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 1FF0C69D29; Sun, 26 May 2024 09:43:01 +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=1716716581; cv=none; b=tgzAM67/G0YybCQyvQ7CDOHWVpgu7sbSl0Gt2tLdVMEM7FzhlosVtdqW8iVrhZBobGfzzp24pwyQYbmlsCngcrCiejlLFN/HiWoNSa2PmKs2C+Gq3uSp5PmRUTPQbYzMOX+X+Js13w5Rf5MGhz6TuKLpR57eiboKDqZgwcE5q7I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716716581; c=relaxed/simple; bh=JgenaFV+7nFpbALnZO+VIAqY0wsCGJI94ujw+zT+hmw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=l/hcQF233Xo6lBFF5HkJG0CqFt3tQuGkurirWEEIb9T6z14t84YhlXG3dsNRzjZHM0wK7+ImBrL6jmOZWiAo1Pbjn6P1B3GOQ8Y8TeWcTM/P8kiYNWwjnBLNSfxaWT2dUmLo/Csi7wGRPnuXHM7N2+7EQZdJkiyYOLAbtWhQpUY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Zn4mU1FN; 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="Zn4mU1FN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E253C32782; Sun, 26 May 2024 09:43:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1716716581; bh=JgenaFV+7nFpbALnZO+VIAqY0wsCGJI94ujw+zT+hmw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Zn4mU1FN2KZhmYmrggl36XXCvUqXi47EGeKJazGsFmXlofHxTJD0T+YiQw/qAAaO1 EwNFWgfCCbq0Y6fjImyLL+cPa0F2gXOnHsvHu/jTqVdTvrWnNkf9qurRGgJ8iyvVAc DoWssMkxYW2A44aNc8jkgfbaN31GMctF9z20chRcbV9HbnJPlVKtNjbgruqZUzNZ6u 1Ab9xAwnOkMlfY8QO9fewBqWFUknPTO7LYpyZxuJB5jjt4ljkRMtfMnr5v3YEa1377 4vA9tG5ZsHHVcz9TdyJ35XNiCzhVwT5/Kaiaa3y0kxcas7UEskGvCwDn+/9SGHukL8 EpSEWXbdVwt6g== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jens Axboe , Sasha Levin , io-uring@vger.kernel.org Subject: [PATCH AUTOSEL 6.6 06/11] io_uring/sqpoll: work around a potential audit memory leak Date: Sun, 26 May 2024 05:42:44 -0400 Message-ID: <20240526094251.3413178-6-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240526094251.3413178-1-sashal@kernel.org> References: <20240526094251.3413178-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.6.31 Content-Transfer-Encoding: 8bit From: Jens Axboe [ Upstream commit c4ce0ab27646f4206a9eb502d6fe45cb080e1cae ] kmemleak complains that there's a memory leak related to connect handling: unreferenced object 0xffff0001093bdf00 (size 128): comm "iou-sqp-455", pid 457, jiffies 4294894164 hex dump (first 32 bytes): 02 00 fa ea 7f 00 00 01 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 2e481b1a): [<00000000c0a26af4>] kmemleak_alloc+0x30/0x38 [<000000009c30bb45>] kmalloc_trace+0x228/0x358 [<000000009da9d39f>] __audit_sockaddr+0xd0/0x138 [<0000000089a93e34>] move_addr_to_kernel+0x1a0/0x1f8 [<000000000b4e80e6>] io_connect_prep+0x1ec/0x2d4 [<00000000abfbcd99>] io_submit_sqes+0x588/0x1e48 [<00000000e7c25e07>] io_sq_thread+0x8a4/0x10e4 [<00000000d999b491>] ret_from_fork+0x10/0x20 which can can happen if: 1) The command type does something on the prep side that triggers an audit call. 2) The thread hasn't done any operations before this that triggered an audit call inside ->issue(), where we have audit_uring_entry() and audit_uring_exit(). Work around this by issuing a blanket NOP operation before the SQPOLL does anything. Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- io_uring/sqpoll.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/io_uring/sqpoll.c b/io_uring/sqpoll.c index 65b5dbe3c850e..350436e55aafe 100644 --- a/io_uring/sqpoll.c +++ b/io_uring/sqpoll.c @@ -240,6 +240,14 @@ static int io_sq_thread(void *data) sqd->sq_cpu = raw_smp_processor_id(); } + /* + * Force audit context to get setup, in case we do prep side async + * operations that would trigger an audit call before any issue side + * audit has been done. + */ + audit_uring_entry(IORING_OP_NOP); + audit_uring_exit(true, 0); + mutex_lock(&sqd->lock); while (1) { bool cap_entries, sqt_spin = false; -- 2.43.0