[PATCH 4.19 16/78] usb: gadget: Potential NULL dereference on allocation error

From: Greg Kroah-Hartman
Date: Mon Mar 04 2019 - 03:30:46 EST


4.19-stable review patch. If anyone has any objections, please let me know.

------------------

[ Upstream commit df28169e1538e4a8bcd8b779b043e5aa6524545c ]

The source_sink_alloc_func() function is supposed to return error
pointers on error. The function is called from usb_get_function() which
doesn't check for NULL returns so it would result in an Oops.

Of course, in the current kernel, small allocations always succeed so
this doesn't affect runtime.

Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/usb/gadget/function/f_sourcesink.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/function/f_sourcesink.c b/drivers/usb/gadget/function/f_sourcesink.c
index 9cdef108fb1b3..ed68a4860b7d8 100644
--- a/drivers/usb/gadget/function/f_sourcesink.c
+++ b/drivers/usb/gadget/function/f_sourcesink.c
@@ -838,7 +838,7 @@ static struct usb_function *source_sink_alloc_func(

ss = kzalloc(sizeof(*ss), GFP_KERNEL);
if (!ss)
- return NULL;
+ return ERR_PTR(-ENOMEM);

ss_opts = container_of(fi, struct f_ss_opts, func_inst);

--
2.19.1