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[82.69.66.36]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4924923392dsm735988005e9.2.2026.06.24.07.52.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 24 Jun 2026 07:52:54 -0700 (PDT) From: David Laight To: Mikulas Patocka , Tony Asleson , "Bryn M . Reeves" , Alasdair Kergon , Mike Snitzer , Benjamin Marzinski , dm-devel@lists.linux.dev, linux-kernel@vger.kernel.org Cc: David Laight Subject: [PATCH 0/3] dm: simplify list ioctls Date: Wed, 24 Jun 2026 15:52:40 +0100 Message-Id: <20260624145243.2736-1-david.laight.linux@gmail.com> X-Mailer: git-send-email 2.39.5 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Scanning for poossibly unbounded strlen() found the device/disk manager ioctls that do a double scan of the data to check whether the caller supplied buffer is large enough, and then to fill it. If the buffer is too small the required size isn't returned. So simplify everything and make it all less likely to overrun the kernel buffer (copied back to user later) if anything changes between the scans. I managed a minimal test that the ioctls still work. David Laight (3): dm: __list_versions(): Only process targets once dm: list_devices(): Only process devices once dm: lookup_ioctl(): Use designated array initialers drivers/md/dm-ioctl.c | 207 +++++++++++++++++++----------------------- 1 file changed, 92 insertions(+), 115 deletions(-) -- 2.39.5