[PATCH 4.4 118/158] usb: gadget: Zero ffs_io_data

Greg Kroah-Hartman
2019-08-02T09:34:40Z

[ Upstream commit 508595515f4bcfe36246e4a565cf280937aeaade ]

In some cases the "Allocate & copy" block in ffs_epfile_io() is not
executed. Consequently, in such a case ffs_alloc_buffer() is never called
and struct ffs_io_data is not initialized properly. This in turn leads to
problems when ffs_free_buffer() is called at the end of ffs_epfile_io().

This patch uses kzalloc() instead of kmalloc() in the aio case and memset()
in non-aio case to properly initialize struct ffs_io_data.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/usb/gadget/function/f_fs.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 4800bb22cdd6..4cb1355271ec 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -912,11 +912,12 @@ static ssize_t ffs_epfile_write_iter(struct kiocb *kiocb, struct iov_iter *from)
ENTER();

if (!is_sync_kiocb(kiocb)) {
- p = kmalloc(sizeof(io_data), GFP_KERNEL);
+ p = kzalloc(sizeof(io_data), GFP_KERNEL);
if (unlikely(!p))
return -ENOMEM;
p->aio = true;
} else {
+ memset(p, 0, sizeof(*p));
p->aio = false;
}

@@ -948,11 +949,12 @@ static ssize_t ffs_epfile_read_iter(struct kiocb *kiocb, struct iov_iter *to)
ENTER();

if (!is_sync_kiocb(kiocb)) {
- p = kmalloc(sizeof(io_data), GFP_KERNEL);
+ p = kzalloc(sizeof(io_data), GFP_KERNEL);
if (unlikely(!p))
return -ENOMEM;
p->aio = true;
} else {
+ memset(p, 0, sizeof(*p));
p->aio = false;
}

--
2.20.1