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 170F3CA40; Tue, 16 Jul 2024 15:37:37 +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=1721144257; cv=none; b=GwtRHROe68dAWA7wHz/Y9LnUkPKUDc76bac0/j0lN76dZkN7PXtv+7xfBfCs3IXzuQjC0k1r0ro98BpfXRg1GJNmgNsrmrm9NZ0l98bQ7XujKMyxMSEJY+7iI8Kd/gI+BJWJUDWr49x65xqapTEaCImvCn+gufxdQ22HefPIaEQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721144257; c=relaxed/simple; bh=jBtWT8au1PqxjmrqZwXOwLhL5SVDqGtX+YX7L1rSRb4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sX6kdbboMAU2cJ4mGaIy0NH8qpL2K5I3oMwBtMHGIUWQPP9hzsTlDFUoizO7vTqBGmukQxWUcMbTbmxwxNjpe75d/gsNAzA2+4bWsctTI0A/HB3bnc9pHOiZDeiiqnKeS4dzKar5axIoDfDLyd34pcaG/FMoCI3WBWHJk3+ow7E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Btu7DgyJ; 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="Btu7DgyJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 654A9C116B1; Tue, 16 Jul 2024 15:37:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1721144257; bh=jBtWT8au1PqxjmrqZwXOwLhL5SVDqGtX+YX7L1rSRb4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Btu7DgyJfnNWk4N8Ja9+krvdkJitlEvcJURZ0pu8HHr1DrP2sYx0gB3VRKgFJZuaz gPgsmtYFxslSFmFWgvmZhrnhR5/9cUV14NwQcdNJiast3K8ICNk1JJZ2XPB8DoW+ef ADnzTwDcJQvjrtOXOwQot48hL6bsC0D1VC/Tqxpo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Andrew Lunn , Simon Horman , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.4 12/78] net: dsa: mv88e6xxx: Correct check for empty list Date: Tue, 16 Jul 2024 17:30:44 +0200 Message-ID: <20240716152741.100860813@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240716152740.626160410@linuxfoundation.org> References: <20240716152740.626160410@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Simon Horman [ Upstream commit 4c7f3950a9fd53a62b156c0fe7c3a2c43b0ba19b ] Since commit a3c53be55c95 ("net: dsa: mv88e6xxx: Support multiple MDIO busses") mv88e6xxx_default_mdio_bus() has checked that the return value of list_first_entry() is non-NULL. This appears to be intended to guard against the list chip->mdios being empty. However, it is not the correct check as the implementation of list_first_entry is not designed to return NULL for empty lists. Instead, use list_first_entry_or_null() which does return NULL if the list is empty. Flagged by Smatch. Compile tested only. Reviewed-by: Andrew Lunn Signed-off-by: Simon Horman Link: https://lore.kernel.org/r/20240430-mv88e6xx-list_empty-v3-1-c35c69d88d2e@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/dsa/mv88e6xxx/chip.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c index 81e6227cc8758..cf3d574374376 100644 --- a/drivers/net/dsa/mv88e6xxx/chip.c +++ b/drivers/net/dsa/mv88e6xxx/chip.c @@ -115,8 +115,8 @@ struct mii_bus *mv88e6xxx_default_mdio_bus(struct mv88e6xxx_chip *chip) { struct mv88e6xxx_mdio_bus *mdio_bus; - mdio_bus = list_first_entry(&chip->mdios, struct mv88e6xxx_mdio_bus, - list); + mdio_bus = list_first_entry_or_null(&chip->mdios, + struct mv88e6xxx_mdio_bus, list); if (!mdio_bus) return NULL; -- 2.43.0