2018-08-30 10:22:25

by Nicholas Mc Guire

[permalink] [raw]
Subject: [PATCH 1/2] usb: gadget: fsl_udc_core: check allocation return value and cleanup on failure

The allocation with fsl_alloc_request() and kmalloc() were unchecked
fixed this up with a NULL check and appropriate cleanup.

Additionally udc->ep_qh_size was reset to 0 on failure of allocation.
Similar udc->phy_mode is initially 0 (as udc_controller was
allocated with kzalloc in fsl_udc_probe()) so reset it to 0 as well
so that this function is side-effect free on failure. Not clear if
this is necessary or sensible as fsl_udc_release() probably can not
be called if fsl_udc_probe() failed - but it should not hurt.

Signed-off-by: Nicholas Mc Guire <[email protected]>
Fixes: b504882da5 ("USB: add Freescale high-speed USB SOC device controller driver")
---

Problem located with experimental coccinelle script

Patch was compile tested with: imx_v6_v7_defconfig (implies USB_FSL_USB2=y)
(with a large number of sparse warnings not related to the proposed change
and one smatch warning)

Patch is against 4.19-rc1 (localversion-next is next-20180830)

drivers/usb/gadget/udc/fsl_udc_core.c | 30 ++++++++++++++++++++++++++----
1 file changed, 26 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/gadget/udc/fsl_udc_core.c b/drivers/usb/gadget/udc/fsl_udc_core.c
index be59309..e637afb 100644
--- a/drivers/usb/gadget/udc/fsl_udc_core.c
+++ b/drivers/usb/gadget/udc/fsl_udc_core.c
@@ -2247,8 +2247,10 @@ static int struct_udc_setup(struct fsl_udc *udc,
udc->phy_mode = pdata->phy_mode;

udc->eps = kcalloc(udc->max_ep, sizeof(struct fsl_ep), GFP_KERNEL);
- if (!udc->eps)
- return -1;
+ if (!udc->eps) {
+ ERR("kmalloc udc endpoint status failed\n");
+ goto eps_alloc_failed;
+ }

/* initialized QHs, take care of alignment */
size = udc->max_ep * sizeof(struct ep_queue_head);
@@ -2262,8 +2264,7 @@ static int struct_udc_setup(struct fsl_udc *udc,
&udc->ep_qh_dma, GFP_KERNEL);
if (!udc->ep_qh) {
ERR("malloc QHs for udc failed\n");
- kfree(udc->eps);
- return -1;
+ goto ep_queue_alloc_failed;
}

udc->ep_qh_size = size;
@@ -2272,8 +2273,17 @@ static int struct_udc_setup(struct fsl_udc *udc,
/* FIXME: fsl_alloc_request() ignores ep argument */
udc->status_req = container_of(fsl_alloc_request(NULL, GFP_KERNEL),
struct fsl_req, req);
+ if (!udc->status_req) {
+ ERR("kzalloc for udc status request failed\n");
+ goto udc_status_alloc_failed;
+ }
+
/* allocate a small amount of memory to get valid address */
udc->status_req->req.buf = kmalloc(8, GFP_KERNEL);
+ if (!udc->status_req->req.buf) {
+ ERR("kzalloc for udc request buffer failed\n");
+ goto udc_req_buf_alloc_failed;
+ }

udc->resume_state = USB_STATE_NOTATTACHED;
udc->usb_state = USB_STATE_POWERED;
@@ -2281,6 +2291,18 @@ static int struct_udc_setup(struct fsl_udc *udc,
udc->remote_wakeup = 0; /* default to 0 on reset */

return 0;
+
+udc_req_buf_alloc_failed:
+ kfree(udc->status_req);
+udc_status_alloc_failed:
+ kfree(udc->ep_qh);
+ udc->ep_qh_size = 0;
+ep_queue_alloc_failed:
+ kfree(udc->eps);
+eps_alloc_failed:
+ udc->phy_mode = 0;
+ return -1;
+
}

/*----------------------------------------------------------------
--
2.1.4



2018-08-30 10:22:25

by Nicholas Mc Guire

[permalink] [raw]
Subject: [PATCH 2/2] usb: gadget: fsl_udc_core: fixup struct_udc_setup documentation

The original implementation from commit b504882da539
("USB: add Freescale high-speed USB SOC device controller driver")
returned NULL on failure and an allocated + initialized struct fsl_udc on
success. The current code introduced in commit 4365831dadfe
("USB: fsl_usb2_udc: Get max ep number from DCCPARAMS register") only
provides partial initialization as well as returning 0 on success and -1
on failures. The function documentation is updated accordingly.

Signed-off-by: Nicholas Mc Guire <[email protected]>
Fixes: 4365831dadfe ("USB: fsl_usb2_udc: Get max ep number from DCCPARAMS register")
---

Problem located during code-review

Patch is against 4.19-rc1 (localversion-next is next-20180830)

drivers/usb/gadget/udc/fsl_udc_core.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/udc/fsl_udc_core.c b/drivers/usb/gadget/udc/fsl_udc_core.c
index e637afb..680b46e 100644
--- a/drivers/usb/gadget/udc/fsl_udc_core.c
+++ b/drivers/usb/gadget/udc/fsl_udc_core.c
@@ -2234,8 +2234,10 @@ static void fsl_udc_release(struct device *dev)
Internal structure setup functions
*******************************************************************/
/*------------------------------------------------------------------
- * init resource for globle controller
- * Return the udc handle on success or NULL on failure
+ * init resource for global controller called by fsl_udc_probe()
+ * On success the udc handle is initialized, on failure it is
+ * unchanged (reset).
+ * Return 0 on success and -1 on allocation failure
------------------------------------------------------------------*/
static int struct_udc_setup(struct fsl_udc *udc,
struct platform_device *pdev)
--
2.1.4