was configured as "x86_64-linux-gnu".
   Type "show configuration" for configuration details.
   For bug reporting instructions, please see:
   <LINK OMITTED>.
   Find the GDB manual and other documentation resources online at:
       <LINK OMITTED>.
   
   For help, type "help".
   Type "apropos word" to search for commands related to "word"...
   Reading symbols from /usr/local/nginx/sbin/nginx...
   Breakpoint 1 at 0x1ea6c: file src/core/ngx_string.c, line 76.
   Starting program: /usr/local/nginx/sbin/nginx
   warning: Error disabling address space randomization: Operation not permitted
   [Thread debugging using libthread_db enabled]
   Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
   
   Breakpoint 1, ngx_pstrdup (pool=pool@entry=0x55c897c5e4d0, src=src@entry=0x7ffcbb97b358)
       at src/core/ngx_string.c:76
   76	{
   Continuing.
   
   Breakpoint 1, ngx_pstrdup (pool=pool@entry=0x55c897c5e4d0, src=src@entry=0x7ffcbb97b368)
       at src/core/ngx_string.c:76
   76	{
   Continuing.
   
   Breakpoint 1, ngx_pstrdup (pool=pool@entry=0x55c897c5e4d0, src=src@entry=0x7ffcbb97b348)
       at src/core/ngx_string.c:76
   76	{
   Breakpoint 2 at 0x7f3413660cc0: memcpy. (4 locations)
   Continuing.
   
   Breakpoint 2.3, __memcpy_avx_unaligned_erms ()
       at ../sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S:264
   264	../sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S: No such file or directory.
   $1 = 0
   

This was found with UBSan. I have tested it both on the development branch, as well as 1.22.1, and the issue is present in both.

Hello I've read same bugs here but they were closed so I open a new one since I believe its not logic condition.

nginx relevant config:

proxy_cache_background_update on;
proxy_cache_key                "$MOBILE$scheme$host$request_uri";
proxy_cache_lock               on;
proxy_cache_methods            GET HEAD;
proxy_cache_use_stale          timeout invalid_header updating http_429 http_500 http_502 http_503 http_504 http_403; # 

proxy_cache_valid              200 15s;
proxy_cache_valid              404 15s;

--- I create simple file 404.txt and doing curl two times:

curl https://x.x.x/404.txt -k -I
HTTP/2 200 
server: nginx
date: Sun, 26 Nov 2023 07:44:29 GMT
content-type: text/plain; charset=UTF-8
content-length: 6
x-powered-by: WP Rocket/3.10.3
cache-control: public
x-xss-protection: 1; mode=block
x-content-type-options: nosniff
x-nginx-upstream-cache-status: MISS
accept-ranges: bytes

again:

HTTP/2 200 
server: nginx
date: Sun, 26 Nov 2023 07:44:31 GMT
content-type: text/plain; charset=UTF-8
content-length: 6
x-powered-by: WP Rocket/3.10.3
cache-control: public
x-xss-protection: 1; mode=block
x-content-type-options: nosniff
x-nginx-upstream-cache-status: HIT
accept-ranges: bytes

As you see now the file is cached in nginx. Now I go and remove this file from server and doing curl again 4 times:

curl https://x.x.x/404.txt -k -I
HTTP/2 200 
server: nginx
date: Sun, 26 Nov 2023 07:45:27 GMT
content-type: text/plain; charset=UTF-8
content-length: 6
x-powered-by: WP Rocket/3.10.3
cache-control: public
x-xss-protection: 1; mode=block
x-content-type-options: nosniff
x-nginx-upstream-cache-status: STALE
accept-ranges: bytes

HTTP/2 200 
server: nginx
date: Sun, 26 Nov 2023 07:45:29 GMT
content-type: text/plain; charset=UTF-8
content-length: 6
x-powered-by: WP Rocket/3.10.3
cache-control: public
x-xss-protection: 1; mode=block
x-content-type-options: nosniff
x-nginx-upstream-cache-status: STALE
accept-ranges: bytes

HTTP/2 200 
server: nginx
date: Sun, 26 Nov 2023 07:46:34 GMT
content-type: text/plain; charset=UTF-8
content-length: 6
x-powered-by: WP Rocket/3.10.3
cache-control: public
x-xss-protection: 1; mode=block
x-content-type-options: nosniff
x-nginx-upstream-cache-status: UPDATING
accept-ranges: bytes

HTTP/2 200 
server: nginx
date: Sun, 26 Nov 2023 07:46:48 GMT
content-type: text/plain; charset=UTF-8
content-length: 6
x-powered-by: WP Rocket/3.10.3
cache-control: public
x-xss-protection: 1; mode=block
x-content-type-options: nosniff
x-nginx-upstream-cache-status: STALE
accept-ranges: bytes

nginx log:

10.15.1.15 - STALE [26/Nov/2023:10:25:24 +0200]  "HEAD /404.txt HTTP/2.0" 200 0 "-" "curl/7.74.0"

Now it stales forever, it never refresh. I tried to add/remove this config:

proxy_cache_valid              404 15s;

but it doesn't change the behavior. When I manually remove all cache files from nginx or if I add cache buster i.e:

curl https://x.x.x/404.txt?1=1

it begins to return 404.

10.15.1.15 - MISS [26/Nov/2023:10:27:05 +0200]  "HEAD /404.txt?1=1 HTTP/2.0" 404 0 "-" "curl/7.74.0"

Please advise how to proceed. Dmitry Sherman