[PATCH AUTOSEL 4.14 21/60] usb: gadget: Zero ffs_io_data

From: Sasha Levin
Date: Fri Jul 19 2019 - 00:21:46 EST


From: Andrzej Pietrasiewicz <andrzej.p@xxxxxxxxxxxxx>

[ 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@xxxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 79900c0b4f3a..cdffbe999500 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -1102,11 +1102,12 @@ 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;
}

@@ -1138,11 +1139,12 @@ 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