lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:   Fri, 20 Nov 2020 11:44:12 -0500
From:   Alan Stern <stern@...land.harvard.edu>
To:     Petr Mladek <pmladek@...e.com>,
        Steven Rostedt <rostedt@...dmis.org>,
        Sergey Senozhatsky <sergey.senozhatsky@...il.com>
Cc:     Kernel development list <linux-kernel@...r.kernel.org>
Subject: Printk specifiers for __user pointers

To the VSPRINTF maintainers:

Documentation/core-api/printk-formats.rst lists a large number of format 
specifiers for pointers of various sorts.  Yet as far as I can see, 
there is no specifier meant for use with __user pointers.

The security implications of printing the true, unmangled value of a 
__user pointer are minimal, since doing so does not leak any kernel 
information.  So %px would work, but tools like checkpatch.pl don't like 
it.

Should a new specifier be added?  If not, should we simply use %px?

Alan Stern

Powered by blists - more mailing lists