From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 78E9A352036 for ; Sat, 15 Aug 2026 06:11:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786774264; cv=none; b=ti5EJRqHN9oboTyWuuYKyHDrLUT/17krtip89AI249EEzR6CCXlfr3GdwSgHOQIOtJH++RsNHJl7U8pNtpgr4r8aiPfcEToXTnD3Dddbh2JCJL8UXyS6aaGmFhRSddSVUJh93bsj9UkbjHZKWnDG0DisThHCX5JXvDv143fF1Pk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786774264; c=relaxed/simple; bh=b6ZelEB0OwtxdBuyujfJKuhRaKDt1zFZcTAK6Ur7j3M=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=nHCzr70DJuGziWiEKHwOmXcn3pIOO5eWPT5yBOkRl0ZY1SkCx6cXCzH+Y+Q6xSpyll0vQhB8iudtAD+lxF4yMW0d60wEZNE8dL6iPLJ30E00FeoIZ9hyuBoUwBTv4L8ZkDyVSypy7grtI2slJBGDT737c8MejC1nu/OITqjWHHE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=uSwa3DJI; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="uSwa3DJI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 08DF11F000E9; Sat, 15 Aug 2026 06:11:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786774263; bh=KJEtslTLXcK90rUTcPyWi1pYgGRex2iHJV01hDGU8iM=; h=From:To:Cc:Subject:Date:Reply-To; b=uSwa3DJIUHTzrOsINM16chTezrJsnSWrbCqMV8VOkL2/xx5cXDESy9j/WnBOyoivr nF7eqHNrp8UqFdwjVA5Q914kYwIn0AWA579+tQboORHLD0TPADdLhy4A5gLMASW6Ny /xQJ9QJi/m/9QhNmud8BTVIT1Hq02sfdtNmCQ+DI= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-72095: dma-fence: Make dma_fence_dedup_array() robust against 0-count input Date: Sat, 15 Aug 2026 15:02:54 +0900 Message-ID: <2026081523-CVE-2026-72095-0ad7@gregkh> X-Mailer: git-send-email 2.55.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2713; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=1CfSC2GjY00Wxlg5h9XWQ6jraIghkZ2sFuw4r+vkIBc=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkNDJvZLuztkPFsf/76qNELtsffH9xV0y9IubTwwIrX+ jVdjTUpHbEsDIJMDLJiiixftvEc3V9xSNHL0PY0zBxWJpAhDFycAjARgZsMs9m94nx37b4o3xqT 4Px1/44nW0Pd+xnmKS//GFgYytxxTdd2wg7ul7/2qZ12AgA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: dma-fence: Make dma_fence_dedup_array() robust against 0-count input dma_fence_dedup_array() returns 1 when called with num_fences == 0: the for-loop body never executes, j stays at 0, and the final `return ++j` yields 1. This contradicts both the kernel-doc ("Return: Number of unique fences remaining in the array") and the natural expectation that 0 input gives 0 output. The caller __dma_fence_unwrap_merge() bails out via the `if (count == 0 || count == 1)` fast path and so is save. But amdgpu_userq_wait_*() could reach the dedup call with a zero local count and dereference an uninitialized fence slot in the array. Make the contract match the documentation by returning 0 early. This also skips an unnecessary sort() call on an empty array. The Linux kernel CVE team has assigned CVE-2026-72095 to this issue. Affected and fixed versions =========================== Issue introduced in 6.16 with commit 575ec9b0c2f11f40535ea737ed5a64792780d1ef and fixed in 6.18.40 with commit 7aa8f3dba53422465dbe1be8dbb7240304462bb2 Issue introduced in 6.16 with commit 575ec9b0c2f11f40535ea737ed5a64792780d1ef and fixed in 7.1.5 with commit e2d9a2ea178a5da0b4a6693e8ebca5c7fc4d7051 Issue introduced in 6.16 with commit 575ec9b0c2f11f40535ea737ed5a64792780d1ef and fixed in 7.2-rc2 with commit 77a9298741f8f9e8b963c977f5582ab21c6d3427 Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-72095 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: drivers/dma-buf/dma-fence-unwrap.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/7aa8f3dba53422465dbe1be8dbb7240304462bb2 https://git.kernel.org/stable/c/e2d9a2ea178a5da0b4a6693e8ebca5c7fc4d7051 https://git.kernel.org/stable/c/77a9298741f8f9e8b963c977f5582ab21c6d3427