Merge 4.4.155 into android-4.4-p

Changes in 4.4.155
	net: 6lowpan: fix reserved space for single frames
	net: mac802154: tx: expand tailroom if necessary
	9p/net: Fix zero-copy path in the 9p virtio transport
	net: lan78xx: Fix misplaced tasklet_schedule() call
	spi: davinci: fix a NULL pointer dereference
	drm/i915/userptr: reject zero user_size
	powerpc/fadump: handle crash memory ranges array index overflow
	powerpc/pseries: Fix endianness while restoring of r3 in MCE handler.
	fs/9p/xattr.c: catch the error of p9_client_clunk when setting xattr failed
	9p/virtio: fix off-by-one error in sg list bounds check
	net/9p/client.c: version pointer uninitialized
	net/9p/trans_fd.c: fix race-condition by flushing workqueue before the kfree()
	x86/mm/pat: Fix L1TF stable backport for CPA, 2nd call
	dm cache metadata: save in-core policy_hint_size to on-disk superblock
	iio: ad9523: Fix displayed phase
	iio: ad9523: Fix return value for ad952x_store()
	vmw_balloon: fix inflation of 64-bit GFNs
	vmw_balloon: do not use 2MB without batching
	vmw_balloon: VMCI_DOORBELL_SET does not check status
	vmw_balloon: fix VMCI use when balloon built into kernel
	tracing: Do not call start/stop() functions when tracing_on does not change
	tracing/blktrace: Fix to allow setting same value
	kthread, tracing: Don't expose half-written comm when creating kthreads
	uprobes: Use synchronize_rcu() not synchronize_sched()
	9p: fix multiple NULL-pointer-dereferences
	PM / sleep: wakeup: Fix build error caused by missing SRCU support
	pnfs/blocklayout: off by one in bl_map_stripe()
	ARM: tegra: Fix Tegra30 Cardhu PCA954x reset
	mm/tlb: Remove tlb_remove_table() non-concurrent condition
	iommu/vt-d: Add definitions for PFSID
	iommu/vt-d: Fix dev iotlb pfsid use
	osf_getdomainname(): use copy_to_user()
	sys: don't hold uts_sem while accessing userspace memory
	userns: move user access out of the mutex
	ubifs: Fix memory leak in lprobs self-check
	Revert "UBIFS: Fix potential integer overflow in allocation"
	ubifs: Check data node size before truncate
	ubifs: Fix synced_i_size calculation for xattr inodes
	pwm: tiehrpwm: Fix disabling of output of PWMs
	fb: fix lost console when the user unplugs a USB adapter
	udlfb: set optimal write delay
	getxattr: use correct xattr length
	bcache: release dc->writeback_lock properly in bch_writeback_thread()
	perf auxtrace: Fix queue resize
	fs/quota: Fix spectre gadget in do_quotactl
	x86/io: add interface to reserve io memtype for a resource range. (v1.1)
	drm/drivers: add support for using the arch wc mapping API.
	Linux 4.4.155

Change-Id: I34f5e28013b2762737e5f0c08b20ae1d0a0f34c0
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

1 files changed, 19 insertions, 20 deletions

diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index 88fefa68c516..a965df4b54f5 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -602,9 +602,26 @@ static ssize_t map_write(struct file *file, const char __user *buf,
 	struct uid_gid_map new_map;
 	unsigned idx;
 	struct uid_gid_extent *extent = NULL;
-	unsigned long page = 0;
+	unsigned long page;
 	char *kbuf, *pos, *next_line;
-	ssize_t ret = -EINVAL;
+	ssize_t ret;
+
+	/* Only allow < page size writes at the beginning of the file */
+	if ((*ppos != 0) || (count >= PAGE_SIZE))
+		return -EINVAL;
+
+	/* Get a buffer */
+	page = __get_free_page(GFP_TEMPORARY);
+	kbuf = (char *) page;
+	if (!page)
+		return -ENOMEM;
+
+	/* Slurp in the user data */
+	if (copy_from_user(kbuf, buf, count)) {
+		free_page(page);
+		return -EFAULT;
+	}
+	kbuf[count] = '\0';
 
 	/*
 	 * The userns_state_mutex serializes all writes to any given map.
@@ -638,24 +655,6 @@ static ssize_t map_write(struct file *file, const char __user *buf,
 	if (cap_valid(cap_setid) && !file_ns_capable(file, ns, CAP_SYS_ADMIN))
 		goto out;
 
-	/* Get a buffer */
-	ret = -ENOMEM;
-	page = __get_free_page(GFP_TEMPORARY);
-	kbuf = (char *) page;
-	if (!page)
-		goto out;
-
-	/* Only allow < page size writes at the beginning of the file */
-	ret = -EINVAL;
-	if ((*ppos != 0) || (count >= PAGE_SIZE))
-		goto out;
-
-	/* Slurp in the user data */
-	ret = -EFAULT;
-	if (copy_from_user(kbuf, buf, count))
-		goto out;
-	kbuf[count] = '\0';
-
 	/* Parse the user data */
 	ret = -EINVAL;
 	pos = kbuf;