lkml.org 
[lkml]   [2004]   [Dec]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectBug_reply : Out of range ptr error in module indicates bug in slab.c
 Hello,
Thanks for ur help. The user will be changing
this using system calls like dup,dup2 etc. If I keep
track of all these modifications by intercepting all
those syscalls and use inode number for identifying
the structure uniquely, will it break?

Thanks,
selva

> nagendran wrote:
> > else {
> > new -> pipe_read_end = fdes[0];
> > new -> pipe_write_end = fdes[1];
>
> this is a bug; fdes is a USERSPACE pointer, you
> cannot directly access
> that from kernel space, you need to use
> copy_from_user() for that.
>
> And note, what you are doing is unreliable, since
> the user is capable of
> changing that information before you log it in your
> structure, so if you
> want to use the data you log for anything security
> related or for
> something that has to be accurate, it's broken...
>
> > while(temp != NULL)
> > {
> > kfree(temp);
> > temp = temp -> next;
> > }
>
> that is of course wrong; you free temp and THEN you
> access it!!
>
>
> -
> To unsubscribe from this list: send the line
> "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at
> http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
>




__________________________________
Do you Yahoo!?
Read only the mail you want - Yahoo! Mail SpamGuard.
http://promotions.yahoo.com/new_mail
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 14:09    [W:0.166 / U:0.040 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site