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 7B289213E7D for ; Fri, 28 Mar 2025 11:51:39 +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=1743162699; cv=none; b=G/yygmUG9vOugX34ECjyhP/UeDdmlyL1gWhu/SnBjXSU39+xYPYUdt3TQEpOWBHIPMkKC+c+KXwyon08koh8+AGUMR4xHzpRMyAR4GBH6Q2tBFUT8rVuP+AR8EZnM/hNS6dpvYlLWuwkjz9DH3IubLkHjv3EgOlTwGGP6iy4KTs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743162699; c=relaxed/simple; bh=MVH5EuCt00aXD/uHtRbXKmk5SpPnle7FziGF2MoENTs=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=EpAZbIPpyQBOw2Obepf6NQU+Is3EjIQbHUWF6xdUjLYH/v2yZdBQIVpkWfD8zD2okAKVdvyAzaAVyxj7bEWD7LgMfYPcqncC4fUw72M/9gbiXGk2TzC+NgIY5fvi70COW6RtIMqxQqxG291iig/6iw1gctVDlHzAlWzua2MBaOU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=NtpikPw6; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="NtpikPw6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7E5BFC4CEE4; Fri, 28 Mar 2025 11:51:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743162698; bh=MVH5EuCt00aXD/uHtRbXKmk5SpPnle7FziGF2MoENTs=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=NtpikPw6W3SVPGsBrEvfqwRQoMM5k8Cv0Ug9ME0/6sxdJvPUmAfyxDU2Wpz5Lcbke IJIR3QhNy26Cwh+O6YYEP1TQQS7PL6vHXcpmLQB3+UzVXLo5SaXfWa8YK3Mxm61IWl 634NyApAPO2aKUE5L/QLEpZpK+d/KFDFr/xTJ0U7mxPx3AQOxTAu1jPZkNC3SuCYZG bCyZJPeZ2kHmtsC8KHthDuHuhXounvxIkYMx+/TDORxtyREew/nsNz1pAOLE42Ypva MIlWM2VP8XEmP4syFtnRmR7G8MHSLfjaGIpUa7H5u5aOF7G1fnkNeKDZfCPyQuvY78 UxfJhmx0fyyjA== Date: Fri, 28 Mar 2025 04:51:37 -0700 From: Jakub Kicinski To: Taehee Yoo Cc: davem@davemloft.net, pabeni@redhat.com, edumazet@google.com, andrew+netdev@lunn.ch, horms@kernel.org, netdev@vger.kernel.org, jdamato@fastly.com, sdf@fomichev.me, almasrymina@google.com, xuanzhuo@linux.alibaba.com Subject: Re: [PATCH net] net: fix use-after-free in the netdev_nl_sock_priv_destroy() Message-ID: <20250328045137.0730fc6c@kernel.org> In-Reply-To: <20250328062237.3746875-1-ap420073@gmail.com> References: <20250328062237.3746875-1-ap420073@gmail.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Fri, 28 Mar 2025 06:22:37 +0000 Taehee Yoo wrote: > In the netdev_nl_sock_priv_destroy(), an instance lock is acquired > before calling net_devmem_unbind_dmabuf(), then releasing an instance > lock(netdev_unlock(binding->dev)). > However, a binding is freed in the net_devmem_unbind_dmabuf(). > So using a binding after net_devmem_unbind_dmabuf() occurs UAF. > To fix this UAF, it needs to use temporary variable. > > Fixes: ba6f418fbf64 ("net: bubble up taking netdev instance lock to callers of net_devmem_unbind_dmabuf()") > Signed-off-by: Taehee Yoo Reviewed-by: Jakub Kicinski Thanks!