From patchwork Wed Oct 9 06:07:01 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mika Westerberg X-Patchwork-Id: 834561 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.18]) (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 C3FE155E53 for ; Wed, 9 Oct 2024 06:07:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.18 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728454026; cv=none; b=Ml96UMocv+s7rPtgtYAnLAr7tzzHU4sWHxdgs5iyOdLCwmIp3t607JS4wAPV03QJ+mgQSFcORGoWgp++CGo5PMZrC96qIPjEh86Nx9oZ4os+yHVxay5C6ca3/VFT8QCs6xAuchN4RL09QF7TH3hlWvj2kVv/lDDkprmX8oV9XQg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728454026; c=relaxed/simple; bh=S3EQeQXk+FUsyOXT0Yozyd0+LsMe/i+q2U0bQTgYnSE=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=mObWX7NZ1VV+Vi+uzRSOYVh7pxhqDVO0AJqeaa754t/soPYeyYm/iT1/ICiEUxNYdm7+bnywNjhKc0A2T2SO9NVaAZRgIwFjnm3DrHBzNyIXR/8iplQxD7+CsqRPyTAGPS3TiibOuis/0D3RNVsswMezJuXii7F7RkGuiBt+w1A= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=eJfJC+80; arc=none smtp.client-ip=192.198.163.18 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="eJfJC+80" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1728454025; x=1759990025; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=S3EQeQXk+FUsyOXT0Yozyd0+LsMe/i+q2U0bQTgYnSE=; b=eJfJC+80ZNzzlzZQvGoMbQRxIWa/A4yNuA71YoTxekdPbuaFpgkjErzP wmc238jS0zPUAvQ5GnPfO9c/zK+KIcvvwqkQPUpLt4fC0KIeP4XO4ZWSe LgcsxQLWs0eLj1bxGdHHtLhn3SwIQNinsiYA+qgRDM43iLatXX35Zcm70 1ICGBhYJORqm5az3xE6NBrN0cNDdhcrEpCGKBYF7trmmhsbhI8yhpKrRP YMvR3hN/etsNVMbNfKevO6d+t4aXyRst2lcepCqJ3HdkWEdPbwW8u+B+W OG4bwZVhjPUbmgcUTNLC8Fo0Nmt09wkhWHpzH9/eUqaXRmPGhgvRwShpu g==; X-CSE-ConnectionGUID: VLcL691iSBOfC/vPeIAB5g== X-CSE-MsgGUID: WHrSYHPUR7mtuhnImVMcBQ== X-IronPort-AV: E=McAfee;i="6700,10204,11219"; a="27180515" X-IronPort-AV: E=Sophos;i="6.11,189,1725346800"; d="scan'208";a="27180515" Received: from fmviesa003.fm.intel.com ([10.60.135.143]) by fmvoesa112.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Oct 2024 23:07:04 -0700 X-CSE-ConnectionGUID: ZSX3rAduQX2CC8/JHoLskw== X-CSE-MsgGUID: Ex3sKHDkQOSecIds1c5Q1A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.11,189,1725346800"; d="scan'208";a="80116841" Received: from black.fi.intel.com ([10.237.72.28]) by fmviesa003.fm.intel.com with ESMTP; 08 Oct 2024 23:07:02 -0700 Received: by black.fi.intel.com (Postfix, from userid 1001) id 7B06D4E2; Wed, 09 Oct 2024 09:07:01 +0300 (EEST) From: Mika Westerberg To: Yehezkel Bernat , Michael Jamet , Lukas Wunner , Andreas Noever Cc: linux-usb@vger.kernel.org, Mika Westerberg Subject: [PATCH] thunderbolt: Fix KASAN reported stack out-of-bounds read in tb_retimer_scan() Date: Wed, 9 Oct 2024 09:07:01 +0300 Message-ID: <20241009060701.2434897-1-mika.westerberg@linux.intel.com> X-Mailer: git-send-email 2.45.2 Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 KASAN reported following issue: BUG: KASAN: stack-out-of-bounds in tb_retimer_scan+0xffe/0x1550 [thunderbolt] Read of size 4 at addr ffff88810111fc1c by task kworker/u56:0/11 CPU: 0 UID: 0 PID: 11 Comm: kworker/u56:0 Tainted: G U 6.11.0+ #1387 Tainted: [U]=USER Workqueue: thunderbolt0 tb_handle_hotplug [thunderbolt] Call Trace: dump_stack_lvl+0x6c/0x90 print_report+0xd1/0x630 kasan_report+0xdb/0x110 __asan_report_load4_noabort+0x14/0x20 tb_retimer_scan+0xffe/0x1550 [thunderbolt] tb_scan_port+0xa6f/0x2060 [thunderbolt] tb_handle_hotplug+0x17b1/0x3080 [thunderbolt] process_one_work+0x626/0x1100 worker_thread+0x6c8/0xfa0 kthread+0x2c8/0x3a0 ret_from_fork+0x3a/0x80 ret_from_fork_asm+0x1a/0x30 This happens because the loop variable still gets incremented by one so max becomes 3 instead of 2, and this makes the second loop read past the the array declared on the stack. Fix this by assigning to max directly in the loop body. Fixes: ff6ab055e070 ("thunderbolt: Add receiver lane margining support for retimers") CC: stable@vger.kernel.org Signed-off-by: Mika Westerberg --- drivers/thunderbolt/retimer.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/thunderbolt/retimer.c b/drivers/thunderbolt/retimer.c index 721319329afa..7db9869a9f3f 100644 --- a/drivers/thunderbolt/retimer.c +++ b/drivers/thunderbolt/retimer.c @@ -516,7 +516,7 @@ int tb_retimer_scan(struct tb_port *port, bool add) */ tb_retimer_set_inbound_sbtx(port); - for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++) { + for (max = 1, i = 1; i <= TB_MAX_RETIMER_INDEX; i++) { /* * Last retimer is true only for the last on-board * retimer (the one connected directly to the Type-C @@ -527,9 +527,10 @@ int tb_retimer_scan(struct tb_port *port, bool add) last_idx = i; else if (ret < 0) break; + + max = i; } - max = i; ret = 0; /* Add retimers if they do not exist already */