[ Upstream commit 5d78e1c2b7f4be00bbe62141603a631dc7812f35 ]

syzbot found the following crash on:

general protection fault: 0000 [#1] SMP KASAN RIP: 0010:snd_usb_pipe_sanity_check+0x80/0x130 sound/usb/helper.c:75 Call Trace: snd_usb_motu_microbookii_communicate.constprop.0+0xa0/0x2fb sound/usb/quirks.c:1007 snd_usb_motu_microbookii_boot_quirk sound/usb/quirks.c:1051 [inline] snd_usb_apply_boot_quirk.cold+0x163/0x370 sound/usb/quirks.c:1280 usb_audio_probe+0x2ec/0x2010 sound/usb/card.c:576 usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361 really_probe+0x281/0x650 drivers/base/dd.c:548 ....

It was introduced in commit 801ebf1043ae for checking pipe and endpoint types. It is fixed by adding a check of the ep pointer in question.

BugLink: https://syzkaller.appspot.com/bug?extid=d59c4387bfb6eced94e2 Reported-by: syzbot syzbot+d59c4387bfb6eced94e2@syzkaller.appspotmail.com Fixes: 801ebf1043ae ("ALSA: usb-audio: Sanity checks for each pipe and EP types") Cc: Andrey Konovalov andreyknvl@google.com Signed-off-by: Hillf Danton hdanton@sina.com Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Dan Carpenter dan.carpenter@linaro.org --- sound/usb/helper.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/usb/helper.c b/sound/usb/helper.c index b1cc9499c57e..029489b490ca 100644 --- a/sound/usb/helper.c +++ b/sound/usb/helper.c @@ -85,7 +85,7 @@ int snd_usb_pipe_sanity_check(struct usb_device *dev, unsigned int pipe) struct usb_host_endpoint *ep;

ep = usb_pipe_endpoint(dev, pipe); - if (usb_pipetype(pipe) != pipetypes[usb_endpoint_type(&ep->desc)]) + if (!ep || usb_pipetype(pipe) != pipetypes[usb_endpoint_type(&ep->desc)]) return -EINVAL; return 0; }