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Sat, 08 Aug 2026 09:07:48 -0700 (PDT) From: Jeffin Philip To: gregkh@linuxfoundation.org Cc: i@zenithal.me, jeffinphilip14@gmail.com, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, shuah@kernel.org, stable@vger.kernel.org, syzbot+af76b01c9a0f0ab60fb0@syzkaller.appspotmail.com, valentina.manea.m@gmail.com Subject: [PATCH v2] usbip: usbip_host: fix null pointer dereference in Date: Sat, 8 Aug 2026 21:37:31 +0530 Message-ID: <20260808160731.8698-1-jeffinphilip14@gmail.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <2026080737-drank-trodden-16e4@gregkh> References: <2026080737-drank-trodden-16e4@gregkh> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Fri, Aug 07, 2026 at 03:09:56PM +0200, Greg KH wrote: >If you do not hold a lock when testing and doing something based on a >field, it will race and is broken. > >Again, step back and try to determine what you are trying to fix here, >and how that can be done in a race-free way. If you don't know, that's >fine too, I sure don't! :) I read the whole driver, and udev does not seem to be nulled anywhere except in stub_probe(), where it is only assigned. So, we can safely check for null udev alone. The driver itself seems to hold itself together as currently I don't see a potential race. probe() also cannot run as we set our status to STUB_BUSID_OTHER under lock so probe would ignore that too. Am I missing something else here that could create a potential race? Please advise. Thanks, Jeffin.