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client-ip=165.204.84.17; helo=satlexmb07.amd.com; pr=C Received: from satlexmb07.amd.com (165.204.84.17) by BY1PEPF0001AE1B.mail.protection.outlook.com (10.167.242.103) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.360.3 via Frontend Transport; Sat, 22 Aug 2026 19:22:15 +0000 Received: from [127.0.1.1] (10.180.168.240) by satlexmb07.amd.com (10.181.42.216) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.45; Sat, 22 Aug 2026 14:22:12 -0500 From: Shivank Garg Subject: [PATCH v5 0/4] dmaengine: fix kref underflow and UAF in dma_chan_put() Date: Sat, 22 Aug 2026 19:22:02 +0000 Message-ID: <20260822-dmaengine-kref-fix-v5-0-d4a4ee47d927@amd.com> Precedence: bulk X-Mailing-List: dmaengine@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-B4-Tracking: v=1; b=H4sIANr2iWoC/33PTQ6CMBAF4KuYrh3TKf0BV97DuCjtFBsDGDAEQ 7i71Q2QEJdvJu+bzMR66iL17HyYWEdD7GPbpKCOB+butqkIok+ZCS40V5iDry01VWwIHh0FCHE EUwq0ruSFVIql4jMt4vhDr7eU77F/td37d2PA7/QvNyAgSK9RKC7zUJqLrf3JtTX7YoNYAULvA gI4ZD5oboN1HP0WyBYgx30gS4AhozE3KJUPW0Cugf0XZAKcplAUKLWwfAHmef4AGTeXBXUBAAA = X-Change-ID: 20260518-dmaengine-kref-fix-7b21acb09455 To: Vinod Koul , Frank Li , "Logan Gunthorpe" , Andrew Morton CC: , , , Shivank Garg , Frank Li , Sashiko X-Mailer: b4 0.15-dev-47d62 X-Developer-Signature: v=1; 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[1]: https://lore.kernel.org/dmaengine/20260605-sdxi-base-v3-0-4d38ca2bdffe@amd.com Signed-off-by: Shivank Garg --- Changes in v5: - Use int return type and add __must_check for dma_device_get() (Frank) - Drop the comment above synchronize_rcu() and note in the commit message that this will delay for grace period dma_list_mutex held (Logan) - Link to v4: https://lore.kernel.org/r/20260818-dmaengine-kref-fix-v4-0-c6ef991462a0@amd.com Changes in v4: - Add dma_device_get() helper (Frank) - Drop dma_chan_put() move change (Frank) - Link to v3: https://lore.kernel.org/r/20260816-dmaengine-kref-fix-v3-0-7e76187145df@amd.com Changes in v3: - Add patch 3: add synchronize_rcu() to wait for RCU readers to prevent use-after-free. (Sashiko) - Link to v2: https://lore.kernel.org/r/20260526-dmaengine-kref-fix-v2-0-3df60afac01d@amd.com Changes in v2: - Add patch 2 fixing the dma_chan_put()/dma_release_channel() use-after-free (sashiko) - Link to v1: https://lore.kernel.org/r/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com --- Shivank Garg (4): dmaengine: add dma_device_get() helper dmaengine: Fix device kref underflow in dma_chan_put() dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel() dmaengine: wait for RCU readers before releasing dma_device drivers/dma/dmaengine.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) --- base-commit: a4ff2be345d0abc943da8dd8da98151843b750dc change-id: 20260518-dmaengine-kref-fix-7b21acb09455 Best regards, -- Shivank Garg