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Thu, 11 Jun 2026 03:28:52 -0700 (PDT) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20260408-wip-cuse-leak-fix-v1-0-1c028d575e97@redhat.com> In-Reply-To: <20260408-wip-cuse-leak-fix-v1-0-1c028d575e97@redhat.com> From: Miklos Szeredi Date: Thu, 11 Jun 2026 12:28:41 +0200 X-Gm-Features: AVVi8CfnSu0q8VDbJtoyGEYJCcOjl2tDogUfywRgVL7x8ZxksWLzTZXyfJZDryE Message-ID: Subject: Re: [PATCH 0/2] fuse: fix CUSE device node leak and add regression test To: aruiz@redhat.com Cc: Shuah Khan , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Content-Type: text/plain; charset="UTF-8" On Wed, 8 Apr 2026 at 17:23, Alberto Ruiz via B4 Relay wrote: > Patch 2 adds a kselftest that reproduces the bug by forcing cdev_alloc() > to fail after device_add() has succeeded, then verifying that no /dev > node is leaked. To trigger the failure deterministically, a > CONFIG_FAULT_INJECTION-guarded module parameter (cuse_inject_cdev_failure) > is added to cuse.c. The test falls back to failslab with stack-trace > filtering when the parameter is unavailable. > > I'm on the fence about the fault injection parameter in patch 2 -- it's > only a few lines and it's guarded behind CONFIG_FAULT_INJECTION, but I > understand if it feels too intrusive for production code. Happy to drop > the kselftest or rework the injection approach if the maintainers prefer. > The fix in patch 1 stands on its own regardless. I don't think it's worth adding this to upstream, though I'm impressed by the thoroughness of your work. I'll reference this patchset from commit header so the information is retained. Thanks, Miklos