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 B894E48786; Sat, 3 Feb 2024 04:15:33 +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=1706933733; cv=none; b=MIg45G0eyaDD5AT9Va8ZHZCn19ViOQnGpo4YQkn5uzgb+btdxXoVl2aOXmJmFr64T6psCFjzt1CMlxaROkeI3QuMhg+i/WmF2E9E2DMtz8zpcZEG+H7/SiQCr4hMkrjhcpV6Zhd9bfjPnEnrJdrBS+oLZ5XTLkfRKQSFruVOSvw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706933733; c=relaxed/simple; bh=RjD9MTeZdwid756Ahi882o8sfCdm7zKjVdYpKGgdnVw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=SnZcAnaFjQtk05pWdPPCYCGPsE2qKONAX5yU62hQ8a2uHySWbWir0FNOlB+1Vhjxlx72UMf06HcD5izpGZlsIAt7TTrdPW5cKJxdRKEJPIXPBLancNro5GN6BFALssg0w5npoxv05Rx5RQPXINgTT33ylZFPkbfS336Ofhtbe4U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=dcwIZHb4; 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="dcwIZHb4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 80132C433F1; Sat, 3 Feb 2024 04:15:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1706933733; bh=RjD9MTeZdwid756Ahi882o8sfCdm7zKjVdYpKGgdnVw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dcwIZHb4PE1TWnz9wuy+tqXohfk/nLfrU2c06NbDmQb358tCIXjUDWUDgH4sb38y7 XQNrc5Gr763UKcyZ/PFOYtneT9VRYVh39z5gqB1Gpg2OAQ4dWVGgtpoMDAUe1ncMc2 a2fPPs42rxWhK5WN16I/B92yOJHFsyE1tK9Phe8I= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Prarit Bhargava , "Rafael J. Wysocki" , Sasha Levin Subject: [PATCH 6.7 021/353] ACPI: extlog: fix NULL pointer dereference check Date: Fri, 2 Feb 2024 20:02:19 -0800 Message-ID: <20240203035404.413037823@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240203035403.657508530@linuxfoundation.org> References: <20240203035403.657508530@linuxfoundation.org> User-Agent: quilt/0.67 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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: Prarit Bhargava [ Upstream commit 72d9b9747e78979510e9aafdd32eb99c7aa30dd1 ] The gcc plugin -fanalyzer [1] tries to detect various patterns of incorrect behaviour. The tool reports: drivers/acpi/acpi_extlog.c: In function ‘extlog_exit’: drivers/acpi/acpi_extlog.c:307:12: warning: check of ‘extlog_l1_addr’ for NULL after already dereferencing it [-Wanalyzer-deref-before-check] | | 306 | ((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN; | | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~ | | | | | (1) pointer ‘extlog_l1_addr’ is dereferenced here | 307 | if (extlog_l1_addr) | | ~ | | | | | (2) pointer ‘extlog_l1_addr’ is checked for NULL here but it was already dereferenced at (1) | Fix the NULL pointer dereference check in extlog_exit(). Link: https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Static-Analyzer-Options.html # [1] Signed-off-by: Prarit Bhargava Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- drivers/acpi/acpi_extlog.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/acpi_extlog.c b/drivers/acpi/acpi_extlog.c index 71e8d4e7a36c..ca87a0939135 100644 --- a/drivers/acpi/acpi_extlog.c +++ b/drivers/acpi/acpi_extlog.c @@ -308,9 +308,10 @@ static int __init extlog_init(void) static void __exit extlog_exit(void) { mce_unregister_decode_chain(&extlog_mce_dec); - ((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN; - if (extlog_l1_addr) + if (extlog_l1_addr) { + ((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN; acpi_os_unmap_iomem(extlog_l1_addr, l1_size); + } if (elog_addr) acpi_os_unmap_iomem(elog_addr, elog_size); release_mem_region(elog_base, elog_size); -- 2.43.0