[ruby-core:62603] [ruby-trunk - Feature #9842] system configuration variables (sysconf(), confstr(), pathconf() and fpathconf())

Issue #9842 has been updated by Motohiro KOSAKI.


 On Thu, May 15, 2014 at 7:45 AM,  <[e-mail]> wrote:
 > Issue #9842 has been reported by Akira Tanaka.
 >
 > ----------------------------------------
 > Feature #9842: system configuration variables (sysconf(), confstr(), pathconf() and fpathconf())
 > https://bugs.ruby-lang.org/issues/9842
 >
 > * Author: Akira Tanaka
 > * Status: Open
 > * Priority: Normal
 > * Assignee:
 > * Category:
 > * Target version:
 > ----------------------------------------
 > How about providing methods to obtain system configuration variables?
 >
 > POSIX defines sysconf(), confstr(), pathconf() and fpathconf().
 > I implemented following methods in ext/etc.
 >
 > * Etc.sysconf(name)
 > * Etc.confstr(name)
 > * IO.pathconf(name)
 > * IO#pathconf(name)
 >
 > POSIX defines some names.
 > Various operating sysmtems define additional names.
 >
 > They can be used as follows:
 >
 > ```
 > Etc.sysconf(Etc::SC_ARG_MAX) #=> 2097152
 > Etc.sysconf(Etc::SC_NPROCESSORS_ONLN) #=> 4
 > Etc.confstr(Etc::CS_PATH) #=> "/bin:/usr/bin"
 > Etc.confstr(Etc::CS_GNU_LIBC_VERSION) #=> "glibc 2.18"
 > IO.pathconf("/", Etc::PC_NAME_MAX) #=> 255
 
 Please drop this. This is broken by design. If an attacker create a
 symlink which point
 to FAT file system on the same place, IO.patchconf(PC_NAME_MAX) may return very
 small size and might lead to security issue.
 
 http://womble.decadent.org.uk/readdir_r-advisory.html
 
 
 Or, at least, we need loooong document why you need much care about IO.pathconf.
 
 
 > open("/") {|f| p f.pathconf(Etc::PC_TIMESTAMP_RESOLUTION) } #=> 1
 > ```
 >
 > I implemented them in ext/etc because I interpreted "etc" as
 > system configuration.
 >
 > Any idea?
 >
 >
 > ---Files--------------------------------
 > sysconf-confstr-pathconf.patch (13 KB)
 >
 >
 > --
 > https://bugs.ruby-lang.org/

----------------------------------------
Feature #9842: system configuration variables (sysconf(), confstr(), pathconf() and fpathconf())
https://bugs.ruby-lang.org/issues/9842#change-46743

* Author: Akira Tanaka
* Status: Open
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
----------------------------------------
How about providing methods to obtain system configuration variables?

POSIX defines sysconf(), confstr(), pathconf() and fpathconf().
I implemented following methods in ext/etc.

* Etc.sysconf(name)
* Etc.confstr(name)
* IO.pathconf(name)
* IO#pathconf(name)

POSIX defines some names.
Various operating sysmtems define additional names.

They can be used as follows:

```
Etc.sysconf(Etc::SC_ARG_MAX) #=> 2097152
Etc.sysconf(Etc::SC_NPROCESSORS_ONLN) #=> 4
Etc.confstr(Etc::CS_PATH) #=> "/bin:/usr/bin"
Etc.confstr(Etc::CS_GNU_LIBC_VERSION) #=> "glibc 2.18"
IO.pathconf("/", Etc::PC_NAME_MAX) #=> 255
open("/") {|f| p f.pathconf(Etc::PC_TIMESTAMP_RESOLUTION) } #=> 1
```

I implemented them in ext/etc because I interpreted "etc" as
system configuration.

Any idea?


---Files--------------------------------
sysconf-confstr-pathconf.patch (13 KB)


-- 
https://bugs.ruby-lang.org/