From: ebiederm@xmission.com (Eric W. Biederman) Long ago when the CLONE_THREAD support first went it someone thought it would be wise to point /proc/self at /proc/ instead of /proc/. Given that /proc/ can return information about a very different task (if enough things have been unshared) then our current process /proc/ seems blatantly wrong. So far I have yet to think up an example where the current behavior would be advantageous, and I can see several places where it is seriously non-intuitive. We may be stuck with the current broken behavior for backwards compatibility reasons but lets try fixing our ancient bug for the 2.6.25 time frame and see if anyone screams. Signed-off-by: Eric W. Biederman Acked-by: Ingo Molnar Cc: "Guillaume Chazarain" Cc: "Pavel Emelyanov" Cc: "Rafael J. Wysocki" Cc: Oleg Nesterov Cc: Roland McGrath Signed-off-by: Andrew Morton --- fs/proc/base.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff -puN fs/proc/base.c~proc-fix-the-threaded-proc-self fs/proc/base.c --- a/fs/proc/base.c~proc-fix-the-threaded-proc-self +++ a/fs/proc/base.c @@ -2003,22 +2003,22 @@ static int proc_self_readlink(struct den int buflen) { struct pid_namespace *ns = dentry->d_sb->s_fs_info; - pid_t tgid = task_tgid_nr_ns(current, ns); + pid_t pid = task_pid_nr_ns(current, ns); char tmp[PROC_NUMBUF]; - if (!tgid) + if (!pid) return -ENOENT; - sprintf(tmp, "%d", tgid); + sprintf(tmp, "%d", pid); return vfs_readlink(dentry,buffer,buflen,tmp); } static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) { struct pid_namespace *ns = dentry->d_sb->s_fs_info; - pid_t tgid = task_tgid_nr_ns(current, ns); + pid_t pid = task_pid_nr_ns(current, ns); char tmp[PROC_NUMBUF]; - if (!tgid) + if (!pid) return ERR_PTR(-ENOENT); - sprintf(tmp, "%d", task_tgid_nr_ns(current, ns)); + sprintf(tmp, "%d", pid); return ERR_PTR(vfs_follow_link(nd,tmp)); } _