[PATCH] procfs: Fix hardlink counts for /proc/<PID>/task

From: Daniel Drake
Date: Sat Apr 02 2005 - 15:05:43 EST


[ Sorry, sent in the wrong patch. This one should apply with the usual -p1 option. ]

The current logic assumes that a /proc/<PID>/task directory should have a hardlink count of 3, probably counting ".", "..", and a directory for a single child task.

It's fairly obvious that this doesn't work out correctly when a PID has more than one child task, which is quite often the case.

This should fix it up.

Signed-off-by: Daniel Drake <dsd@xxxxxxxxxx> --- linux-2.6.11-gentoo-r5/fs/proc/base.c.orig 2005-04-02 20:47:10.000000000 +0100
+++ linux-2.6.11-gentoo-r5/fs/proc/base.c 2005-04-02 20:51:43.000000000 +0100
@@ -1337,6 +1337,8 @@ static struct file_operations proc_tgid_
static struct inode_operations proc_tgid_attr_inode_operations;
#endif

+static int get_tid_list(int index, unsigned int *tids, struct inode *dir);
+
/* SMP-safe */
static struct dentry *proc_pident_lookup(struct inode *dir,
struct dentry *dentry,
@@ -1376,7 +1378,7 @@ static struct dentry *proc_pident_lookup
*/
switch(p->type) {
case PROC_TGID_TASK:
- inode->i_nlink = 3;
+ inode->i_nlink = 2 + get_tid_list(2, NULL, dir);
inode->i_op = &proc_task_inode_operations;
inode->i_fop = &proc_task_operations;
break;
@@ -1845,7 +1847,8 @@ static int get_tid_list(int index, unsig

if (--index >= 0)
continue;
- tids[nr_tids] = tid;
+ if (tids != NULL)
+ tids[nr_tids] = tid;
nr_tids++;
if (nr_tids >= PROC_MAXPIDS)
break;
@@ -1945,6 +1948,7 @@ static int proc_task_readdir(struct file
}

nr_tids = get_tid_list(pos, tid_array, inode);
+ inode->i_nlink = pos + nr_tids;

for (i = 0; i < nr_tids; i++) {
unsigned long j = PROC_NUMBUF;