Merge 4.4.295 into android-4.4-p

Changes in 4.4.295
	HID: introduce hid_is_using_ll_driver
	HID: add hid_is_usb() function to make it simpler for USB detection
	HID: add USB_HID dependancy to hid-prodikeys
	HID: add USB_HID dependancy to hid-chicony
	HID: add USB_HID dependancy on some USB HID drivers
	HID: wacom: fix problems when device is not a valid USB device
	HID: check for valid USB device for many HID drivers
	can: sja1000: fix use after free in ems_pcmcia_add_card()
	nfc: fix potential NULL pointer deref in nfc_genl_dump_ses_done
	mm: bdi: initialize bdi_min_ratio when bdi is unregistered
	ALSA: ctl: Fix copy of updated id with element read/write
	ALSA: pcm: oss: Fix negative period/buffer sizes
	ALSA: pcm: oss: Limit the period size to 16MB
	ALSA: pcm: oss: Handle missing errors in snd_pcm_oss_change_params*()
	tracefs: Have new files inherit the ownership of their parent
	can: pch_can: pch_can_rx_normal: fix use after free
	libata: add horkage for ASMedia 1092
	wait: add wake_up_pollfree()
	binder: use wake_up_pollfree()
	signalfd: use wake_up_pollfree()
	tracefs: Set all files to the same group ownership as the mount option
	block: fix ioprio_get(IOPRIO_WHO_PGRP) vs setuid(2)
	net: cdc_ncm: Allow for dwNtbOutMaxSize to be unset or zero
	net: altera: set a couple error code in probe()
	net: fec: only clear interrupt of handling queue in fec_enet_rx_queue()
	net, neigh: clear whole pneigh_entry at alloc time
	net/qla3xxx: fix an error code in ql_adapter_up()
	USB: gadget: detect too-big endpoint 0 requests
	USB: gadget: zero allocate endpoint 0 buffers
	usb: core: config: fix validation of wMaxPacketValue entries
	iio: stk3310: Don't return error code in interrupt handler
	iio: mma8452: Fix trigger reference couting
	iio: ltr501: Don't return error code in trigger handler
	iio: itg3200: Call iio_trigger_notify_done() on error
	iio: accel: kxcjk-1013: Fix possible memory leak in probe and remove
	irqchip/irq-gic-v3-its.c: Force synchronisation when issuing INVALL
	irqchip: nvic: Fix offset for Interrupt Priority Offsets
	Linux 4.4.295

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I4810f7e2ebd538739fb0d62f9eade0921a9badfb

1 files changed, 76 insertions, 0 deletions

diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c
index 6ccfd47157d3..2914220e975c 100644
--- a/fs/tracefs/inode.c
+++ b/fs/tracefs/inode.c
@@ -162,6 +162,77 @@ struct tracefs_fs_info {
 	struct tracefs_mount_opts mount_opts;
 };
 
+static void change_gid(struct dentry *dentry, kgid_t gid)
+{
+	if (!dentry->d_inode)
+		return;
+	dentry->d_inode->i_gid = gid;
+}
+
+/*
+ * Taken from d_walk, but without he need for handling renames.
+ * Nothing can be renamed while walking the list, as tracefs
+ * does not support renames. This is only called when mounting
+ * or remounting the file system, to set all the files to
+ * the given gid.
+ */
+static void set_gid(struct dentry *parent, kgid_t gid)
+{
+	struct dentry *this_parent;
+	struct list_head *next;
+
+	this_parent = parent;
+	spin_lock(&this_parent->d_lock);
+
+	change_gid(this_parent, gid);
+repeat:
+	next = this_parent->d_subdirs.next;
+resume:
+	while (next != &this_parent->d_subdirs) {
+		struct list_head *tmp = next;
+		struct dentry *dentry = list_entry(tmp, struct dentry, d_child);
+		next = tmp->next;
+
+		spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
+
+		change_gid(dentry, gid);
+
+		if (!list_empty(&dentry->d_subdirs)) {
+			spin_unlock(&this_parent->d_lock);
+			spin_release(&dentry->d_lock.dep_map, 1, _RET_IP_);
+			this_parent = dentry;
+			spin_acquire(&this_parent->d_lock.dep_map, 0, 1, _RET_IP_);
+			goto repeat;
+		}
+		spin_unlock(&dentry->d_lock);
+	}
+	/*
+	 * All done at this level ... ascend and resume the search.
+	 */
+	rcu_read_lock();
+ascend:
+	if (this_parent != parent) {
+		struct dentry *child = this_parent;
+		this_parent = child->d_parent;
+
+		spin_unlock(&child->d_lock);
+		spin_lock(&this_parent->d_lock);
+
+		/* go into the first sibling still alive */
+		do {
+			next = child->d_child.next;
+			if (next == &this_parent->d_subdirs)
+				goto ascend;
+			child = list_entry(next, struct dentry, d_child);
+		} while (unlikely(child->d_flags & DCACHE_DENTRY_KILLED));
+		rcu_read_unlock();
+		goto resume;
+	}
+	rcu_read_unlock();
+	spin_unlock(&this_parent->d_lock);
+	return;
+}
+
 static int tracefs_parse_options(char *data, struct tracefs_mount_opts *opts)
 {
 	substring_t args[MAX_OPT_ARGS];
@@ -194,6 +265,7 @@ static int tracefs_parse_options(char *data, struct tracefs_mount_opts *opts)
 			if (!gid_valid(gid))
 				return -EINVAL;
 			opts->gid = gid;
+			set_gid(tracefs_mount->mnt_root, gid);
 			break;
 		case Opt_mode:
 			if (match_octal(&args[0], &option))
@@ -411,6 +483,8 @@ struct dentry *tracefs_create_file(const char *name, umode_t mode,
 	inode->i_mode = mode;
 	inode->i_fop = fops ? fops : &tracefs_file_operations;
 	inode->i_private = data;
+	inode->i_uid = d_inode(dentry->d_parent)->i_uid;
+	inode->i_gid = d_inode(dentry->d_parent)->i_gid;
 	d_instantiate(dentry, inode);
 	fsnotify_create(dentry->d_parent->d_inode, dentry);
 	return end_creating(dentry);
@@ -433,6 +507,8 @@ static struct dentry *__create_dir(const char *name, struct dentry *parent,
 	inode->i_mode = S_IFDIR | S_IRWXU | S_IRUSR| S_IRGRP | S_IXUSR | S_IXGRP;
 	inode->i_op = ops;
 	inode->i_fop = &simple_dir_operations;
+	inode->i_uid = d_inode(dentry->d_parent)->i_uid;
+	inode->i_gid = d_inode(dentry->d_parent)->i_gid;
 
 	/* directory inodes start off with i_nlink == 2 (for "." entry) */
 	inc_nlink(inode);