Merge branch 'akpm' (incoming from Andrew)

Merge second patch-bomb from Andrew Morton:
 - various misc bits
 - the rest of MM
 - add generic fixmap.h, use it
 - backlight updates
 - dynamic_debug updates
 - printk() updates
 - checkpatch updates
 - binfmt_elf
 - ramfs
 - init/
 - autofs4
 - drivers/rtc
 - nilfs
 - hfsplus
 - Documentation/
 - coredump
 - procfs
 - fork
 - exec
 - kexec
 - kdump
 - partitions
 - rapidio
 - rbtree
 - userns
 - memstick
 - w1
 - decompressors

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (197 commits)
  lib/decompress_unlz4.c: always set an error return code on failures
  romfs: fix returm err while getting inode in fill_super
  drivers/w1/masters/w1-gpio.c: add strong pullup emulation
  drivers/memstick/host/rtsx_pci_ms.c: fix ms card data transfer bug
  userns: relax the posix_acl_valid() checks
  arch/sh/kernel/dwarf.c: use rbtree postorder iteration helper instead of solution using repeated rb_erase()
  fs-ext3-use-rbtree-postorder-iteration-helper-instead-of-opencoding-fix
  fs/ext3: use rbtree postorder iteration helper instead of opencoding
  fs/jffs2: use rbtree postorder iteration helper instead of opencoding
  fs/ext4: use rbtree postorder iteration helper instead of opencoding
  fs/ubifs: use rbtree postorder iteration helper instead of opencoding
  net/netfilter/ipset/ip_set_hash_netiface.c: use rbtree postorder iteration instead of opencoding
  rbtree/test: test rbtree_postorder_for_each_entry_safe()
  rbtree/test: move rb_node to the middle of the test struct
  rapidio: add modular rapidio core build into powerpc and mips branches
  partitions/efi: complete documentation of gpt kernel param purpose
  kdump: add /sys/kernel/vmcoreinfo ABI documentation
  kdump: fix exported size of vmcoreinfo note
  kexec: add sysctl to disable kexec_load
  fs/exec.c: call arch_pick_mmap_layout() only once
  ...

7 files changed, 86 insertions, 23 deletions

diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h
index 4218e26df916..acf32054edd8 100644
--- a/fs/autofs4/autofs_i.h
+++ b/fs/autofs4/autofs_i.h
@@ -104,7 +104,7 @@ struct autofs_sb_info {
 	u32 magic;
 	int pipefd;
 	struct file *pipe;
-	pid_t oz_pgrp;
+	struct pid *oz_pgrp;
 	int catatonic;
 	int version;
 	int sub_version;
@@ -140,7 +140,7 @@ static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry)
    filesystem without "magic".) */
 
 static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
-	return sbi->catatonic || task_pgrp_nr(current) == sbi->oz_pgrp;
+	return sbi->catatonic || task_pgrp(current) == sbi->oz_pgrp;
 }
 
 /* Does a dentry have some pending activity? */
diff --git a/fs/autofs4/dev-ioctl.c b/fs/autofs4/dev-ioctl.c
index 1818ce7f5a06..3182c0e68b42 100644
--- a/fs/autofs4/dev-ioctl.c
+++ b/fs/autofs4/dev-ioctl.c
@@ -346,6 +346,7 @@ static int autofs_dev_ioctl_setpipefd(struct file *fp,
 {
 	int pipefd;
 	int err = 0;
+	struct pid *new_pid = NULL;
 
 	if (param->setpipefd.pipefd == -1)
 		return -EINVAL;
@@ -357,7 +358,17 @@ static int autofs_dev_ioctl_setpipefd(struct file *fp,
 		mutex_unlock(&sbi->wq_mutex);
 		return -EBUSY;
 	} else {
-		struct file *pipe = fget(pipefd);
+		struct file *pipe;
+
+		new_pid = get_task_pid(current, PIDTYPE_PGID);
+
+		if (ns_of_pid(new_pid) != ns_of_pid(sbi->oz_pgrp)) {
+			AUTOFS_WARN("Not allowed to change PID namespace");
+			err = -EINVAL;
+			goto out;
+		}
+
+		pipe = fget(pipefd);
 		if (!pipe) {
 			err = -EBADF;
 			goto out;
@@ -367,12 +378,13 @@ static int autofs_dev_ioctl_setpipefd(struct file *fp,
 			fput(pipe);
 			goto out;
 		}
-		sbi->oz_pgrp = task_pgrp_nr(current);
+		swap(sbi->oz_pgrp, new_pid);
 		sbi->pipefd = pipefd;
 		sbi->pipe = pipe;
 		sbi->catatonic = 0;
 	}
 out:
+	put_pid(new_pid);
 	mutex_unlock(&sbi->wq_mutex);
 	return err;
 }
diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c
index 3d9d3f5d5dda..394e90b02c5e 100644
--- a/fs/autofs4/expire.c
+++ b/fs/autofs4/expire.c
@@ -402,6 +402,20 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,
 			goto next;
 		}
 
+		if (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode)) {
+			DPRINTK("checking symlink %p %.*s",
+				dentry, (int)dentry->d_name.len, dentry->d_name.name);
+			/*
+			 * A symlink can't be "busy" in the usual sense so
+			 * just check last used for expire timeout.
+			 */
+			if (autofs4_can_expire(dentry, timeout, do_now)) {
+				expired = dentry;
+				goto found;
+			}
+			goto next;
+		}
+
 		if (simple_empty(dentry))
 			goto next;
 
diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c
index 3b9cc9b973c2..d7bd395ab586 100644
--- a/fs/autofs4/inode.c
+++ b/fs/autofs4/inode.c
@@ -56,8 +56,11 @@ void autofs4_kill_sb(struct super_block *sb)
 	 * just call kill_anon_super when we are called from
 	 * deactivate_super.
 	 */
-	if (sbi) /* Free wait queues, close pipe */
+	if (sbi) {
+		/* Free wait queues, close pipe */
 		autofs4_catatonic_mode(sbi);
+		put_pid(sbi->oz_pgrp);
+	}
 
 	DPRINTK("shutting down");
 	kill_litter_super(sb);
@@ -80,7 +83,7 @@ static int autofs4_show_options(struct seq_file *m, struct dentry *root)
 	if (!gid_eq(root_inode->i_gid, GLOBAL_ROOT_GID))
 		seq_printf(m, ",gid=%u",
 			from_kgid_munged(&init_user_ns, root_inode->i_gid));
-	seq_printf(m, ",pgrp=%d", sbi->oz_pgrp);
+	seq_printf(m, ",pgrp=%d", pid_vnr(sbi->oz_pgrp));
 	seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ);
 	seq_printf(m, ",minproto=%d", sbi->min_proto);
 	seq_printf(m, ",maxproto=%d", sbi->max_proto);
@@ -124,7 +127,8 @@ static const match_table_t tokens = {
 };
 
 static int parse_options(char *options, int *pipefd, kuid_t *uid, kgid_t *gid,
-		pid_t *pgrp, unsigned int *type, int *minproto, int *maxproto)
+			 int *pgrp, bool *pgrp_set, unsigned int *type,
+			 int *minproto, int *maxproto)
 {
 	char *p;
 	substring_t args[MAX_OPT_ARGS];
@@ -132,7 +136,6 @@ static int parse_options(char *options, int *pipefd, kuid_t *uid, kgid_t *gid,
 
 	*uid = current_uid();
 	*gid = current_gid();
-	*pgrp = task_pgrp_nr(current);
 
 	*minproto = AUTOFS_MIN_PROTO_VERSION;
 	*maxproto = AUTOFS_MAX_PROTO_VERSION;
@@ -171,6 +174,7 @@ static int parse_options(char *options, int *pipefd, kuid_t *uid, kgid_t *gid,
 			if (match_int(args, &option))
 				return 1;
 			*pgrp = option;
+			*pgrp_set = true;
 			break;
 		case Opt_minproto:
 			if (match_int(args, &option))
@@ -206,10 +210,13 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
 	int pipefd;
 	struct autofs_sb_info *sbi;
 	struct autofs_info *ino;
+	int pgrp;
+	bool pgrp_set = false;
+	int ret = -EINVAL;
 
 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 	if (!sbi)
-		goto fail_unlock;
+		return -ENOMEM;
 	DPRINTK("starting up, sbi = %p",sbi);
 
 	s->s_fs_info = sbi;
@@ -218,7 +225,7 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
 	sbi->pipe = NULL;
 	sbi->catatonic = 1;
 	sbi->exp_timeout = 0;
-	sbi->oz_pgrp = task_pgrp_nr(current);
+	sbi->oz_pgrp = NULL;
 	sbi->sb = s;
 	sbi->version = 0;
 	sbi->sub_version = 0;
@@ -243,8 +250,10 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
 	 * Get the root inode and dentry, but defer checking for errors.
 	 */
 	ino = autofs4_new_ino(sbi);
-	if (!ino)
+	if (!ino) {
+		ret = -ENOMEM;
 		goto fail_free;
+	}
 	root_inode = autofs4_get_inode(s, S_IFDIR | 0755);
 	root = d_make_root(root_inode);
 	if (!root)
@@ -255,12 +264,23 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
 
 	/* Can this call block? */
 	if (parse_options(data, &pipefd, &root_inode->i_uid, &root_inode->i_gid,
-				&sbi->oz_pgrp, &sbi->type, &sbi->min_proto,
-				&sbi->max_proto)) {
+			  &pgrp, &pgrp_set, &sbi->type, &sbi->min_proto,
+			  &sbi->max_proto)) {
 		printk("autofs: called with bogus options\n");
 		goto fail_dput;
 	}
 
+	if (pgrp_set) {
+		sbi->oz_pgrp = find_get_pid(pgrp);
+		if (!sbi->oz_pgrp) {
+			pr_warn("autofs: could not find process group %d\n",
+				pgrp);
+			goto fail_dput;
+		}
+	} else {
+		sbi->oz_pgrp = get_task_pid(current, PIDTYPE_PGID);
+	}
+
 	if (autofs_type_trigger(sbi->type))
 		__managed_dentry_set_managed(root);
 
@@ -284,14 +304,15 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
 		sbi->version = sbi->max_proto;
 	sbi->sub_version = AUTOFS_PROTO_SUBVERSION;
 
-	DPRINTK("pipe fd = %d, pgrp = %u", pipefd, sbi->oz_pgrp);
+	DPRINTK("pipe fd = %d, pgrp = %u", pipefd, pid_nr(sbi->oz_pgrp));
 	pipe = fget(pipefd);
-	
+
 	if (!pipe) {
 		printk("autofs: could not open pipe file descriptor\n");
 		goto fail_dput;
 	}
-	if (autofs_prepare_pipe(pipe) < 0)
+	ret = autofs_prepare_pipe(pipe);
+	if (ret < 0)
 		goto fail_fput;
 	sbi->pipe = pipe;
 	sbi->pipefd = pipefd;
@@ -316,10 +337,10 @@ fail_dput:
 fail_ino:
 	kfree(ino);
 fail_free:
+	put_pid(sbi->oz_pgrp);
 	kfree(sbi);
 	s->s_fs_info = NULL;
-fail_unlock:
-	return -EINVAL;
+	return ret;
 }
 
 struct inode *autofs4_get_inode(struct super_block *sb, umode_t mode)
diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index 92ef341ba0cf..2caf36ac3e93 100644
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -558,7 +558,7 @@ static int autofs4_dir_symlink(struct inode *dir,
 	dget(dentry);
 	atomic_inc(&ino->count);
 	p_ino = autofs4_dentry_ino(dentry->d_parent);
-	if (p_ino && dentry->d_parent != dentry)
+	if (p_ino && !IS_ROOT(dentry))
 		atomic_inc(&p_ino->count);
 
 	dir->i_mtime = CURRENT_TIME;
@@ -593,7 +593,7 @@ static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry)
 
 	if (atomic_dec_and_test(&ino->count)) {
 		p_ino = autofs4_dentry_ino(dentry->d_parent);
-		if (p_ino && dentry->d_parent != dentry)
+		if (p_ino && !IS_ROOT(dentry))
 			atomic_dec(&p_ino->count);
 	}
 	dput(ino->dentry);
@@ -732,7 +732,7 @@ static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, umode_t m
 	dget(dentry);
 	atomic_inc(&ino->count);
 	p_ino = autofs4_dentry_ino(dentry->d_parent);
-	if (p_ino && dentry->d_parent != dentry)
+	if (p_ino && !IS_ROOT(dentry))
 		atomic_inc(&p_ino->count);
 	inc_nlink(dir);
 	dir->i_mtime = CURRENT_TIME;
diff --git a/fs/autofs4/symlink.c b/fs/autofs4/symlink.c
index f27c094a1919..1e8ea192be2b 100644
--- a/fs/autofs4/symlink.c
+++ b/fs/autofs4/symlink.c
@@ -14,6 +14,10 @@
 
 static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd)
 {
+	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+	struct autofs_info *ino = autofs4_dentry_ino(dentry);
+	if (ino && !autofs4_oz_mode(sbi))
+		ino->last_used = jiffies;
 	nd_set_link(nd, dentry->d_inode->i_private);
 	return NULL;
 }
diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c
index 689e40d983ad..116fd38ee472 100644
--- a/fs/autofs4/waitq.c
+++ b/fs/autofs4/waitq.c
@@ -347,11 +347,23 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
 	struct qstr qstr;
 	char *name;
 	int status, ret, type;
+	pid_t pid;
+	pid_t tgid;
 
 	/* In catatonic mode, we don't wait for nobody */
 	if (sbi->catatonic)
 		return -ENOENT;
 
+	/*
+	 * Try translating pids to the namespace of the daemon.
+	 *
+	 * Zero means failure: we are in an unrelated pid namespace.
+	 */
+	pid = task_pid_nr_ns(current, ns_of_pid(sbi->oz_pgrp));
+	tgid = task_tgid_nr_ns(current, ns_of_pid(sbi->oz_pgrp));
+	if (pid == 0 || tgid == 0)
+		return -ENOENT;
+
 	if (!dentry->d_inode) {
 		/*
 		 * A wait for a negative dentry is invalid for certain
@@ -417,8 +429,8 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
 		wq->ino = autofs4_get_ino(sbi);
 		wq->uid = current_uid();
 		wq->gid = current_gid();
-		wq->pid = current->pid;
-		wq->tgid = current->tgid;
+		wq->pid = pid;
+		wq->tgid = tgid;
 		wq->status = -EINTR; /* Status return if interrupted */
 		wq->wait_ctr = 2;