| From d8bdc59f215e62098bc5b4256fd9928bf27053a1 Mon Sep 17 00:00:00 2001 |
| From: Linus Torvalds <torvalds@linux-foundation.org> |
| Date: Mon, 18 Apr 2011 10:36:54 -0700 |
| Subject: proc: do proper range check on readdir offset |
| |
| From: Linus Torvalds <torvalds@linux-foundation.org> |
| |
| 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: Greg Kroah-Hartman <gregkh@suse.de> |
| |
| --- |
| fs/proc/base.c | 9 +++++++-- |
| 1 file changed, 7 insertions(+), 2 deletions(-) |
| |
| --- a/fs/proc/base.c |
| +++ b/fs/proc/base.c |
| @@ -2872,11 +2872,16 @@ static int proc_pid_fill_cache(struct fi |
| /* 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; |
| |
