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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-04-18 10:36:54 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-04-22 08:50:03 -0700 |
| commit | 968b9098cac22e2a05f27a334067c9bb75121bd9 (patch) | |
| tree | abbf5bf4da5ebd834e2dc7317816b98fde581c19 | |
| parent | 56aaabf6651ebf8f59995b1a5166df598c08411b (diff) | |
| download | lwn-968b9098cac22e2a05f27a334067c9bb75121bd9.tar.gz lwn-968b9098cac22e2a05f27a334067c9bb75121bd9.zip | |
proc: do proper range check on readdir offset
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>
| -rw-r--r-- | fs/proc/base.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c index 8dce96c331f8..65053a1ad043 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2872,11 +2872,16 @@ 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; |