| Message ID | 20240923202019.37875-1-m.arhipov@rosa.ru (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] usb: gadget: r8a66597-udc: Fix double free in r8a66597_probe | expand |
On 2024-09-23 23:20:19 [+0300], Mikhail Arkhipov wrote: > The function r8a66597_free_request is already called in the err_add_udc > block, and freeing r8a66597->ep0_req twice may lead to a double free error. > > If the probe process fails and the r8a66597_probe function subsequently > goes through its error handling path. Since r8a66597_free_request is called > multiple times in different error handling sections, it leads to an attempt > to free the same memory twice. > > Remove the redundant call to r8a66597_free_request in the clean_up2 block. > > Found by Linux Verification Center (linuxtesting.org) with SVACE. > > Fixes: 0f91349b89f3 ("usb: gadget: convert all users to the new udc infrastructure") > Signed-off-by: Mikhail Arkhipov <m.arhipov@rosa.ru> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Sebastian
diff --git a/drivers/usb/gadget/udc/r8a66597-udc.c b/drivers/usb/gadget/udc/r8a66597-udc.c index db4a10a979f9..a9b82f371abb 100644 --- a/drivers/usb/gadget/udc/r8a66597-udc.c +++ b/drivers/usb/gadget/udc/r8a66597-udc.c @@ -1956,9 +1956,6 @@ static int r8a66597_probe(struct platform_device *pdev) if (r8a66597->pdata->on_chip) clk_disable_unprepare(r8a66597->clk); - if (r8a66597->ep0_req) - r8a66597_free_request(&r8a66597->ep[0].ep, r8a66597->ep0_req); - return ret; }
The function r8a66597_free_request is already called in the err_add_udc block, and freeing r8a66597->ep0_req twice may lead to a double free error. If the probe process fails and the r8a66597_probe function subsequently goes through its error handling path. Since r8a66597_free_request is called multiple times in different error handling sections, it leads to an attempt to free the same memory twice. Remove the redundant call to r8a66597_free_request in the clean_up2 block. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 0f91349b89f3 ("usb: gadget: convert all users to the new udc infrastructure") Signed-off-by: Mikhail Arkhipov <m.arhipov@rosa.ru> --- v2: Remove redundant call to r8a66597_free_request in clean_up2 block instead of assigning r8a66597->ep0_req to NULL, as suggested by Sebastian Andrzej Siewior <bigeasy@linutronix.de>. drivers/usb/gadget/udc/r8a66597-udc.c | 3 --- 1 file changed, 3 deletions(-)