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Subject[PATCH] usb: musb: Fix a possible null-pointer dereference in musb_handle_intr_connect()
Date
In musb_handle_intr_connect(), there is an if statement on line 783 to
check whether musb->hcd is NULL:
if (musb->hcd)

When musb->hcd is NULL, it is used on line 797:
musb_host_poke_root_hub(musb);
if (musb->hcd->status_urb)

Thus, a possible null-pointer dereference may occur.

To fix this bug, musb->hcd is checked before calling
musb_host_poke_root_hub().

This bug is found by a static analysis tool STCheck written by us.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
---
drivers/usb/musb/musb_core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index 9f5a4819a744..329ff52f8167 100644
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -794,7 +794,8 @@ static void musb_handle_intr_connect(struct musb *musb, u8 devctl, u8 int_usb)
break;
}

- musb_host_poke_root_hub(musb);
+ if (musb->hcd)
+ musb_host_poke_root_hub(musb);

musb_dbg(musb, "CONNECT (%s) devctl %02x",
usb_otg_state_string(musb->xceiv->otg->state), devctl);
--
2.17.0
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