lkml.org 
[lkml]   [2002]   [Dec]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectPROBLEM
Hi all,

I found a bug that cause the kernel to lockup.

The problem is in mm/shmem.c do_shmem_file_read() (the tmpfs)

at line 959 there is a call to file_read_actor(desc, page, offset, nr);

The problem is that inside the function file_read_actor() desc->error is
set to -EFAULT (this happens when the buffer supplied by the user for the
read is wrong)
but there is no check right after the return from file_read_actor() to
test this situation.

The result is that the desc->count field always stay the same and the
while loop in do_shmem_file_read never end and the kernel locksup.

The fix is very simple just add the following line after the call to
file_read_actor():

-------------------
if(desc->error)
break
-------------------


If you need any other info please mail me

Regards

--lior


________________________________________________________________
Lior Amar Distributed Computing Lab MOSIX
E-mail : lior@cs.huji.ac.il
________________________________________________________________

-
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 13:32    [W:0.041 / U:2.612 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site