Merge 4.4.294 into android-4.4-p

Changes in 4.4.294
	staging: ion: Prevent incorrect reference counting behavour
	USB: serial: option: add Telit LE910S1 0x9200 composition
	USB: serial: option: add Fibocom FM101-GL variants
	usb: hub: Fix usb enumeration issue due to address0 race
	usb: hub: Fix locking issues with address0_mutex
	binder: fix test regression due to sender_euid change
	ALSA: ctxfi: Fix out-of-range access
	staging: rtl8192e: Fix use after free in _rtl92e_pci_disconnect()
	xen: don't continue xenstore initialization in case of errors
	xen: detect uninitialized xenbus in xenbus_init
	ARM: dts: BCM5301X: Add interrupt properties to GPIO node
	ASoC: topology: Add missing rwsem around snd_ctl_remove() calls
	net: ieee802154: handle iftypes as u32
	NFSv42: Don't fail clone() unless the OP_CLONE operation failed
	ARM: socfpga: Fix crash with CONFIG_FORTIRY_SOURCE
	scsi: mpt3sas: Fix kernel panic during drive powercycle test
	tcp_cubic: fix spurious Hystart ACK train detections for not-cwnd-limited flows
	tracing: Check pid filtering when creating events
	hugetlbfs: flush TLBs correctly after huge_pmd_unshare
	proc/vmcore: fix clearing user buffer by properly using clear_user()
	NFC: add NCI_UNREG flag to eliminate the race
	fuse: fix page stealing
	fuse: release pipe buf after last use
	shm: extend forced shm destroy to support objects from several IPC nses
	xen: sync include/xen/interface/io/ring.h with Xen's newest version
	xen/blkfront: read response from backend only once
	xen/blkfront: don't take local copy of a request from the ring page
	xen/blkfront: don't trust the backend response data blindly
	xen/netfront: read response from backend only once
	xen/netfront: don't read data from request on the ring page
	xen/netfront: disentangle tx_skb_freelist
	xen/netfront: don't trust the backend response data blindly
	tty: hvc: replace BUG_ON() with negative return value
	hugetlb: take PMD sharing into account when flushing tlb/caches
	net: return correct error code
	platform/x86: thinkpad_acpi: Fix WWAN device disabled issue after S3 deep
	s390/setup: avoid using memblock_enforce_memory_limit
	scsi: iscsi: Unblock session then wake up error handler
	net: tulip: de4x5: fix the problem that the array 'lp->phy[8]' may be out of bound
	net: ethernet: dec: tulip: de4x5: fix possible array overflows in type3_infoblock()
	kprobes: Limit max data_size of the kretprobe instances
	sata_fsl: fix UAF in sata_fsl_port_stop when rmmod sata_fsl
	sata_fsl: fix warning in remove_proc_entry when rmmod sata_fsl
	fs: add fget_many() and fput_many()
	fget: check that the fd still exists after getting a ref to it
	natsemi: xtensa: fix section mismatch warnings
	net: qlogic: qlcnic: Fix a NULL pointer dereference in qlcnic_83xx_add_rings()
	siphash: use _unaligned version by default
	parisc: Fix "make install" on newer debian releases
	vgacon: Propagate console boot parameters before calling `vc_resize'
	tty: serial: msm_serial: Deactivate RX DMA for polling support
	serial: pl011: Add ACPI SBSA UART match id
	Linux 4.4.294

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Id3cafc33da957a0501bcf61d000025167d552797

1 files changed, 14 insertions, 5 deletions

diff --git a/fs/file.c b/fs/file.c
index 090015401c55..0ed602e1fbd2 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -691,7 +691,7 @@ void do_close_on_exec(struct files_struct *files)
 	spin_unlock(&files->file_lock);
 }
 
-static struct file *__fget(unsigned int fd, fmode_t mask)
+static struct file *__fget(unsigned int fd, fmode_t mask, unsigned int refs)
 {
 	struct files_struct *files = current->files;
 	struct file *file;
@@ -706,23 +706,32 @@ loop:
 		 */
 		if (file->f_mode & mask)
 			file = NULL;
-		else if (!get_file_rcu(file))
+		else if (!get_file_rcu_many(file, refs))
 			goto loop;
+		else if (__fcheck_files(files, fd) != file) {
+			fput_many(file, refs);
+			goto loop;
+		}
 	}
 	rcu_read_unlock();
 
 	return file;
 }
 
+struct file *fget_many(unsigned int fd, unsigned int refs)
+{
+	return __fget(fd, FMODE_PATH, refs);
+}
+
 struct file *fget(unsigned int fd)
 {
-	return __fget(fd, FMODE_PATH);
+	return __fget(fd, FMODE_PATH, 1);
 }
 EXPORT_SYMBOL(fget);
 
 struct file *fget_raw(unsigned int fd)
 {
-	return __fget(fd, 0);
+	return __fget(fd, 0, 1);
 }
 EXPORT_SYMBOL(fget_raw);
 
@@ -753,7 +762,7 @@ static unsigned long __fget_light(unsigned int fd, fmode_t mask)
 			return 0;
 		return (unsigned long)file;
 	} else {
-		file = __fget(fd, mask);
+		file = __fget(fd, mask, 1);
 		if (!file)
 			return 0;
 		return FDPUT_FPUT | (unsigned long)file;