From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 D9D057F9 for ; Sat, 11 Jan 2025 14:31:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736605907; cv=none; b=a3S1FccvGxTMw449xWMznICKxadi9COlOtc10/t66Uz/zEP6h1XHqs7fsmvjPXsYPipjq7TZxCXW6bch8VXe4d8Dy4jFfTkcN+vgae/pNTTRL1VjCq2Y7RiT2kACXJ3uTCUQpaRJJ3jO3Cm1IHBJGV/POTi068WXTyX3wc04b34= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736605907; c=relaxed/simple; bh=Zr7LbgvbrrH7uEL7kKL5Fw8isOFGt/HiJZgzevckb50=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Rp6nfBOE7aDDU0PHWbakETu62D6q1LV2QhuuYE7KG65GB7T3Adb7Yap2UIYypeHHYjeSjRO+O05WESfjXK+bFOKPIwLBpqNlQ/VAXlG0HfFYxDg39cE1233OlveEnSMTYtJyr0Aliqq77OOeBc8+bzch62ZDb3KfDz/9Sd+frRc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Uto3/1Pu; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Uto3/1Pu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 422D7C4CED2; Sat, 11 Jan 2025 14:31:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1736605907; bh=Zr7LbgvbrrH7uEL7kKL5Fw8isOFGt/HiJZgzevckb50=; h=From:To:Cc:Subject:Date:Reply-to:From; b=Uto3/1PuUt7zfao0vCoeGGlG3UEhTpN92dJ30ZhvRJqes4veNmPDI4yngQQW0NbJ1 gX+2ZTMPteq+/rLUv+BEEHwowhibQi5aCQrNw99I/eb7+3RS1PRBp9HRBmT6mSDzTT d7xmxDF5ZXbJljUfbo32oHIDwYkNvgA2YjzDukqU= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2025-23127: arm64: ptrace: fix partial SETREGSET for NT_ARM_FPMR Date: Sat, 11 Jan 2025 15:31:10 +0100 Message-ID: <2025011105-CVE-2025-23127-2b8d@gregkh> X-Mailer: git-send-email 2.48.0 Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Reply-to: , X-Developer-Signature: v=1; a=openpgp-sha256; l=3430; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=Zr7LbgvbrrH7uEL7kKL5Fw8isOFGt/HiJZgzevckb50=; b=owGbwMvMwCRo6H6F97bub03G02pJDOlNDau2T+WWuyex9ufpj90dMl+zo5f+iN7HvmVf3gQXs w7Z8CtHOmJZGASZGGTFFFm+bOM5ur/ikKKXoe1pmDmsTCBDGLg4BWAi2zIY5grmfQ7/dKr9rvzT 77qrgssSznx9xcUwh//mwev8Mf3X3i3Nt53y9MxmZp3GKAA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit Description =========== In the Linux kernel, the following vulnerability has been resolved: arm64: ptrace: fix partial SETREGSET for NT_ARM_FPMR Currently fpmr_set() doesn't initialize the temporary 'fpmr' variable, and a SETREGSET call with a length of zero will leave this uninitialized. Consequently an arbitrary value will be written back to target->thread.uw.fpmr, potentially leaking up to 64 bits of memory from the kernel stack. The read is limited to a specific slot on the stack, and the issue does not provide a write mechanism. Fix this by initializing the temporary value before copying the regset from userspace, as for other regsets (e.g. NT_PRSTATUS, NT_PRFPREG, NT_ARM_SYSTEM_CALL). In the case of a zero-length write, the existing contents of FPMR will be retained. Before this patch: | # ./fpmr-test | Attempting to write NT_ARM_FPMR::fpmr = 0x900d900d900d900d | SETREGSET(nt=0x40e, len=8) wrote 8 bytes | | Attempting to read NT_ARM_FPMR::fpmr | GETREGSET(nt=0x40e, len=8) read 8 bytes | Read NT_ARM_FPMR::fpmr = 0x900d900d900d900d | | Attempting to write NT_ARM_FPMR (zero length) | SETREGSET(nt=0x40e, len=0) wrote 0 bytes | | Attempting to read NT_ARM_FPMR::fpmr | GETREGSET(nt=0x40e, len=8) read 8 bytes | Read NT_ARM_FPMR::fpmr = 0xffff800083963d50 After this patch: | # ./fpmr-test | Attempting to write NT_ARM_FPMR::fpmr = 0x900d900d900d900d | SETREGSET(nt=0x40e, len=8) wrote 8 bytes | | Attempting to read NT_ARM_FPMR::fpmr | GETREGSET(nt=0x40e, len=8) read 8 bytes | Read NT_ARM_FPMR::fpmr = 0x900d900d900d900d | | Attempting to write NT_ARM_FPMR (zero length) | SETREGSET(nt=0x40e, len=0) wrote 0 bytes | | Attempting to read NT_ARM_FPMR::fpmr | GETREGSET(nt=0x40e, len=8) read 8 bytes | Read NT_ARM_FPMR::fpmr = 0x900d900d900d900d The Linux kernel CVE team has assigned CVE-2025-23127 to this issue. Affected and fixed versions =========================== Issue introduced in 6.9 with commit 4035c22ef7d43a6c00d6a6584c60e902b95b46af and fixed in 6.12.5 with commit 8ab73c34e3c5b580721696665eabd799346bc50b Issue introduced in 6.9 with commit 4035c22ef7d43a6c00d6a6584c60e902b95b46af and fixed in 6.13-rc2 with commit f5d71291841aecfe5d8435da2dfa7f58ccd18bc8 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-2025-23127 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/arm64/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/8ab73c34e3c5b580721696665eabd799346bc50b https://git.kernel.org/stable/c/f5d71291841aecfe5d8435da2dfa7f58ccd18bc8