From f7ad3c6be90809b53b7f0ae9d4eaa45ce2564a79 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Tue, 10 Aug 2010 11:41:36 +0200 Subject: vfs: add helpers to get root and pwd Add three helpers that retrieve a refcounted copy of the root and cwd from the supplied fs_struct. get_fs_root() get_fs_pwd() get_fs_root_and_pwd() Signed-off-by: Miklos Szeredi Signed-off-by: Al Viro --- fs/proc/base.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) (limited to 'fs/proc') diff --git a/fs/proc/base.c b/fs/proc/base.c index c806dfb..4cf5abf 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -149,18 +149,13 @@ static unsigned int pid_entry_count_dirs(const struct pid_entry *entries, return count; } -static int get_fs_path(struct task_struct *task, struct path *path, bool root) +static int get_task_root(struct task_struct *task, struct path *root) { - struct fs_struct *fs; int result = -ENOENT; task_lock(task); - fs = task->fs; - if (fs) { - read_lock(&fs->lock); - *path = root ? fs->root : fs->pwd; - path_get(path); - read_unlock(&fs->lock); + if (task->fs) { + get_fs_root(task->fs, root); result = 0; } task_unlock(task); @@ -173,7 +168,12 @@ static int proc_cwd_link(struct inode *inode, struct path *path) int result = -ENOENT; if (task) { - result = get_fs_path(task, path, 0); + task_lock(task); + if (task->fs) { + get_fs_pwd(task->fs, path); + result = 0; + } + task_unlock(task); put_task_struct(task); } return result; @@ -185,7 +185,7 @@ static int proc_root_link(struct inode *inode, struct path *path) int result = -ENOENT; if (task) { - result = get_fs_path(task, path, 1); + result = get_task_root(task, path); put_task_struct(task); } return result; @@ -597,7 +597,7 @@ static int mounts_open_common(struct inode *inode, struct file *file, get_mnt_ns(ns); } rcu_read_unlock(); - if (ns && get_fs_path(task, &root, 1) == 0) + if (ns && get_task_root(task, &root) == 0) ret = 0; put_task_struct(task); } -- cgit v1.1 From 8df9d1a4142311c084ffeeacb67cd34d190eff74 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Tue, 10 Aug 2010 11:41:41 +0200 Subject: vfs: show unreachable paths in getcwd and proc Prepend "(unreachable)" to path strings if the path is not reachable from the current root. Two places updated are - the return string from getcwd() - and symlinks under /proc/$PID. Other uses of d_path() are left unchanged (we know that some old software crashes if /proc/mounts is changed). Signed-off-by: Miklos Szeredi Signed-off-by: Al Viro --- fs/proc/base.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/proc') diff --git a/fs/proc/base.c b/fs/proc/base.c index 4cf5abf..a1c43e7 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1526,7 +1526,7 @@ static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) if (!tmp) return -ENOMEM; - pathname = d_path(path, tmp, PAGE_SIZE); + pathname = d_path_with_unreachable(path, tmp, PAGE_SIZE); len = PTR_ERR(pathname); if (IS_ERR(pathname)) goto out; -- cgit v1.1