From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Wed, 23 Nov 2016 14:45:20 +0100 (CET) Received: from mailapp01.imgtec.com ([195.59.15.196]:35526 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S23993008AbcKWNoEzXwXG (ORCPT ); Wed, 23 Nov 2016 14:44:04 +0100 Received: from HHMAIL01.hh.imgtec.org (unknown [10.100.10.19]) by Forcepoint Email with ESMTPS id 9A55063810810; Wed, 23 Nov 2016 13:43:55 +0000 (GMT) Received: from WR-NOWAKOWSKI.kl.imgtec.org (10.80.2.5) by HHMAIL01.hh.imgtec.org (10.100.10.21) with Microsoft SMTP Server (TLS) id 14.3.294.0; Wed, 23 Nov 2016 13:43:58 +0000 From: Marcin Nowakowski To: Ralf Baechle , Subject: [PATCH 03/10] MIPS: init: ensure bootmem does not corrupt reserved memory Date: Wed, 23 Nov 2016 14:43:45 +0100 Message-ID: <1479908632-30392-4-git-send-email-marcin.nowakowski@imgtec.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1479908632-30392-1-git-send-email-marcin.nowakowski@imgtec.com> References: <1479908632-30392-1-git-send-email-marcin.nowakowski@imgtec.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.80.2.5] Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 55874 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: marcin.nowakowski@imgtec.com Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips Current init code initialises bootmem allocator with all of the low memory that it assumes is available, but does not check for reserved memory block, which can lead to corruption of data that may be stored there. Move bootmem's allocation map to a location that does not cross any reserved regions Signed-off-by: Marcin Nowakowski --- arch/mips/kernel/setup.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 71 insertions(+), 3 deletions(-) diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c index 8ebad24..64b38d4 100644 --- a/arch/mips/kernel/setup.c +++ b/arch/mips/kernel/setup.c @@ -153,6 +153,35 @@ void __init detect_memory_region(phys_addr_t start, phys_addr_t sz_min, phys_add add_memory_region(start, size, BOOT_MEM_RAM); } +bool __init memory_region_available(phys_addr_t start, phys_addr_t size) +{ + int i; + bool in_ram = false, free = true; + + for (i = 0; i < boot_mem_map.nr_map; i++) { + phys_addr_t start_, end_; + + start_ = boot_mem_map.map[i].addr; + end_ = boot_mem_map.map[i].addr + boot_mem_map.map[i].size; + + switch (boot_mem_map.map[i].type) { + case BOOT_MEM_RAM: + if (start >= start_ && start + size <= end_) + in_ram = true; + break; + case BOOT_MEM_RESERVED: + if ((start >= start_ && start < end_) || + (start < start_ && start + size >= start_)) + free = false; + break; + default: + continue; + } + } + + return in_ram && free; +} + static void __init print_memory_map(void) { int i; @@ -332,11 +361,19 @@ static void __init bootmem_init(void) #else /* !CONFIG_SGI_IP27 */ +static unsigned long __init bootmap_bytes(unsigned long pages) +{ + unsigned long bytes = DIV_ROUND_UP(pages, 8); + + return ALIGN(bytes, sizeof(long)); +} + static void __init bootmem_init(void) { unsigned long reserved_end; unsigned long mapstart = ~0UL; unsigned long bootmap_size; + bool bootmap_valid = false; int i; /* @@ -430,11 +467,42 @@ static void __init bootmem_init(void) #endif /* - * Initialize the boot-time allocator with low memory only. + * check that mapstart doesn't overlap with any of + * memory regions that have been reserved through eg. DTB */ - bootmap_size = init_bootmem_node(NODE_DATA(0), mapstart, - min_low_pfn, max_low_pfn); + bootmap_size = bootmap_bytes(max_low_pfn - min_low_pfn); + + bootmap_valid = memory_region_available(PFN_PHYS(mapstart), + bootmap_size); + for (i = 0; i < boot_mem_map.nr_map && !bootmap_valid; i++) { + unsigned long mapstart_addr; + + switch (boot_mem_map.map[i].type) { + case BOOT_MEM_RESERVED: + mapstart_addr = PFN_ALIGN(boot_mem_map.map[i].addr + + boot_mem_map.map[i].size); + if (PHYS_PFN(mapstart_addr) < mapstart) + break; + + bootmap_valid = memory_region_available(mapstart_addr, + bootmap_size); + if (bootmap_valid) + mapstart = PHYS_PFN(mapstart_addr); + break; + default: + break; + } + } + if (!bootmap_valid) + panic("No memory area to place a bootmap bitmap"); + + /* + * Initialize the boot-time allocator with low memory only. + */ + if (bootmap_size != init_bootmem_node(NODE_DATA(0), mapstart, + min_low_pfn, max_low_pfn)) + panic("Unexpected memory size required for bootmap"); for (i = 0; i < boot_mem_map.nr_map; i++) { unsigned long start, end; -- 2.7.4 From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailapp01.imgtec.com ([195.59.15.196]:35526 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S23993008AbcKWNoEzXwXG (ORCPT ); Wed, 23 Nov 2016 14:44:04 +0100 From: Marcin Nowakowski Subject: [PATCH 03/10] MIPS: init: ensure bootmem does not corrupt reserved memory Date: Wed, 23 Nov 2016 14:43:45 +0100 Message-ID: <1479908632-30392-4-git-send-email-marcin.nowakowski@imgtec.com> In-Reply-To: <1479908632-30392-1-git-send-email-marcin.nowakowski@imgtec.com> References: <1479908632-30392-1-git-send-email-marcin.nowakowski@imgtec.com> MIME-Version: 1.0 Content-Type: text/plain Return-Path: Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-subscribe: List-owner: List-post: List-archive: To: Ralf Baechle , linux-mips@linux-mips.org Message-ID: <20161123134345.Ofs4id-BZhveHPrrxt3hoGD3mBi16e7oWbFAXAHFy_A@z> Current init code initialises bootmem allocator with all of the low memory that it assumes is available, but does not check for reserved memory block, which can lead to corruption of data that may be stored there. Move bootmem's allocation map to a location that does not cross any reserved regions Signed-off-by: Marcin Nowakowski --- arch/mips/kernel/setup.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 71 insertions(+), 3 deletions(-) diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c index 8ebad24..64b38d4 100644 --- a/arch/mips/kernel/setup.c +++ b/arch/mips/kernel/setup.c @@ -153,6 +153,35 @@ void __init detect_memory_region(phys_addr_t start, phys_addr_t sz_min, phys_add add_memory_region(start, size, BOOT_MEM_RAM); } +bool __init memory_region_available(phys_addr_t start, phys_addr_t size) +{ + int i; + bool in_ram = false, free = true; + + for (i = 0; i < boot_mem_map.nr_map; i++) { + phys_addr_t start_, end_; + + start_ = boot_mem_map.map[i].addr; + end_ = boot_mem_map.map[i].addr + boot_mem_map.map[i].size; + + switch (boot_mem_map.map[i].type) { + case BOOT_MEM_RAM: + if (start >= start_ && start + size <= end_) + in_ram = true; + break; + case BOOT_MEM_RESERVED: + if ((start >= start_ && start < end_) || + (start < start_ && start + size >= start_)) + free = false; + break; + default: + continue; + } + } + + return in_ram && free; +} + static void __init print_memory_map(void) { int i; @@ -332,11 +361,19 @@ static void __init bootmem_init(void) #else /* !CONFIG_SGI_IP27 */ +static unsigned long __init bootmap_bytes(unsigned long pages) +{ + unsigned long bytes = DIV_ROUND_UP(pages, 8); + + return ALIGN(bytes, sizeof(long)); +} + static void __init bootmem_init(void) { unsigned long reserved_end; unsigned long mapstart = ~0UL; unsigned long bootmap_size; + bool bootmap_valid = false; int i; /* @@ -430,11 +467,42 @@ static void __init bootmem_init(void) #endif /* - * Initialize the boot-time allocator with low memory only. + * check that mapstart doesn't overlap with any of + * memory regions that have been reserved through eg. DTB */ - bootmap_size = init_bootmem_node(NODE_DATA(0), mapstart, - min_low_pfn, max_low_pfn); + bootmap_size = bootmap_bytes(max_low_pfn - min_low_pfn); + + bootmap_valid = memory_region_available(PFN_PHYS(mapstart), + bootmap_size); + for (i = 0; i < boot_mem_map.nr_map && !bootmap_valid; i++) { + unsigned long mapstart_addr; + + switch (boot_mem_map.map[i].type) { + case BOOT_MEM_RESERVED: + mapstart_addr = PFN_ALIGN(boot_mem_map.map[i].addr + + boot_mem_map.map[i].size); + if (PHYS_PFN(mapstart_addr) < mapstart) + break; + + bootmap_valid = memory_region_available(mapstart_addr, + bootmap_size); + if (bootmap_valid) + mapstart = PHYS_PFN(mapstart_addr); + break; + default: + break; + } + } + if (!bootmap_valid) + panic("No memory area to place a bootmap bitmap"); + + /* + * Initialize the boot-time allocator with low memory only. + */ + if (bootmap_size != init_bootmem_node(NODE_DATA(0), mapstart, + min_low_pfn, max_low_pfn)) + panic("Unexpected memory size required for bootmap"); for (i = 0; i < boot_mem_map.nr_map; i++) { unsigned long start, end; -- 2.7.4