From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.19]) (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 7BDDE525D; Fri, 12 Apr 2024 02:03:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.19 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712887422; cv=none; b=kyaIlK5Uu8GMZG4JEhlFQ0JUxKnQzLMqGq8Ldxf2q7b7sq10qMlslsjLSTQf0sq/aKpMFvThGAgDgG6oy/xfkWKrs0Ks22jthwSqsbuQqtK8/l1Kn5CSOA4BalooiPNyfr3Fbs5nZ2rjZ8OlI6lRZfEA4my00rnio8Cq1nvcLuE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712887422; c=relaxed/simple; bh=32I00JzTHxnizPyNO+FSMhrceoVRAWHSz7lsTnztRjg=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=gayD2mp30Eg4I2F7lVxzICFES/UHuTtDCNJJE2AX74DLgDtxHgW5Qwbmj25h8yoDNc4TVVAWoddiRdJT2g8uYcPe1Ah1ZQaLmSuMRGrAWHghnIHRWLQ74vHY9swa/B8+BtryF+Xfl+cnh5DYn+EATM8if3lCc9IEwP/9XqQcV6U= 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=AWPKjqS+; arc=none smtp.client-ip=192.198.163.19 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="AWPKjqS+" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1712887421; x=1744423421; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=32I00JzTHxnizPyNO+FSMhrceoVRAWHSz7lsTnztRjg=; b=AWPKjqS+hoGmwW8TYosCncF9pA6WH99+//iZ7EPqSfi+ylLMdXh8mln/ onVQ7dLHWI51KYXKui5EJjMoAgcQF9lYLY0ejTXDF+sO6PpqtDaK3qhSn sUrw4pC06q0OisjeRgkT+Z2vE32a4MjE/6FXUW+Ffow0kTGEEM0IqhBKA 0l8GT3FMlfXY1eUCO3KOD3ws435MG5oSsVWxF5WV5UGEYBiu5w5sdxR9t TKIPJOmI/werEgAogrq7obeTbSSZYg9jeFj60DMx3fNbq3rzH49AD2R9k kqzmW0KsPGChdE3WgTZ+tngmmxL5eYfLclMG3JSgm6MF8gT/bvHNvEq3B w==; X-CSE-ConnectionGUID: +vN4tx8PQAiAJSgB3asmNQ== X-CSE-MsgGUID: 1FcdDa8oRo6U/k/IOXfGaA== X-IronPort-AV: E=McAfee;i="6600,9927,11041"; a="8191586" X-IronPort-AV: E=Sophos;i="6.07,194,1708416000"; d="scan'208";a="8191586" Received: from orviesa010.jf.intel.com ([10.64.159.150]) by fmvoesa113.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Apr 2024 19:03:40 -0700 X-CSE-ConnectionGUID: 2IfnSC7USKmo2w+IHmccLw== X-CSE-MsgGUID: Tx0EYjaaR6OltRqbP5cKTw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.07,194,1708416000"; d="scan'208";a="21001354" Received: from dev-qz.sh.intel.com (HELO localhost) ([10.239.147.89]) by orviesa010-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Apr 2024 19:03:38 -0700 From: qiang4.zhang@linux.intel.com To: Masami Hiramatsu , Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Qiang Zhang Subject: [PATCH] bootconfig: use memblock_free_late to free xbc memory to buddy Date: Fri, 12 Apr 2024 10:03:26 +0800 Message-Id: <20240412020325.290330-1-qiang4.zhang@linux.intel.com> X-Mailer: git-send-email 2.39.2 Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Qiang Zhang On the time to free xbc memory, memblock has handed over memory to buddy allocator. So it doesn't make sense to free memory back to memblock. memblock_free() called by xbc_exit() even causes UAF bugs on architectures with CONFIG_ARCH_KEEP_MEMBLOCK disabled like x86. Following KASAN logs shows this case. [ 9.410890] ================================================================== [ 9.418962] BUG: KASAN: use-after-free in memblock_isolate_range+0x12d/0x260 [ 9.426850] Read of size 8 at addr ffff88845dd30000 by task swapper/0/1 [ 9.435901] CPU: 9 PID: 1 Comm: swapper/0 Tainted: G U 6.9.0-rc3-00208-g586b5dfb51b9 #5 [ 9.446403] Hardware name: Intel Corporation RPLP LP5 (CPU:RaptorLake)/RPLP LP5 (ID:13), BIOS IRPPN02.01.01.00.00.19.015.D-00000000 Dec 28 2023 [ 9.460789] Call Trace: [ 9.463518] [ 9.465859] dump_stack_lvl+0x53/0x70 [ 9.469949] print_report+0xce/0x610 [ 9.473944] ? __virt_addr_valid+0xf5/0x1b0 [ 9.478619] ? memblock_isolate_range+0x12d/0x260 [ 9.483877] kasan_report+0xc6/0x100 [ 9.487870] ? memblock_isolate_range+0x12d/0x260 [ 9.493125] memblock_isolate_range+0x12d/0x260 [ 9.498187] memblock_phys_free+0xb4/0x160 [ 9.502762] ? __pfx_memblock_phys_free+0x10/0x10 [ 9.508021] ? mutex_unlock+0x7e/0xd0 [ 9.512111] ? __pfx_mutex_unlock+0x10/0x10 [ 9.516786] ? kernel_init_freeable+0x2d4/0x430 [ 9.521850] ? __pfx_kernel_init+0x10/0x10 [ 9.526426] xbc_exit+0x17/0x70 [ 9.529935] kernel_init+0x38/0x1e0 [ 9.533829] ? _raw_spin_unlock_irq+0xd/0x30 [ 9.538601] ret_from_fork+0x2c/0x50 [ 9.542596] ? __pfx_kernel_init+0x10/0x10 [ 9.547170] ret_from_fork_asm+0x1a/0x30 [ 9.551552] [ 9.555649] The buggy address belongs to the physical page: [ 9.561875] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x45dd30 [ 9.570821] flags: 0x200000000000000(node=0|zone=2) [ 9.576271] page_type: 0xffffffff() [ 9.580167] raw: 0200000000000000 ffffea0011774c48 ffffea0012ba1848 0000000000000000 [ 9.588823] raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 [ 9.597476] page dumped because: kasan: bad access detected [ 9.605362] Memory state around the buggy address: [ 9.610714] ffff88845dd2ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 9.618786] ffff88845dd2ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 9.626857] >ffff88845dd30000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 9.634930] ^ [ 9.638534] ffff88845dd30080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 9.646605] ffff88845dd30100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 9.654675] ================================================================== Signed-off-by: Qiang Zhang --- lib/bootconfig.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/bootconfig.c b/lib/bootconfig.c index c59d26068a64..4524ee944df0 100644 --- a/lib/bootconfig.c +++ b/lib/bootconfig.c @@ -63,7 +63,7 @@ static inline void * __init xbc_alloc_mem(size_t size) static inline void __init xbc_free_mem(void *addr, size_t size) { - memblock_free(addr, size); + memblock_free_late(__pa(addr), size); } #else /* !__KERNEL__ */ -- 2.39.2