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 859523A7820 for ; Sun, 19 Jul 2026 15:43:04 +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=1784475785; cv=none; b=Pc+3m9f330zidq5s/GNB6D7I8Im/mld5focmuOs++TIck0deQblne1SMrqfY7Y+pSLFjq6Y+6B8KoEm+bxxVYEzrV18CGkp9whPrg/NXw8sUkUr7bZ4PX+fo8I3ZTw77p14MlFTumawN18oZSqVYuu8YrIwuwDZiqEQxQcCY4H4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784475785; c=relaxed/simple; bh=77OUZNjj+iM2F51V4tGSMa2t/8lJ26+o8/NS64Y62nQ=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=U0dLtiMBl1s33rvSb/FS2WB0UZ3nTNlVb0dkFOKsRLPZSH0RTs4Ti33EGa67IU10Crg2w/MLC/I8RERyMWUyemhPbmYTh0Znzf2Gph9gyoqhYSxaJUL/oUMK4Fg47S88vGEgpcMti4Xbq+NdOpOAEIvgEaIaAr7e2ck5g4yEIks= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=K6xj7I97; 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="K6xj7I97" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE4E71F000E9; Sun, 19 Jul 2026 15:43:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784475784; bh=Pbjhc3UwVk5KnxGqJ/GY/+b5Ciow98dROK7wJaaIii4=; h=From:To:Cc:Subject:Date:Reply-To; b=K6xj7I97ipA0UkLuqbX4IF6Xm0OHqbW2l4f23Qa4h+NxMdyqcCZANrvn9GHD9Djjh lIVBOhMxkN7VdG0+865J89rFwcz/XQy8ZFFCs/0s5ykkaZsZhOgszXwP5fzrf4Xpxx vXVdYA2UrqrqD7Ql9a61putbR7J5oryfo6B/7rIk= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-64082: riscv: Fix register corruption from uninitialized cregs on error Date: Sun, 19 Jul 2026 17:39:04 +0200 Message-ID: <2026071915-CVE-2026-64082-bf76@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=2391; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=7o+lWRgzvU/4dY2zBMRkdpdYdqBqN4ucb3OxN8rRkCg=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkx79PXFbaL3791bP22EzMr9x+8aaXT6nn5Rn12elANv wz7+2nFHbEsDIJMDLJiiixftvEc3V9xSNHL0PY0zBxWJpAhDFycAjAR73MMCzq28P50M/5+dfn1 4P2Pd955FvLNdjXDfN9LrotZs86eMBJ9+TDS4M29LbxLWAE= 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: riscv: Fix register corruption from uninitialized cregs on error compat_riscv_gpr_set() calls cregs_to_regs() unconditionally, even when user_regset_copyin() fails. Since cregs is an uninitialized stack variable, a copyin failure causes uninitialized stack data to be written into the target task's pt_regs, corrupting its register state and potentially leaking kernel stack contents. compat_restore_sigcontext() has the same issue: it calls cregs_to_regs() even when __copy_from_user() fails, leading to the same corruption of the signal-returning task's register state on error. Only call cregs_to_regs() when the user copy succeeds. The Linux kernel CVE team has assigned CVE-2026-64082 to this issue. Affected and fixed versions =========================== Issue introduced in 5.19 with commit 7383ee05314be58f8f9f018ee0ac53bef3808aea and fixed in 7.0.11 with commit 9e020156833f1ad0d425a1e3d85b65639f1c1c50 Issue introduced in 5.19 with commit 7383ee05314be58f8f9f018ee0ac53bef3808aea and fixed in 7.1 with commit 6ebcbb53fc9bc30843054ed99fd60b8e542628f4 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-2026-64082 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: arch/riscv/kernel/compat_signal.c arch/riscv/kernel/ptrace.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/9e020156833f1ad0d425a1e3d85b65639f1c1c50 https://git.kernel.org/stable/c/6ebcbb53fc9bc30843054ed99fd60b8e542628f4