diff options
authorLinus Torvalds <torvalds@linux-foundation.org>2011-04-18 10:36:54 -0700
committerGreg Kroah-Hartman <gregkh@suse.de>2011-04-22 08:50:03 -0700
commit968b9098cac22e2a05f27a334067c9bb75121bd9 (patch)
parent56aaabf6651ebf8f59995b1a5166df598c08411b (diff)
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>
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;