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 A038F19A29C; Thu, 25 Jul 2024 14:42:16 +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=1721918536; cv=none; b=CGP6BEJ+Jk6lKKLyTQKUE+NQIsk4WMLog0nf8w5LjjPNXOUJvW3GU/6fV/GWk9x5o5dELjATZ0lhlbGln3OIT6lQR1MGALAravdenY9fEAm4zq28bzM0QR1a2wXWW/ULVzFqFpxlaU+ziKa5XSMrmsvOe2QZcx6lcgDN+JNy+6Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721918536; c=relaxed/simple; bh=tSZ/WZSSLko6gD23VUnW6yB1splUNbrv2oygAsp1YxU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JbUL6Fu120PaEJjAy7bItBNt25h8VYkXun33vNXG6CAcoY1SLJSkqWiY9RAFGc7bBUUzuQsylUlLfg6Z+tWatpO+WlqWyn6ljp6pnOz3PN6XqBsIUOJDO9Z1ZibOMVD7i8PvYgyie2OBFWcjghg0DfMQSP75Eb37AMNxFf2LNoo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=R3x/BRCO; 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="R3x/BRCO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2416EC116B1; Thu, 25 Jul 2024 14:42:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1721918536; bh=tSZ/WZSSLko6gD23VUnW6yB1splUNbrv2oygAsp1YxU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=R3x/BRCOwMtH80BJWEK1RZ04wc8AfY+89nTnvopFpYyiOTRj98j6HPO0IHd17QA5g ejrZzYYKZXUcirLIhb0mHBKQfMzUKcZgnNKLZGCCHKEbXqRilGGDtgK6Jqz60ko2i8 LTwi5At8HAb25TXrsWGDYkohdi5JjsyuWx3dIJQI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dmitry Antipov , Johannes Berg , Sasha Levin Subject: [PATCH 5.4 07/43] wifi: mac80211: fix UBSAN noise in ieee80211_prep_hw_scan() Date: Thu, 25 Jul 2024 16:36:30 +0200 Message-ID: <20240725142730.752499162@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240725142730.471190017@linuxfoundation.org> References: <20240725142730.471190017@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: Dmitry Antipov [ Upstream commit 92ecbb3ac6f3fe8ae9edf3226c76aa17b6800699 ] When testing the previous patch with CONFIG_UBSAN_BOUNDS, I've noticed the following: UBSAN: array-index-out-of-bounds in net/mac80211/scan.c:372:4 index 0 is out of range for type 'struct ieee80211_channel *[]' CPU: 0 PID: 1435 Comm: wpa_supplicant Not tainted 6.9.0+ #1 Hardware name: LENOVO 20UN005QRT/20UN005QRT <...BIOS details...> Call Trace: dump_stack_lvl+0x2d/0x90 __ubsan_handle_out_of_bounds+0xe7/0x140 ? timerqueue_add+0x98/0xb0 ieee80211_prep_hw_scan+0x2db/0x480 [mac80211] ? __kmalloc+0xe1/0x470 __ieee80211_start_scan+0x541/0x760 [mac80211] rdev_scan+0x1f/0xe0 [cfg80211] nl80211_trigger_scan+0x9b6/0xae0 [cfg80211] ... Since '__ieee80211_start_scan()' leaves 'hw_scan_req->req.n_channels' uninitialized, actual boundaries of 'hw_scan_req->req.channels' can't be checked in 'ieee80211_prep_hw_scan()'. Although an initialization of 'hw_scan_req->req.n_channels' introduces some confusion around allocated vs. used VLA members, this shouldn't be a problem since everything is correctly adjusted soon in 'ieee80211_prep_hw_scan()'. Cleanup 'kmalloc()' math in '__ieee80211_start_scan()' by using the convenient 'struct_size()' as well. Signed-off-by: Dmitry Antipov Link: https://msgid.link/20240517153332.18271-2-dmantipov@yandex.ru [improve (imho) indentation a bit] Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin --- net/mac80211/scan.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c index ee65f1f50a0ab..d53018610d8a5 100644 --- a/net/mac80211/scan.c +++ b/net/mac80211/scan.c @@ -701,15 +701,21 @@ static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, local->hw_scan_ies_bufsize *= n_bands; } - local->hw_scan_req = kmalloc( - sizeof(*local->hw_scan_req) + - req->n_channels * sizeof(req->channels[0]) + - local->hw_scan_ies_bufsize, GFP_KERNEL); + local->hw_scan_req = kmalloc(struct_size(local->hw_scan_req, + req.channels, + req->n_channels) + + local->hw_scan_ies_bufsize, + GFP_KERNEL); if (!local->hw_scan_req) return -ENOMEM; local->hw_scan_req->req.ssids = req->ssids; local->hw_scan_req->req.n_ssids = req->n_ssids; + /* None of the channels are actually set + * up but let UBSAN know the boundaries. + */ + local->hw_scan_req->req.n_channels = req->n_channels; + ies = (u8 *)local->hw_scan_req + sizeof(*local->hw_scan_req) + req->n_channels * sizeof(req->channels[0]); -- 2.43.0