From: Lafcadio Wluiki Date: Fri, 24 Feb 2017 23:00:23 +0000 (-0800) Subject: procfs: use an enum for possible hidepid values X-Git-Tag: v4.11-rc1~76^2~27 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=796f571b0c5cf3efd2f652779770fa7bbbc2bb03;p=linux.git procfs: use an enum for possible hidepid values Previously, the hidepid parameter was checked by comparing literal integers 0, 1, 2. Let's add a proper enum for this, to make the checking more expressive: 0 → HIDEPID_OFF 1 → HIDEPID_NO_ACCESS 2 → HIDEPID_INVISIBLE This changes the internal labelling only, the userspace-facing interface remains unmodified, and still works with literal integers 0, 1, 2. No functional changes. Link: http://lkml.kernel.org/r/1484572984-13388-2-git-send-email-djalal@gmail.com Signed-off-by: Lafcadio Wluiki Signed-off-by: Djalal Harouni Acked-by: Kees Cook Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/fs/proc/base.c b/fs/proc/base.c index 4ecb5edc3c61..b8f06273353e 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -697,11 +697,11 @@ static int proc_pid_permission(struct inode *inode, int mask) task = get_proc_task(inode); if (!task) return -ESRCH; - has_perms = has_pid_permissions(pid, task, 1); + has_perms = has_pid_permissions(pid, task, HIDEPID_NO_ACCESS); put_task_struct(task); if (!has_perms) { - if (pid->hide_pid == 2) { + if (pid->hide_pid == HIDEPID_INVISIBLE) { /* * Let's make getdents(), stat(), and open() * consistent with each other. If a process @@ -1737,7 +1737,7 @@ int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) stat->gid = GLOBAL_ROOT_GID; task = pid_task(proc_pid(inode), PIDTYPE_PID); if (task) { - if (!has_pid_permissions(pid, task, 2)) { + if (!has_pid_permissions(pid, task, HIDEPID_INVISIBLE)) { rcu_read_unlock(); /* * This doesn't prevent learning whether PID exists, @@ -3168,7 +3168,7 @@ int proc_pid_readdir(struct file *file, struct dir_context *ctx) int len; cond_resched(); - if (!has_pid_permissions(ns, iter.task, 2)) + if (!has_pid_permissions(ns, iter.task, HIDEPID_INVISIBLE)) continue; len = snprintf(name, sizeof(name), "%d", iter.tgid); diff --git a/fs/proc/inode.c b/fs/proc/inode.c index 7ad9ed7958af..2cc7a8030275 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -107,7 +107,7 @@ static int proc_show_options(struct seq_file *seq, struct dentry *root) if (!gid_eq(pid->pid_gid, GLOBAL_ROOT_GID)) seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, pid->pid_gid)); - if (pid->hide_pid != 0) + if (pid->hide_pid != HIDEPID_OFF) seq_printf(seq, ",hidepid=%u", pid->hide_pid); return 0; diff --git a/fs/proc/root.c b/fs/proc/root.c index 1988440b2049..b90da888b81a 100644 --- a/fs/proc/root.c +++ b/fs/proc/root.c @@ -58,7 +58,8 @@ int proc_parse_options(char *options, struct pid_namespace *pid) case Opt_hidepid: if (match_int(&args[0], &option)) return 0; - if (option < 0 || option > 2) { + if (option < HIDEPID_OFF || + option > HIDEPID_INVISIBLE) { pr_err("proc: hidepid value must be between 0 and 2.\n"); return 0; } diff --git a/include/linux/pid_namespace.h b/include/linux/pid_namespace.h index 34cce96741bc..c2a989dee876 100644 --- a/include/linux/pid_namespace.h +++ b/include/linux/pid_namespace.h @@ -21,6 +21,12 @@ struct pidmap { struct fs_pin; +enum { /* definitions for pid_namespace's hide_pid field */ + HIDEPID_OFF = 0, + HIDEPID_NO_ACCESS = 1, + HIDEPID_INVISIBLE = 2, +}; + struct pid_namespace { struct kref kref; struct pidmap pidmap[PIDMAP_ENTRIES];