lkml.org 
[lkml]   [2012]   [Mar]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[34-longterm 081/196] proc: do proper range check on readdir offset
Date
From: Linus Torvalds <torvalds@linux-foundation.org>

-------------------
This is a commit scheduled for the next v2.6.34 longterm release.
If you see a problem with using this for longterm, please comment.
-------------------

commit d8bdc59f215e62098bc5b4256fd9928bf27053a1 upstream.

Rather than pass in some random truncated offset to the pid-related
functions, check that the offset is in range up-front.

This is just cleanup, the previous commit fixed the real problem.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---
fs/proc/base.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 8418fcc..268f00d 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2871,11 +2871,16 @@ static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldi
/* for the /proc/ directory itself, after non-process stuff has been done */
int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
{
- unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
- struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode);
+ unsigned int nr;
+ struct task_struct *reaper;
struct tgid_iter iter;
struct pid_namespace *ns;

+ if (filp->f_pos >= PID_MAX_LIMIT + TGID_OFFSET)
+ goto out_no_task;
+ nr = filp->f_pos - FIRST_PROCESS_ENTRY;
+
+ reaper = get_proc_task(filp->f_path.dentry->d_inode);
if (!reaper)
goto out_no_task;

--
1.7.9.3


\
 
 \ /
  Last update: 2012-03-13 01:59    [W:0.628 / U:0.256 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site