linux-kernel - Walking User mode pages

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 linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:	Thu, 28 Feb 2008 08:41:44 -0600
From:	YM Yen <yminyen@...il.com>
To:	linux-kernel@...r.kernel.org
Subject: Walking User mode pages

hi,

I am a newbie to Linux kernel, so please forgive me if the question is
stupid.

To understand the swapping system, I decided to write a module to scan 
every task_struct using for_each_process() checking whether or not the 
page pointed by the pte is swapped out. To get the linear address 
address of the pte, I did something similar to "pgd_offset << 
PGDIR_SHIFT + pud_offset << PUD_SHIFT + pmd_offset << PMDSHIFT + 
pte_offset << PAGE_SHIFT". The offset for each level is simply the 
iteration of the walking of the table ranging from 0 to PTRS_PER_(PGD, 
PUD, PMD, PTE) depending on the table. However, the result of the 
calculation doesn't match anything in the /proc/<pid>/maps.

Is this to be expected? If that's the case, how can I find out what's in 
the swap file. Thanks in advance.

YM
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/