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 84A81352019; Thu, 20 Aug 2026 15:02:37 +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=1787238158; cv=none; b=nzfCvNv5tRCUwyyGgQRWbv7amyDOSkEKLahNLVanU2nqPWgQNWHh5cbcAmAz5Sjl+CTAE/sk2QVs4CmWTlP7DQFlUxt73heeR9A2g4zj3uZFS8CzbXyL3t6G8QQlPerokFh4oB4fe2vZ+3XaDZaFalU3WuorEnID9O0N+AGL5kE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787238158; c=relaxed/simple; bh=Us6CXxAMnPKnO+e+LiOoRx5AbhllN6YVON/jwrv0lQs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JY8alXrQcLtYsHnsNFEP6bhG7NPyyy6V0vpPA3wxI+CpKu9FU18DQnhnQyRwfZFXDH15A2cJfutSJmqswEE6E/XY8mixJfrbQWj+kiLA1XojFLpRmmr///yajaH/sFkhM0qfXmijy6hx0ddj/+ngU/OFxRQNjjh62EMCJ+d/J8c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=qD7kPO5H; 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="qD7kPO5H" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE13D1F000E9; Thu, 20 Aug 2026 15:02:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787238157; bh=OapKndssb0qd3RI2v7o0vvopxef/MgcBHaomZhojda0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=qD7kPO5HnojkObiiArFsLzQkh6OcKFSHbjmPOj6VV97R/CuZUjiwB7OB432Q86Z7C OdsHS2kgylzBYR7c2zq7ggnMnbEDurC32QLpZURWRVAqF1h7QyaDEKnBbYU2+YByGG kIPo7r3T5gvl/qS3YLvapfjnopAB1Ph2l0naoDMs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Nayna Jain , R Nageswara Sastry , George Wilson , Madhavan Srinivasan Subject: [PATCH 7.1 050/228] powerpc/pseries: lparcfg - fix kbuf[] underflow Date: Thu, 20 Aug 2026 16:53:12 +0200 Message-ID: <20260820145245.990018875@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260820145244.450574346@linuxfoundation.org> References: <20260820145244.450574346@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: George Wilson commit fb442a6673ff1046bf67754957d95880fdb394b5 upstream. In lparcfg_write(), a count of 0 results in kbuf[] being indexed at -1. Check for count == 0 in the existing check for count > sizeof(kbuf) and return -EINVAL if true. Fixes: 74422e2b1939 ("powerpc/pseries: Remove VLA from lparcfg_write()") Acked-by: Nayna Jain Tested-by: R Nageswara Sastry Cc: stable@vger.kernel.org # 4.20 Signed-off-by: George Wilson Signed-off-by: Madhavan Srinivasan Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/platforms/pseries/lparcfg.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/powerpc/platforms/pseries/lparcfg.c +++ b/arch/powerpc/platforms/pseries/lparcfg.c @@ -697,7 +697,7 @@ static ssize_t lparcfg_write(struct file if (!firmware_has_feature(FW_FEATURE_SPLPAR)) return -EINVAL; - if (count > sizeof(kbuf)) + if (count == 0 || count > sizeof(kbuf)) return -EINVAL; if (copy_from_user(kbuf, buf, count))