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 CE2AB19F0F8; Tue, 7 May 2024 23:14:17 +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=1715123657; cv=none; b=Ct9Eovi6s/ph8IwgZv7Dc43ZKb56xUbK5iQnPOaW27JDVmW8teBmQuBkbvH/K4bagqFPY4AhU6WHSGCH9gQRYy+D5FkEXSjugMvjDSmvqeuOOT98u+/s7mlXHOBs8Bc47Bb4zhS+JDKY+URU8mLdtCce8KEemOQ6FmMeQsmPHMM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715123657; c=relaxed/simple; bh=039aMml/7RrxBQVlYP2HFi9FN5TCDhwn8OIvAOg4d+g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rPrFjY7AZ1uMi+OZ4aUCasENQVgeEgvTAI5x6YzBWUMp+BIyOasirAN33ys6/z9EXDnQOls6Zs8lShPcnS2wjAOKdIMIBDzqWrDiSImmAMjuMCjVPimjbOGWbiZ9JWFZInQg3vYFuOylCj75tAlcYz00W1tvmwCfJQORgR/krps= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=lquJQisr; 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="lquJQisr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C438C4AF17; Tue, 7 May 2024 23:14:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1715123657; bh=039aMml/7RrxBQVlYP2HFi9FN5TCDhwn8OIvAOg4d+g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lquJQisrYhX32kspyr/UrEMBf0RfP9KYuWGFR6eC02ompZ39tP35H9Sp59SMnSEYx M3oVu6FlIzPk7wjwR2dzFcmxxwLTW9Q6Bu5AiQGfa6qYUExsn+TjHow7Pl4NYm87hL d8UfYS2Rd3kHhPueC7mYac5lD+hC5xpMHt2GpCX5cq32KHIyT4STasEA1B/gamWuKA qta7EydMROVoKBCDKM4d+U70d6lFFWYxwV8klvZwtSAZ5fUui771UU0fKFjP8D24XM jfdP0Rzy+4MtzGCeiaLRCT2i3mubh1/oznY4aMKnfpOi3McTNRUScMoa+ovsk9rHKv w8QwxT09ht6MA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Thanassis Avgerinos , Takashi Sakamoto , Sasha Levin , linux1394-devel@lists.sourceforge.net Subject: [PATCH AUTOSEL 5.10 6/9] firewire: nosy: ensure user_length is taken into account when fetching packet contents Date: Tue, 7 May 2024 19:14:01 -0400 Message-ID: <20240507231406.395123-6-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240507231406.395123-1-sashal@kernel.org> References: <20240507231406.395123-1-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 X-stable-base: Linux 5.10.216 Content-Transfer-Encoding: 8bit From: Thanassis Avgerinos [ Upstream commit 38762a0763c10c24a4915feee722d7aa6e73eb98 ] Ensure that packet_buffer_get respects the user_length provided. If the length of the head packet exceeds the user_length, packet_buffer_get will now return 0 to signify to the user that no data were read and a larger buffer size is required. Helps prevent user space overflows. Signed-off-by: Thanassis Avgerinos Signed-off-by: Takashi Sakamoto Signed-off-by: Sasha Levin --- drivers/firewire/nosy.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/firewire/nosy.c b/drivers/firewire/nosy.c index 88ed971e32c0d..42d9f25efc5c3 100644 --- a/drivers/firewire/nosy.c +++ b/drivers/firewire/nosy.c @@ -148,10 +148,12 @@ packet_buffer_get(struct client *client, char __user *data, size_t user_length) if (atomic_read(&buffer->size) == 0) return -ENODEV; - /* FIXME: Check length <= user_length. */ + length = buffer->head->length; + + if (length > user_length) + return 0; end = buffer->data + buffer->capacity; - length = buffer->head->length; if (&buffer->head->data[length] < end) { if (copy_to_user(data, buffer->head->data, length)) -- 2.43.0