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 907CD7172B; Sun, 24 Mar 2024 22:35:40 +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=1711319740; cv=none; b=qtjTdWF7+Rzz/LSHkvGSXzPpgy2qpBP6shg6wOfLEtQtaxlevTjy8bYmPPd6hfaXbO+1TYU/+5sSpuRUuZk1rNMp7rbw3d49FU8eRM/PsSpqT6QdH9vH7doCTV6O1f9kYZGbaVLefrzzy/UBsBJo9A5IvIz9e8d+ZVigPGWeRaA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711319740; c=relaxed/simple; bh=+mRypTj2AN+uFrmsMst73xXavbGCXAj069qIzrAjzZE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nqm0uwJ4YiwHDVJOzWiPtmaM4bApbk1tJHN7tzRBWU9ftmBA/mlwEVINIEaV5y5Ulq/wgBgjaP2P4kDcNpPqU/ZAamxsd9IdJy3fjFqKrO3ebtZ0SCmAMt8Qfn08OAFn7T9VhBprokill125pHghTcjY/MRz49gZ1uSG78nKZco= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fuEoHIDY; 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="fuEoHIDY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 66339C43399; Sun, 24 Mar 2024 22:35:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711319740; bh=+mRypTj2AN+uFrmsMst73xXavbGCXAj069qIzrAjzZE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fuEoHIDYd2Et/hDtJ+r072Bm7rwYTo+R/HhliPb+cUeIqtXCx9/iXMkuOhwR0klEL 7Q1OzTI/4SLjKAdEaLTHq075nh94Vr/s3SRPAxPYqkK6ES1Xg/5HKxn2g2juMEzWfM 4+QSH0ZuO+7YI1Vfy3Qc6ePZWtbnws972UKVARKY6gSIoaAh3+yG6IAyGy5K8dzCbe AL++iwPTgn/Me7uMHLNPbRz126NpClBzrOoZEHcibRPSvb99NUJK74bwOavMCZ9D9O ObnAOMRNWpI4cg6QrzhrMtaFySmQ2mlxy5rQZ0GouF7xnHEbRGicG1etF69mcMlmBr C8qDfR8EPiv2A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Dan Carpenter , Jens Axboe , Sasha Levin Subject: [PATCH 6.8 041/715] io_uring/net: fix overflow check in io_recvmsg_mshot_prep() Date: Sun, 24 Mar 2024 18:23:40 -0400 Message-ID: <20240324223455.1342824-42-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240324223455.1342824-1-sashal@kernel.org> References: <20240324223455.1342824-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Dan Carpenter [ Upstream commit 8ede3db5061bb1fe28e2c9683329aafa89d2b1b4 ] The "controllen" variable is type size_t (unsigned long). Casting it to int could lead to an integer underflow. The check_add_overflow() function considers the type of the destination which is type int. If we add two positive values and the result cannot fit in an integer then that's counted as an overflow. However, if we cast "controllen" to an int and it turns negative, then negative values *can* fit into an int type so there is no overflow. Good: 100 + (unsigned long)-4 = 96 <-- overflow Bad: 100 + (int)-4 = 96 <-- no overflow I deleted the cast of the sizeof() as well. That's not a bug but the cast is unnecessary. Fixes: 9b0fc3c054ff ("io_uring: fix types in io_recvmsg_multishot_overflow") Signed-off-by: Dan Carpenter Link: https://lore.kernel.org/r/138bd2e2-ede8-4bcc-aa7b-f3d9de167a37@moroto.mountain Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- io_uring/net.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/io_uring/net.c b/io_uring/net.c index 1d9bfde71809a..058e04ea68c04 100644 --- a/io_uring/net.c +++ b/io_uring/net.c @@ -544,10 +544,10 @@ static int io_recvmsg_mshot_prep(struct io_kiocb *req, if (unlikely(namelen < 0)) return -EOVERFLOW; - if (check_add_overflow((int)sizeof(struct io_uring_recvmsg_out), + if (check_add_overflow(sizeof(struct io_uring_recvmsg_out), namelen, &hdr)) return -EOVERFLOW; - if (check_add_overflow(hdr, (int)controllen, &hdr)) + if (check_add_overflow(hdr, controllen, &hdr)) return -EOVERFLOW; iomsg->namelen = namelen; -- 2.43.0